module: ietf-l2svc
          
module: ietf-l2vpn-svc
+--rw l2vpn-svc
   +--rw customer-info
   |  +--rw customer-info* [customer-account-number customer-name]
   |     +--rw customer-account-number          uint32
   |     +--rw customer-name                    string
   |     +--rw customer-operation-center
   |        +--rw customer-noc-street-address?  string
   |        +--rw customer-noc-phone-number
   |           +--rw main-phone-num?            uint32
   |           +--rw extension-options?         uint32
   +--rw vpn-services
   |  +--rw vpn-svc* [svc-id]
   |     +--rw svc-id                           string
   |     +--rw svc-type
   |     |  +--rw evc
   |     |  |  +--rw evc-id?   boolean
   |     |  |  +--rw max-number-of-pe?          uint32
   |     |  |  +--rw max-number-of-site?        uint32
   |     |  +--rw ovc
   |     |     +--rw on-net-ovc-id?    boolean
   |     |     +--rw off-net-ov-id?    boolean
   |     +--rw ethernet-svc-type
   |     |  +--rw (ethernet-svc-type)?
   |     |     +--:(e-line)
   |     |     |  +--rw epl?           boolean
   |     |     |  +--rw evpl?          boolean
   |     |     +--:(e-lan)
   |     |     |  +--rw ep-lan?        boolean
   |     |     |  +--rw evp-lan?       boolean
   |     |     +--:(e-access)
   |     |        +--rw access-epl?    boolean
   |     |        +--rw access-evpl?   boolean
   |     +--rw metro-network-id
   |     |  +--rw inter-mkt-service?   boolean
   |     |  +--rw intra-mkt* [metro-mkt-id mkt-name]
   |     |     +--rw metro-mkt-id      uint32
   |     |     +--rw mkt-name          string
   |     +--rw signaling-option
   |     |  +--rw signaling-option* [name type]
   |     |     +--rw name                       string
   |     |     +--rw type                       identityref
   |     |     +--rw mp-bgp-l2vpn
   |     |     |  +--rw vpn-id?        string
   |     |     |  +--rw type?          identityref
   |     |     +--rw mp-bgp-evpn
   |     |     |  +--rw vpn-id?        string
   |     |     |  +--rw type?          identityref
   |     |     +--rw t-ldp-pwe
   |     |     |  +--rw PE-EG-list* [service-ip-lo-addr vc-id]
   |     |     |     +--rw service-ip-lo-addr   inet:ip-address
   |     |     |     +--rw vc-id                string
   |     |     +--rw pwe-encapsulation-type
   |     |     |  +--rw ethernet?      boolean
   |     |     |  +--rw vlan?          boolean
   |     |     +--rw pwe-mtu
   |     |     |  +--rw allow-mtu-mismatch?     boolean
   |     |     +--rw control-word
   |     +--rw load-balance-options
   |     |  +--rw fat-pw?              boolean
   |     |  +--rw entropy-label?       boolean
   |     +--rw svlan-id-ethernet-tag?  string
   |     +--rw cvlan-id-to-evc-map?    string
   |     +--rw service-level-mac-limit?         string
   |     +--rw service-protection
   |        +--rw protection-model
   |        +--rw peer-evc-id
   +--rw site
      +--rw uni-sites
      |  +--rw uni-site* [site-id]
      |     +--rw site-id                       string
      |     +--rw management
      |     |  +--rw site-name?                 string
      |     |  +--rw address?                   inet:ip-address
      |     |  +--rw ce-device-info?            string
      |     |  +--rw type?                      identityref
      |     |  +--rw management-transport?      identityref
      |     +--rw location
      |     |  +--rw address?          string
      |     |  +--rw zip-code?         string
      |     |  +--rw state?            string
      |     |  +--rw city?             string
      |     |  +--rw country-code?     string
      |     +--rw site-diversity {site-diversity}?
      |     |  +--rw groups
      |     |     +--rw group* [group-id]
      |     |        +--rw group-id    string
      |     +--rw security
      |     +--rw signaling-option {signaling-option}?
      |     |  +--rw signaling-option* [name type]
      |     |     +--rw name                    string
      |     |     +--rw type                    identityref
      |     |     +--rw mp-bgp-l2vpn
      |     |     |  +--rw vpn-id?     string
      |     |     |  +--rw type?       identityref
      |     |     +--rw mp-bgp-evpn
      |     |     |  +--rw vpn-id?     string
      |     |     |  +--rw type?       identityref
      |     |     +--rw t-ldp-pwe
      |     |     |  +--rw PE-EG-list* [service-ip-lo-addr vc-id]
      |     |     |     +--rw service-ip-lo-addr     inet:ip-address
      |     |     |     +--rw vc-id                  string
      |     |     +--rw pwe-encapsulation-type
      |     |     |  +--rw ethernet?   boolean
      |     |     |  +--rw vlan?       boolean
      |     |     +--rw pwe-mtu
      |     |     |  +--rw allow-mtu-mismatch?       boolean
      |     |     +--rw control-word
      |     +--rw load-balance-options
      |     |  +--rw fat-pw?              boolean
      |     |  +--rw entropy-label?       boolean
      |     |  +--rw vxlan-source-port?   string
      |     +--rw uni-ports
      |        +--rw uni-port* [uni-id]
      |           +--rw uni-id                       string
      |           +--rw groups
      |           |  +--rw fate-sharing-group-size?  uint16
      |           |  +--rw group* [group-id]
      |           |     +--rw group-id               string
      |           +--rw bearer
      |           |  +--rw phy-interface
      |           |  |  +--rw port-number?           uint32
      |           |  |  +--rw port-speed?            uint32
      |           |  |  +--rw auto-neg?              string
      |           |  |  +--rw phy-mtu?               uint32
      |           |  |  +--rw flow-control?          string
      |           |  |  +--rw encapsulation-type?    enumeration
      |           |  |  +--rw ethertype?             string
      |           |  |  +--rw lldp?                  boolean
      |           |  |  +--rw oam-802.3AH-link {oam-3ah}?
      |           |  |  |  +--rw enable?             boolean
      |           |  |  +--rw uni-loop-prevention?   boolean
      |           |  +--rw LAG-interface
      |           |  |  +--rw LAG-interface* [LAG-interface-number]
      |           |  |     +--rw LAG-interface-number     uint32
      |           |  |     +--rw LACP
      |           |  |        +--rw LACP-state?          identityref
      |           |  |        +--rw LACP-mode?           identityref
      |           |  |        +--rw LACP-speed?          identityref
      |           |  |        +--rw mini-link?           uint32
      |           |  |        +--rw system-priority?     uint16
      |           |  |        +--rw Micro-BFD {Micro-BFD}?
      |           |  |        |  +--rw Micro-BFD-on-off? enumeration
      |           |  |        |  +--rw bfd-interval?     uint32
      |           |  |        |  +--rw bfd-hold-timer?   uint32
      |           |  |        +--rw bfd {bfd}?
      |           |  |        |  +--rw bfd-enabled?      boolean
      |           |  |        |  +--rw (holdtime)?
      |           |  |        |     +--:(profile)
      |           |  |        |     |  +--rw profile-name?   string
      |           |  |        |     +--:(fixed)
      |           |  |        |        +--rw fixed-value?    uint32
      |           |  |        +--rw Member-link-list
      |           |  |        |  +--rw member-link* [name]
      |           |  |        |     +--rw name           string
      |           |  |        |     +--rw port-speed?    uint32
      |           |  |        |     +--rw auto-neg?      string
      |           |  |        |     +--rw mtu?           uint32
      |           |  |        |     +--rw oam-802.3AH-link {oam-3ah}?
      |           |  |        |        +--rw enable?     boolean
      |           |  |        +--rw flow-control?        string
      |           |  |        +--rw encapsulation-type?  enumeration
      |           |  |        +--rw ethertype?           string
      |           |  |        +--rw lldp?                boolean
      |           |  +--rw interface-description?        string
      |           |  +--rw sub-if-id?                    uint32
      |           +--rw ethernet-connection
      |           |  +--rw vlan
      |           |     +--rw svlan-id-ethernet-tag?     string
      |           +--rw evc-mtu?                uint32
      |           +--rw mac-addr-limit
      |           |  +--rw exceeding-option?    uint32
      |           +--rw S-vlan
      |           |  +--rw c-vlan2evc-mapping?  string
      |           +--rw multihoming
      |           |  +--rw multihoming* [ESI]
      |           |     +--rw ESI               string
      |           |     +--rw (redundancy-mode)?
      |           |        +--:(single-active)
      |           |        |  +--rw single-active?   boolean
      |           |        +--:(all-active)
      |           |           +--rw all-active?      boolean
      |           +--rw L2CP-control
      |           |  +--rw stp-rstp-mstp?            control-mode
      |           |  +--rw pause?                    control-mode
      |           |  +--rw lacp-lamp?                control-mode
      |           |  +--rw link-oam?                 control-mode
      |           |  +--rw esmc?                     control-mode
      |           |  +--rw l2cp-802.1x?              control-mode
      |           |  +--rw e-lmi?                    control-mode
      |           |  +--rw lldp?                     boolean
      |           |  +--rw ptp-peer-delay?           control-mode
      |           |  +--rw garp-mrp?                 control-mode
      |           |  +--rw provider-bridge-group?   yang:mac-address
      |           |  +--rw provider-bridge-mvrp?    yang:mac-address
      |           +--rw service
      |           |  +--rw svlan-id-ethernet-tag?    string
      |           |  +--rw cvlan-id-to-evc-map?       string
      |           |  +--rw service-level-mac-limit?  string
      |           |  +--rw service-level
      |           |     +--rw cos-identifier?            identityref
      |           |     +--rw color-identifier?          identityref
      |           |     +--rw ingress-bw-profile-per-evc?    string
      |           |     +--rw ingress-bw-profile-per-cos-id? string
      |           |     +--rw egress-bw-profile-per-evc?     string
      |           |     +--rw egress-bw-profile-per-cos-id?  string
      |           |     +--rw byte-offset?               uint16
      |           |     +--rw policing?                  identityref
      |           |     +--rw performance-tier-option?   identityref
      |           |     +--rw COS?                       uint32
      |           +--rw B-U-M-strom-control
      |           |  +--rw BUM-overall-rate?  uint32
      |           |  +--rw BUM-rate-per-type* [type]
      |           |     +--rw type            identityref
      |           |     +--rw rate?           uint32
      |           +--rw mac-loop-prevention
      |           |  +--rw frequency?         uint32
      |           |  +--rw protection-type?   identityref
      |           |  +--rw number-retries?    uint32
      |           +--rw Ethernet-Service-OAM
      |           |  +--rw MD-name?           string
      |           |  +--rw MD-level?          uint8
      |           |  +--rw cfm-802.1-ag
      |           |  |  +--rw n2-uni-c* [MAID]
      |           |  |  |  +--rw MAID                    string
      |           |  |  |  +--rw mep-id?                 uint32
      |           |  |  |  +--rw mep-level?              uint32
      |           |  |  |  +--rw mep-up-down?            enumeration
      |           |  |  |  +--rw remote-mep-id?          uint32
      |           |  |  |  +--rw cos-for-cfm-pdus?       uint32
      |           |  |  |  +--rw ccm-interval?           uint32
      |           |  |  |  +--rw ccm-holdtime?           uint32
      |           |  |  |  +--rw alarm-priority-defect?  identityref
      |           |  |  |  +--rw ccm-p-bits-pri?   ccm-priority-type
      |           |  |  +--rw n2-uni-n* [MAID]
      |           |  |     +--rw MAID                    string
      |           |  |     +--rw mep-id?                 uint32
      |           |  |     +--rw mep-level?              uint32
      |           |  |     +--rw mep-up-down?            enumeration
      |           |  |     +--rw remote-mep-id?          uint32
      |           |  |     +--rw cos-for-cfm-pdus?       uint32
      |           |  |     +--rw ccm-interval?           uint32
      |           |  |     +--rw ccm-holdtime?           uint32
      |           |  |     +--rw alarm-priority-defect?  identityref
      |           |  |     +--rw ccm-p-bits-pri?   ccm-priority-type
      |           |  +--rw y-1731* [MAID]
      |           |     +--rw MAID                       string
      |           |     +--rw mep-id?                    uint32
      |           |     +--rw type?                      identityref
      |           |     +--rw remote-mep-id?             uint32
      |           |     +--rw message-period?            uint32
      |           |     +--rw measurement-interval?      uint32
      |           |     +--rw cos?                       uint32
      |           |     +--rw loss-measurement?          boolean
      |           |     +--rw synthethic-loss-measurement?  boolean
      |           |     +--rw delay-measurement
      |           |     |  +--rw enable-dm?              boolean
      |           |     |  +--rw two-way?                boolean
      |           |     +--rw frame-size?                uint32
      |           |     +--rw session-type?              enumeration
      |           +--rw security
      +--rw enni-sites
         +--rw enni-site* [site-id]
            +--rw site-id            string
            +--rw location
            |  +--rw address?        string
            |  +--rw zip-code?       string
            |  +--rw state?          string
            |  +--rw city?           string
            |  +--rw country-code?   string
            +--rw site-diversity {site-diversity}?
            |  +--rw groups
            |     +--rw group* [group-id]
            |        +--rw group-id  string
            +--rw management
            |  +--rw site-name?                  string
            |  +--rw address?                    inet:ip-address
            |  +--rw Edge-Gateway-Device-Info?   string
            |  +--rw type?                       identityref
            |  +--rw management-transport?       identityref
            +--rw security
            +--rw service-protection
            |  +--rw protection-model
            |  +--rw peer-evc-id
            +--rw signaling-option {signaling-option}?
            |  +--rw signaling-option* [name type]
            |     +--rw name                     string
            |     +--rw type                     identityref
            |     +--rw mp-bgp-l2vpn
            |     |  +--rw vpn-id?   string
            |     |  +--rw type?     identityref
            |     +--rw mp-bgp-evpn
            |     |  +--rw vpn-id?   string
            |     |  +--rw type?     identityref
            |     +--rw t-ldp-pwe
            |     |  +--rw PE-EG-list* [service-ip-lo-addr vc-id]
            |     |     +--rw service-ip-lo-addr    inet:ip-address
            |     |     +--rw vc-id                 string
            |     +--rw pwe-encapsulation-type
            |     |  +--rw ethernet? boolean
            |     |  +--rw vlan?     boolean
            |     +--rw pwe-mtu
            |     |  +--rw allow-mtu-mismatch?   boolean
            |     +--rw control-word
            +--rw load-balance-options
            |  +--rw fat-pw?              boolean
            |  +--rw entropy-label?       boolean
            |  +--rw vxlan-source-port?   string
            +--rw enni-ports
               +--rw enni-port* [enni-id]
                  +--rw enni-id                  string
                  +--rw remote-carrier-name?     string
                  +--rw bearer
                  |  +--rw phy-interface
                  |  |  +--rw port-number?           uint32
                  |  |  +--rw port-speed?            uint32
                  |  |  +--rw auto-neg?              string
                  |  |  +--rw phy-mtu?               uint32
                  |  |  +--rw flow-control?          string
                  |  |  +--rw encapsulation-type?    enumeration
                  |  |  +--rw ethertype?             string
                  |  |  +--rw lldp?                  boolean
                  |  |  +--rw oam-802.3AH-link {oam-3ah}?
                  |  |  |  +--rw enable?             boolean
                  |  |  +--rw uni-loop-prevention?   boolean
                  |  +--rw LAG-interface
                  |  |  +--rw LAG-interface* [LAG-interface-number]
                  |  |     +--rw LAG-interface-number    uint32
                  |  |     +--rw LACP
                  |  |        +--rw LACP-state?           identityref
                  |  |        +--rw LACP-mode?            identityref
                  |  |        +--rw LACP-speed?           identityref
                  |  |        +--rw mini-link?            uint32
                  |  |        +--rw system-priority?      uint16
                  |  |        +--rw Micro-BFD {Micro-BFD}?
                  |  |        |  +--rw Micro-BFD-on-off?  enumeration
                  |  |        |  +--rw bfd-interval?      uint32
                  |  |        |  +--rw bfd-hold-timer?    uint32
                  |  |        +--rw bfd {bfd}?
                  |  |        |  +--rw bfd-enabled?       boolean
                  |  |        |  +--rw (holdtime)?
                  |  |        |     +--:(profile)
                  |  |        |     |  +--rw profile-name?   string
                  |  |        |     +--:(fixed)
                  |  |        |        +--rw fixed-value?    uint32
                  |  |        +--rw Member-link-list
                  |  |        |  +--rw member-link* [name]
                  |  |        |     +--rw name            string
                  |  |        |     +--rw port-speed?     uint32
                  |  |        |     +--rw auto-neg?       string
                  |  |        |     +--rw mtu?            uint32
                  |  |        |     +--rw oam-802.3AH-link {oam-3ah}?
                  |  |        |        +--rw enable?      boolean
                  |  |        +--rw flow-control?         string
                  |  |        +--rw encapsulation-type?   enumeration
                  |  |        +--rw ethertype?            string
                  |  |        +--rw lldp?                 boolean
                  |  +--rw interface-description?         string
                  |  +--rw sub-if-id?                     uint32
                  +--rw ethernet-connection
                  |  +--rw vlan
                  |     +--rw svlan-id-ethernet-tag?   string
                  +--rw evc-mtu?                 uint32
                  +--rw mac-addr-limit
                  |  +--rw exceeding-option?     uint32
                  +--rw S-vlan
                  |  +--rw c-vlan2evc-mapping?   string
                  +--rw multihoming
                  |  +--rw multihoming* [ESI]
                  |     +--rw ESI                string
                  |     +--rw (redundancy-mode)?
                  |        +--:(single-active)
                  |        |  +--rw single-active?  boolean
                  |        +--:(all-active)
                  |           +--rw all-active?     boolean
                  +--rw L2CP-control
                  |  +--rw stp-rstp-mstp?           control-mode
                  |  +--rw pause?                   control-mode
                  |  +--rw lacp-lamp?               control-mode
                  |  +--rw link-oam?                control-mode
                  |  +--rw esmc?                    control-mode
                  |  +--rw l2cp-802.1x?             control-mode
                  |  +--rw e-lmi?                   control-mode
                  |  +--rw lldp?                    boolean
                  |  +--rw ptp-peer-delay?          control-mode
                  |  +--rw garp-mrp?                control-mode
                  |  +--rw provider-bridge-group?   yang:mac-address
                  |  +--rw provider-bridge-mvrp?    yang:mac-address
                  +--rw service
                  |  +--rw svlan-id-ethernet-tag?     string
                  |  +--rw cvlan-id-to-evc-map?       string
                  |  +--rw service-level-mac-limit?   string
                  |  +--rw service-level
                  |     +--rw cos-identifier?            identityref
                  |     +--rw color-identifier?          identityref
                  |     +--rw ingress-bw-profile-per-evc?    string
                  |     +--rw ingress-bw-profile-per-cos-id? string
                  |     +--rw egress-bw-profile-per-evc?     string
                  |     +--rw egress-bw-profile-per-cos-id?  string
                  |     +--rw byte-offset?               uint16
                  |     +--rw policing?                  identityref
                  |     +--rw performance-tier-option?   identityref
                  |     +--rw COS?                       uint32
                  +--rw B-U-M-strom-control
                  |  +--rw BUM-overall-rate?  uint32
                  |  +--rw BUM-rate-per-type* [type]
                  |     +--rw type            identityref
                  |     +--rw rate?           uint32
                  +--rw mac-loop-prevention
                  |  +--rw frequency?         uint32
                  |  +--rw protection-type?   identityref
                  |  +--rw number-retries?    uint32
                  +--rw Ethernet-Service-OAM
                  |  +--rw MD-name?           string
                  |  +--rw MD-level?          uint8
                  |  +--rw cfm-802.1-ag
                  |  |  +--rw n2-uni-c* [MAID]
                  |  |  |  +--rw MAID                    string
                  |  |  |  +--rw mep-id?                 uint32
                  |  |  |  +--rw mep-level?              uint32
                  |  |  |  +--rw mep-up-down?            enumeration
                  |  |  |  +--rw remote-mep-id?          uint32
                  |  |  |  +--rw cos-for-cfm-pdus?       uint32
                  |  |  |  +--rw ccm-interval?           uint32
                  |  |  |  +--rw ccm-holdtime?           uint32
                  |  |  |  +--rw alarm-priority-defect?  identityref
                  |  |  |  +--rw ccm-p-bits-pri?  ccm-priority-type
                  |  |  +--rw n2-uni-n* [MAID]
                  |  |     +--rw MAID                    string
                  |  |     +--rw mep-id?                 uint32
                  |  |     +--rw mep-level?              uint32
                  |  |     +--rw mep-up-down?            enumeration
                  |  |     +--rw remote-mep-id?          uint32
                  |  |     +--rw cos-for-cfm-pdus?       uint32
                  |  |     +--rw ccm-interval?           uint32
                  |  |     +--rw ccm-holdtime?           uint32
                  |  |     +--rw alarm-priority-defect?  identityref
                  |  |     +--rw ccm-p-bits-pri?  ccm-priority-type
                  |  +--rw y-1731* [MAID]
                  |     +--rw MAID                       string
                  |     +--rw mep-id?                    uint32
                  |     +--rw type?                      identityref
                  |     +--rw remote-mep-id?             uint32
                  |     +--rw message-period?            uint32
                  |     +--rw measurement-interval?      uint32
                  |     +--rw cos?                       uint32
                  |     +--rw loss-measurement?          boolean
                  |     +--rw synthethic-loss-measurement?   boolean
                  |     +--rw delay-measurement
                  |     |  +--rw enable-dm?              boolean
                  |     |  +--rw two-way?                boolean
                  |     +--rw frame-size?                uint32
                  |     +--rw session-type?              enumeration
                  +--rw security
           
         

Figure 6

5.1. Overview of Main Components of the Model

The L2SM model is structured in a way that allows the provider to list multiple circuits of various service types for the same subscriber.

5.1.1. Customer Information

The "customer-info" container contains essential information to identify the subscriber.

"customer-account-number" is an internal alphanumerical number assigned by the service provider to identify the subscriber. It MUST be unique within the service provider?s OSS/BSS system. The actual format depends on the system tool the provider uses. "customer-name" is in more readable form.

Subscriber operation center and main contact number are also listed here for reference purpose.

5.1.2. VPN Service Overview

The "svc-type" container contains two optional leaves: one for EVC (Ethernet Virtual Connection) and the other one for OVC (Operator Virtual Connection). These two parameters are not mutually exclusive. Depending on the service-type, a Layer 2 VPN service may be identified by EVC-ID, OVC-ID, or both.

E-Line and E-LAN provider shall have EVC-ID assigned to the UNI-to-UNI circuit. If the service has remote UNIs in off-net partner's network, there will be one OVC-ID for the on-net segment between local UNI to the E-NNI interconnect, and one OVC-ID for each off-net segment from E-NNI to the remote UNI. E-Access, on the other hand, is OVC-based service. The E-Access service provider will assign OVC-ID for the circuit between UNI to E-NNI.

The "svc-type" container can be augmented in the future to support other new technologies. Note that the "svc-id" should be corresponding to the "svc-type".

5.1.2.1. Service Type

The "svc-type" container contains two cases, one for EVC (Ethernet Virtual Connection), the other for OVC (Operator Virtual Connection). It can be used to indicate the type of service pipe type. The model user also can augment the "svc-type" container with other cases to support future technologies. Notes that the "svc-id" should be corresponding to the "svc-type".

5.1.2.1.1. EVC

The "evc"case contains an "evc-id" leaf with boolean type. The "evc-id" leaf will be marked TRUE for E-Line and E-LAN service types. And the "svc-id" will be associated with the "evc-id". Only one "evc-id" is allowed for each "svc-id".

The EVC ID is intended to be a structured string. Each service provider can decide the nomenclature in its network. For example, many carriers in North American have implemented the COMMON LANGUAGE? Special Service Circuit Codes (CLCI S/S Codes) - Serial Number Format, which is defined in defined in ANSI ATIS-0300097.

5.1.2.1.2. OVC

The "ovc" case contains two boolean subcases: "on-net-ovc" and "off-net-ovc".

For E-Access or services with off-net UNIs, the "on-net-ovc" leaf MUST be marked TRUE. And the "on-net-ovc-id" will be specified.

In case of E-Access, the "svc-id" will be associated with the "on-net-ovc-id". Only one "on-net-ovc-id" is allowed for each "svc-id".

If the service is E-Line or E-LAN with remote UNIs, there will be one, and only one, "on-net-ovc-id" and a list of "off-net-ovc-id"s for the remote UNIs. However, the "svc-id" is still associated with the "evc-id". Only one "evc-id" is allowed for each "svc-id". New ovc type could be added by augmentation.

5.1.2.2. ethernet-svc-type

The "ethernet-svc-type" group contains all supported Ethernet service types. One, and only one, "ethernet-svc-type" must be selected for each "svc-id".

The current supported Ethernet service types are listed in Section 3.2. New service types can be added in the future.

5.1.2.3. Metro Network Partition

Some service providers may divide their network into multiple administrative domains. And a Layer 2 VPN service may span across more than one metro network of the same service provider. The optional "metro-network-id" container is intended be used by these multi-domain providers to differentiate intra-market versus inter-market services.

When the "inter-mkt-service" leaf is marked TRUE, multiple associated "metro-mkt-id"s will be listed. Otherwise, the service is intra-domain and only one "metro-mkt-id" is allowed.

5.1.2.4. vpn-signaling-option

The "signaling-option" container captures service-wide attributes of the L2VPN instance.

Although topology discovery or network device configurations is purposely out-scoped from the L2SM model, certain VPN parameters are listed here nevertheless. The information here can then be passed to other elements in the whole automation eco-system, such as the configuration engine, which will handle the actual service provisioning function.

The "signaling-option" list uses "name" and "type" combination as the key. The "name" leaf is a free-form string of the VPN instance name. The "type" leaf is for the signaling protocol: BGP-L2VPN, BGP-EVPN, or T-LDP.

5.1.2.4.1. BGP L2VPN

[RFC4761] and [RFC6624] describe the mechanism to auto-discover L2VPN VPLS/VPWS end points (CE-ID or VE-ID) and signal the label base and offset at the same time to allow remote PE to derive the VPN label to be used when sending packets to the advertising router.

Due to the auto-discovery natural, PEs that have at least one attachment circuit associated with a particular VPN service do not need to be specified explicitly.

In the L2SM model, only the target community (or communities) will be listed at the service level.

The "type" leaf under "mp-bgp-l2vpn" is an identityref to specify "vpws" or "vpls" sub-types.

5.1.2.4.2. BGP EVPN

Defined in [RFC7432], EVPN is a new promising L2VPN technology based upon BGP MAC routing. It's considered the next generation L2VPN solution that provides similar functionality of BGP VPWS/VPLS with improvement around redundancy, multicast optimization, provisioning and simplicity.

Due to the auto-discovery natural, PEs that have at least one attachment circuit associated with a particular VPN service do not need to be specified explicitly.

In the L2SM model, only the target community (or communities) will be listed at the service level.

The "type" leaf under "mp-bgp-evpn" is an identityref to specify "vpws" or "vpls" sub-types.

5.1.2.4.3. LDP Pseudowires

[RFC4762] specified the method of using targeted LDP sessions between PEs to exchange VC label information. This requires a manually define a full mesh of targeted LDP sessions between all PEs.

As multiple attachment circuits may terminate on a single PE, this PE-to-PE mesh is not a per site attribute. All PEs related to the L2VPN service will be listed in the "t-ldp-pwe" with associated "vc-id".

5.1.2.4.4. PWE Encapsulation Type

Based on [RFC4448], there are two types of Ethernet services: "Port-to-Port Ethernet PW emulation" and "Vlan-to-Vlan Ethernet PW emulation", commonly referred to as Type 5 and Type 4 respectively. This concept applies to both BGP L2VPN VPWS/VPLS and T-LDP signaled PWE implementations.

The "pwe-encapsulation-type" container contains two Boolean type leaves: "ethernet" and "ethernet-vlan", only one should be marked TRUE if "signaling-option" is "mp-bgp-l2vpn" or "t-ldp-pwe".

5.1.2.4.5. PWE MTU

During the signaling process of BGP-l2VPN or T-LDP pseudowire, the pwe-mtu value is exchanged and must match on both ends. By default, the pwe-mtu is derived from physical interface MTU of the attachment circuit minus the EoMPLS transport header. In some cases, however, the physical interface on both ends of the circuits may not have identical MTU settings. For example, due to 802.1ad q-in-q operation, I-NNI interface will need extra four bytes to accommodate the S-tag. The inter-carrier E-NNI link may also have a different MTU size then the internal network interfaces.

[RFC4448] requires same MTU size on physical interface on both end of the pseudowire. In actual implementations, many router vendors have provided the knob to explicitly specify the pwe-mtu, which can then be decoupled from the physical interface MTU.

When there's a mismatch between the physical interface MTU and configured pwe-mtu, "allow-mtu-mismatch" knob is also required in many cases.

The optional "pwe-mtu" container is for this purpose.

5.1.2.4.6. Control Word

A control word is an optional 4-byte field located between the MPLS label stack and the Layer 2 payload in the pseudowire packet. It plays a vital role in Any Transport over MPLS (AToM). The 32-bit field carries generic and Layer 2 payload-specific information, including a C-bit which indicates whether the control word will present in the Ethernet over MPLS (EoMPLS) packets. If the C-bit is set to 1, the advertising PE expects the control word to be present in every pseudowire packet on the pseudowire that is being signaled. If the C-bit is set to 0, no control word is expected to be present.

Whether to include control word in the pseudowire packets MUST match on PEs at both ends of the pseudowire and it's non-negotiable during the signaling process.

Control-word applies to both BGP L2VPN VPWS/VPLS and T-LDP signaled PWE implementations. It is a routing-instance level configuration in many cases.

The optional "control-word" leaf is a Boolean field in the L2SM model for the provider to explicitly specify whether control-word will be signaled for the service instance.

5.1.2.5. Load Balance Option

As the subscribers start to deploy more 10G or 100G Ethernet equipment in their network, the demand for high bandwidth Ethernet services increases. Along with the great revenue opportunities, these high bandwidth service requests also pose challenges on capacity planning and service delivery in the provider's network. Especially when the contractual bandwidth is at, or close to, the speed of physical link of the service provider's core network. Because of the encapsulation overhead, the provider can not deliver the throughput in the service level agreement over a single link. Although there may be bundled Nx10G or Nx100G aggregation links between core network elements, or Equal Cost Multiple Paths (ECMP) in the network, an EoMPLS PWE or VxLAN circuit is considered a single flow to a router or switch which uses the five tuples in the hashing algorithm.

Without burdening the core routers with additional processing of deep inspection into the payload, the service provider now have the option of inserting flow or entropy label into the EoMPLS frames, or using different source UDP ports in case of VxLAN/EVPN, at ingress PE to facility load-balancing on the subsequent nodes along the path. The ingress PE is in a unique position to see the actual unencapsulated service frames and identify data flows based on the original Ethernet and IP header.

On the other hand, not all Layer 2 Ethernet VPNs is suited for load-balancing across diverse ECMP paths. For example, a Layer 2 Ethernet service transported over a single RSVP signaled LSP will not take multiple ECMP paths. Or if the subscriber is concerned about latency/jitter then diverse path load-balance can be undesirable.

The optional "load-balance-option" container is intended to capture the load-balance agreement between the subscriber and provider. If the "load-balance" Boolean leaf is marked TRUE, then one of the following load-balance methods can be selected: "fat-pw", "entropy-label", or "vxland-source-udp-port".

5.1.2.6. SVLAN ID Ethernet Tag

Service providers have the option of inserting an outer VLAN tag (the S-tag) into the service frames from the subscriber to improve service scalability and customer VLAN transparency.

Ideally, all external interfaces (UNI and E-NNI) associated with a given service will have the same S-tag assigned. However, this may not always be the case. Traffic with all attachments using different S-tags will need to be "normalized" to a single service S-tag. (One example of this is a multipoint service involves multiple off-net OVCs terminating on the same E-NNI interface. Each of these off-net OVCs will have a distinct S-tag, which can be different from the S-tag used in the on-net part of the service.)

The purpose of the optional "svlan-id-ethernet-tag" leaf is to identify the service-wide "normalized S-tag".

5.1.2.7. CVLAN ID To EVC MAP

When more than one services are multiplexed on the same UNI interface, ingress service frames are conditionally transmitted through one of the EVC/OVCs based upon pre-arranged customer VLAN to EVC mapping. Multiple customer VLANs can be bundled across the same EVC.

"cvlan-id-to-evc-map", when applicable, contains the list of customer vlans to the service mapping in a free-form format. In most cases, this will be the VLAN access-list for the inner 802.1q tags (the C-tag).

5.1.2.8. Service Level MAC Limit

When multiple services are provided on the same network element, MAC address table, and RIB space for MAC-routes in case of EVPN, are shared common resource. Service providers may impose a maximum number of MAC learned from the subscriber for a single service instance, and specify the action when the upper limit is violated: drop the packet, flood the packet, or simply send a warning log message.

For point-to-point services, if MAC learning is disabled then MAC limit is not necessary in this kind of implementation.

The optional "service-level-mac-limit" container contains the subscriber MAC address limit and exceeding action information.

5.1.2.9. Service Protection

Sometimes the subscriber may desire end-to-end protection at the service level for applications with high availability requirements. There are two protection schemes to offer redundant services:

• 1+1 protection: In this scheme, the primary EVC or OVC will be protected by a backup EVC or OVC, typically meet certain diversified path/fiber/site/node criteria. Both primary and protection circuits are provisioning to be in forwarding state. Subscriber may choose to send the same service frames across both circuits simultaneously.
• 1:1 protection: In this scheme, a backup circuit can be provisioning to the primary circuits. Depending on the implementation agreement, the protection circuits may either always be in forwarding state, or only become active when detecting a faulty state or the primary circuit.

The optional "service-protection" container hereby is to capture the desired service protection agreement between subscriber and provider.

An "peer-evc-id" should be specified when the "protection-model" has value.

5.1.3. site

The "site" container is intended for the provider to store information of detailed implementation arrangement with either the subscriber or peer operators at each inter-connect location.

We are restricting the L2SM to exterior interfaces only. All internal interfaces or the underlying topology is outside the scope of L2SM.

There are possibly two types of external facing connections associated with an Ethernet VPN service:

• UNI site: where a customer edge device connects to one or more VPN services.
• E-NNI site: where two Ethernet service providers inter-connect with each other.

These two kinds of site are presented in the L2SM model. For each site, there are sub-containers to maintain physical link attributes, service frame and Layer 2 control protocol frame disposition, Ethernet service OAM attributes, and service bandwidth profile and priority level agreement.

5.1.3.1. uni-site

The User Network Interface (UNI) is the physical demarcation point between the service provider and subscriber.

Typically, the following characteristics of the UNI handoff needs to be documented as part of the service design:

Unique identifier (site-id) :

An arbitrary string to uniquely identify the site within the overall network infrastructure. The format of site-id is determined by the local administration of the VPN service.

Location (location) :

The site location information to allow easy retrieval on nearest available resources.

Site diversity (site-diversity) :

Presents some parameters to support site diversity.

Management (management) :

Defines the model of management of the site, for example: type, management-transport, address.

UNI ports (uni-ports) :

Defines the list of uni-ports to the sites and their properties.

5.1.3.1.1. Site ID

The "site-id" leaf contains an arbitrary string to uniquely identify the site within the overall network infrastructure. The format of the site-id is determined by the local administration of the VPN service.

5.1.3.1.2. Site Management

The "management" sub-container is intended for site management options, depending on the device ownership and security access control. The followings are three common management models:

ce-provider-managed :

The provider has the sole ownership of the CE device. Only the provider has access to the CE. The responsibility boundary between SP and customer is between CE and customer network. This is the most common use case.

ce-customer-managed :

The customer has the sole ownershop of the CE device. Only the customer has access to the CE. In this model, the responsibility boundary between SP and customer is between PE and CE.

ce-co-managed :

The provider has ownership of the CE device and responsible for managing the CE. However, the provider grant the customer accessing the CE for some configuration/monitoring purpose. In this co-managed mode the responsibility boundary is the same as the provider-managed model.

The selected management mode is specified under the "type" leaf. The "address" leaf stores CE device management IP information. And " management-transport" leaf is used to identify the transport protocol for management traffic, IPv4 or IPv6. Additional security options MAY be derived based on the particular management model selected.

5.1.3.1.3. Site Location

The information in the "location" sub-container under a uni-site allows easy retrieval on nearest available facility for access topology planning. It may also be used by other network orchestration component to decide the targeted upstream PE.

5.1.3.1.4. Site Diversity

Some subscriber may request upstream PE diversity between two or more sites. These sites will share the same diversity group ID under the optional "site-diversity" sub-container.

5.1.3.1.5. Site Security

This sub-container is s placeholder for site-security options. It presents parameters for ingress service stream admission control and encryption profile information.

5.1.3.1.6. Site Signaling Option

See Section 5.1.2.4

5.1.3.1.7. UNI Ports

The L2SM includes a set of essential physical interface properties and Ethernet layer characteristics in the uni-port sub-container. Some of these are critical implementation arrangements that require consent from both subscriber and provider.

5.1.3.1.7.1. UNI ID

"uni-id" is an freeform string to identify a given UNI interface. Service provider can decide on the actual nomenclature used in the management systems.

5.1.3.1.7.2. Bearer

Under uni-port, there is a bearer container that presents two sets of link attributes: physical or optional LAG interface attributes. These parameters are essential for the connection between subscriber and provider edge devices to establish properly.

For each physical interface, there're basic configuration parameters like port number and speed, interface face MTU, auto-negotiation and flow-control settings, etc. "encapsulation-type" is for user to select between Ethernet encapsulation (port-based) or Ethernet VLAN encapsulation (VLAN-based). All allowed ethertypes of ingress service frames can be listed under "ethertype". In addition, the subscriber and provider may decide to enable advanced features, such as lldp, 802.3AH link OAM, MAC loop detection/prevention, based on mutual agreement.

Sometimes the subscriber may require multiple physical links bundled together to form single logical point-to-point LAG connection to the service provider. Typically, LACP (Link Aggregation Control Protocol) is used to dynamically manage adding or deleting member links of the aggregate group. In general, LAG allows for increased service bandwidth beyond the speed of a single physical link while providing graceful degradation as failure occurs, thus increased availability.

In the L2SM, there is a set of attributes under "LAG-interface" related to link aggregation functionality. The subscriber and provider first need to decide on whether LACP PDU will be exchanged between the edge device by specifying the "LACP-state" to "On" or "Off". If LACP is to be enabled, then both parties need to further specify whether it will be running in active versus passive mode, plus the time interval and priority level of the LACP PDU. Subscriber and provider can also determine the minimum aggregate bandwidth for a LAG group to be considered valid path by specifying the optional "mini-link" attribute. To enable fast detection of faulty links, Micro-BFD runs independent UDP sessions to monitor the status of each member link. Subscriber and provider should consent to the BFD hello interval and holdtime.

Each member link will be listed under the LAG interface with basic physical link properties. Certain attributes like flow-control, encapsulation type, allowed ingress ethertype and LLDP settings are at the LAG level.

If the Ethernet service is enabled on a logical unit on the UNI-N to UNI-C connection, the "sub-if-id" should be specified.

5.1.3.1.7.3. Ethernet Connection

The "Ethernet-connection" container presents site specific (S-tag, C-tag) management options. The overall S-tag for the Ethernet circuit and C-tag to EVC mapping, if applicable, has been placed in the service container. The S-tag under UNI-port should match the S-tag in service container in most cases. However, vlan translation is required for the S-tag in certain deployment at the external facing interface or upstream PEs to "normalize" the outer VLAN tag to the service S-tag into the network and translate back to the UNI-site S-tag in the opposite direction. One example of this is, with Layer 2 aggregation switch alone the path, the S-tag for the EVC has been previously assigned to another service thus can not be used by this attachment circuit. Another use case is when multiple E-access OVCs from the same E-NNI interfaces are attached to the same E-LAN service.

The "svlan-id-ethernet-tag" in the "Ethernet-connection" container is either the S-tag inserted at a UNI or the outer tag of ingress packets at an E-NNI. These parameters are included in the L2SM to facilitate other management system to generate proper configuration for the network elements.

"Ethernet-connection" container also contains optional site-specific C-tag to EVC mapping.

5.1.3.1.7.4. Port-wide Ethernet OAM

***TBD*** Need text?

5.1.3.1.7.5. EVC MTU

The maximum MTU of subscriber service frames can be derived from the physical interface MTU by default, or specified under the "evc-mtu" leaf if it is different than the default number.

5.1.3.1.7.6. MAC Address Limit

The service provider may choose to impose a per attachment circuit "mac-addr-limit" in addition to the service-lever MAC limit, and specify the exceeding options accordingly.

5.1.3.1.7.7. Multihoming

EVPN supports PE geo-redundancy in the access domain. The connection between a multi-homed CE to PE is identified with a uniquely assigned ID referred as ESI (Ethernet Segment Identifier). Because of learned MAC address is propagated via BGP, it allows for multiple active paths in forwarding state and load-balancing options.

The "multihoming" container contains ESI and redundancy mode attribute for EVPN multi-homing site.

5.1.3.1.7.8. UNI L2CP-Control

To facilitate interoperability between different MSOs, MEF has provided normative guidance on Layer 2 control protocol (L2CP) processing requirements for each service type. Subscriber and provider should make pre-arrangement on whether to allow interaction between the edge device or keep each others control plane separate on a per protocol base.

The destination MAC addresses of these L2CP PDUs fall within two reserved blocks specified by IEEE 802.1 Working Group. Packet with destination MAC in these multicast ranges has special forwarding rules.

• Bridge Block of Protocols: 01-80-C2-00-00-00 through 01-80-C2-00-00-0F
• MRP Block of Protocols: 01-80-C2-00-00-20 through 01-80-C2-00-00-2F

Layer 2 protocol tunneling allows service providers to pass subscriber Layer 2 control PDUs across the network without being interpreted and processed by intermediate network devices. These L2CP PDUs are transparently encapsulated across the MPLS-enabled core network in Q-in-Q fashion.

The "L2CP-control" container contains the list of commonly used L2CP protocols. Service provider can specify DISCARD, PEER or TUNNEL action for each individual protocol.

In addition, "provider-bridge-group" and "provider-bridge-mvrp" addresses are also listed in the L2CP container.

5.1.3.1.7.9. Service Profile

In MEF 23.1 ([MEF-23-1]) two types of model are defined as the following:

Class-of-Service Identifier based on EVC or OVC EP (End Point):

In this model, regardless of customer marking, all in-profile frames will be marked with service level in contractual agreement. Customer CoS markings are preserved throughout the provider network. The bandwidth profile consists of one set of CIR/CBS and EIR/EBS values.

Class-of-Service Identifier based on Priority Code Point:

Using this model, multiple classes of services can be associated with a single customer EVC, identified by dot1p bits in the C-tag. Each service level has its own individual bandwidth profile. Out-of-profile packets will be discarded. Customer CoS markings are preserved.

Class-of-Service Identifier based on DSCP:

Using this model, multiple classes of services can be associated with a single customer EVC, identified by DSCP bits in the IP header. Each service level has its own individual bandwidth profile. Out-of-profile packets will be discarded. Customer CoS markings are preserved.

Similarly, Color-identifier can be assigned based on EVC or OVC EP, dot1p value in C-tag, or DSCP in IP header. Ingress service frames are metered against the bandwidth profile based on the cos-identifier. A "color" will be assigned to a service frame to identify its bandwidth profile conformance. A service frame is "green" if it is conformant with "committed" rate of the bandwidth profile. A Service Frame is "yellow" if it is exceeding the "committed" rate but conformant with the "excess" rate of the bandwidth profile. Finally, a service frame is "red" if it is conformant with neither the "committed" nor "excess" rates of the bandwidth profile.

Ingress/egress-bandwidth-profile-per-evc presents the ingress/egress bandwidth profile per EVC, providing rate enforcement for all ingress service frames at the UNI that are associated with a particular EVC.

Alternately, ingress/egress-bandwidth-profile-per-cos-id presents the ingress/egress bandwidth profile per CoS, providing rate enforcement for all service frames for a given class of service. The class of service is identified via a CoS identifier. So this bandwidth profile applies to service frames over an EVC with a particular CoS value. Multiple ingress/egress-bandwidth-profile-per-cos-id can be associated with the same EVC.

The optional "byte-offset" indicates how many bytes in the service frame header are excluded from rate enforcement.

5.1.3.1.7.10. BUM Strom Control

For point-to-point E-LINE services, the provider only needs to deliver a single copy of each service frame to the remote PE, regardless whether the destination MAC address of the incoming frame is unicast, multicast or broadcast. Therefore, all in-profile service frames should be delivered unconditionally.

B-U-M (Broadcast-UnknownUnicast-Multicast) frame forwording in multipoint-to-multipoint services, on the other hand, involves both local flooding to other attachment circuits on the same PE and remote replication to all other PEs, thus consumes additional resources and core bandwidth. Special B-U-M frame disposition rules can be implemented at external facing interfaces (UNI or E-NNI) to rate-limit the B-U-M frames, in term of number of packets per second or bits per second.

The threshold can apply to all B-U-M traffic, or one for each category.

5.1.3.1.7.11. MAC Loop Protection

MAC address flapping between different physical ports typically indicates a bridge loop condition in the subscriber network. Misleading entries in the MAC cache table can cause service frames to circulate around the network indefinitely and saturate the links throughout the provider's network, affecting other services in the same network. In case of EVPN, it also introduces massive BGP updates and control plane instability.

Service provider may opt to implement switching loop prevention mechanism at the external facing interfaces for multipoint-to-multipoint services by imposing a MAC address move threshold.

The MAC move rate and prevention-type options are listed in the "mac-loop-prevention" container.

5.1.3.1.7.12. Ethernet Service OAM

The advent of Ethernet as wide-area network technology brings additional requirements of end-to-end service monitoring and fault management in the carrier network, particularly in the area of service availability and Mean Time To Repair (MTTR). Ethernet Service OAM in the L2SM refers to the combined protocol suites of IEEE 802.1ag ([IEEE-802-1ag]) and ITU-T Y.1731 ([ITU-T-Y-1731]).

Generally speaking, Ethernet Service OAM enables service provider to perform service continuity check, fault-isolation, and packet delay/jitter measurement at per customer per EVC granularity. The information collected from Ethernet Service OAM datasets is complementary to other higher layer IP/MPLS OSS tools to ensure the required service level agreements (SLAs) can be meet.

The 802.1ag Connectivity Fault Management (CFM) functional model is structured with hierarchical maintenance domains (MD), each assigned a unique maintenance level. Higher level MD can be nested over lower level MD. However, the MD can not intersect. The scope of each MD can be solely within a subscriber's network, solely within the provider's network, interact between the subscriber-to-provider or provider-to-provider edge equipment, or tunnel over another provider's network.

Depending on the use case scenario, one or more maintenance end point (MEP) can be placed on the external facing interface, sending CFM PDUs towards the core network (UP MEP) or downstream link (DOWN MEP).

The "cfm-802.1-ag" sub-container under UNI-port currently presents two types of CFM maintenance association (MA): UP MEP for UNI-N to UNI-N MA and DOWN MEP for UNI-N to UNI-C MA. For each MA, user can define the maintenance domain ID (MAID), MEP level, MEP direction, remote MEP ID, CoS level of the CFM PDUs, Continuity Check Message (CCM) interval and holdtime, alarm priority defect, CCM priority-type, etc.

ITU-T Y.1731 Performance Monitoring (PM) provides essential network telemetry information that includes the measurement of Ethernet service frame delay, frame delay variation, frame loss, and frame throughput. The delay/jitter measurement can be either one-way or two-way. Typically, a Y.1731 PM probe sends a small amount of synthetic frames along with service frames to measure the SLA parameters.

The "y-1731" sub-container under UNI-port contains a set of parameters for use to define the PM probe information, including MAID, local and remote MEP-ID, PM PDU type, message period and measurement interval, CoS level of the PM PDUs, loss measurement by synthetic or service frame options, one-way or two-way delay measurement, PM frame size, and session type.

5.1.3.2. enni-site

5.1.3.2.1. Site Management

5.1.3.2.2. Site Location

5.1.3.2.3. Site Diversity

5.1.3.2.4. Site Security

5.1.3.2.5. Site Service

5.1.3.2.6. Site Protection

5.1.3.2.7. ENNI Signaling Options

5.1.3.2.8. ENNI Port

5.1.3.2.8.1. ENNI Bearer

5.1.3.2.8.2. ENNI Multihoming

5.1.3.2.8.3. ENNI L2CP Control

5.1.3.2.8.4. ENNI Ethernet Service OAM

6. Interaction with Other YANG Modules

As expressed in Section 4, this service module is not intended to configure the network element, but is instantiated in a management system.

The management system might follow modular design and comprise at least two different components:

1. The component instantiating the service model (let's call it the service component)
2. The component responsible for network element configuration (let's call it the configuration component)

In some cases when the split is needed between the behavior and functions that a customer requests and the technology that the network operator has available to deliver the service [I-D.wu-opsawg-service-model-explained]. A new component can be separated out of the service component (let's call it the control component). This component is responsible for network-centric operation and is aware of many features such as topology, technology, and operator policy. As an optional component, it can use service model as input and is not required if the control component delegates its control operations to the configuration component.

In Section 7 we provide some example of translation of service provisioning request to router configuration lines as an illustration. In the NETCONF/YANG ecosystem, it is expected that NETCONF and YANG will be used between the configuration component and network elements to configure the requested service on those elements.

In this framework, it is expected that YANG models will be used for configuring service components on network elements. There will be a strong relationship between the abstracted view provided by this service model and the detailed configuration view that will be provided by specific configuration models for network elements such as those defined in [I-D.ietf-bess-l2vpn-yang] and [I-D.ietf-bess-evpn-yang]. Service components needing configuration on network elements in support of the service model defined in this document include:

• VRF definition including VPN policy expression.
• Physical interface.
• Ethernet layer (VLAN ID).
• QoS : classification, profiles, etc.
• Routing protocols : support of configuration of all protocols listed in the document, as well as routing policies associated with these protocols.
• Multicast Support.
• Ethernet Service OAM Support.

7. Service Model Usage Example

*** TBD ***

8. YANG Module

          
<CODE BEGINS> file "ietf-l2vpn-svc@2016-09-29.yang"
module ietf-l2vpn-svc {

   namespace "urn:ietf:params:xml:ns:yang:ietf-l2vpn-svc";

   prefix "l2svc";

   import ietf-inet-types {
     prefix inet;
   }

   import ietf-yang-types {
        prefix yang;
   }

   organization
     "IETF L2SM Working Group.";

   contact
     "WG List: l3sm@ietf.org
      Editor: Bin_Wen@comcast.com";

   description
     "The YANG module defines a generic service configuration
      model for Layer 2 VPN services common across all of the
      vendor implementations.";

   revision 2016-09-09{
     description
       "Initial revision.";
     reference
       "draft-wen-l2sm-l2vpn-service-model-01.txt
        A YANG Data Model for L2VPN Service Delivery.";
   }

   /* Features */

   feature oam-3ah {
     description
       "Enables support of oam 802.3ah";
   }

   feature Micro-BFD {
     description
       "Enables support of Micro-BFD";
   }

   feature bfd {
     description
       "Enables support of bfd";
   }

   feature signaling-option {
     description
       "Enable support of signaling option";
   }

   feature site-diversity {
     description
       "Enables support of site diversity constraints";
   }

   feature encryption {
       description
         "Enables support of encryption";
     }

   /* Typedefs */

   typedef ccm-priority-type {
     type uint8 {
     range "0..7";
     }
     description
     "A 3 bit priority value to be used in the VLAN tag, if present
      in the transmitted frame.";
    }

   typedef control-mode {
     type enumeration{
       enum peer{
         description
           "Peer mode";
     }
     enum tunnel {
       description
         "Tunnel mode";
     }
     enum discard {
       description
         "Discard mode";
     }
    }
    description
      "Defining a type of the control mode";
   }

   /* Identities */

   identity color-id {
     description
      "Identity of color id";
   }

   identity color-id-evc {
     base color-id;
     description
       "Identity of color id base on EVC";
   }

   identity color-id-evc-cvlan {
     base color-id;
     description
      "Identity of color id base on EVC and CVLAN ";
   }

   identity cos-id {
     description
       "Identity of class of service id";
   }

   identity cos-id-evc {
     base cos-id;
     description
       "Identity of cos id based on EVC";
   }

   identity cos-id-ovc-ep {
     base cos-id;
     description
       "Identity of cos id based on OVC End Point";
   }

   identity cos-id-evc-pcp {
     base cos-id;
     description
       "Identity of cos id based on EVC and PCP";
   }

   identity cos-id-evc-dscp {
     base cos-id;
     description
       "Identity of cos id based on EVC and DSCP";
   }

   identity performance-tier-option {
     description
       "Identity of performance tier option.";
   }

   identity metro {
     base performance-tier-option;
     description
       "Identity of metro";
   }

   identity regional {
     base performance-tier-option;
     description
       "Identity of regional";
   }

   identity continental {
     base performance-tier-option;
     description
      "Identity of continental";
   }

   identity global {
     base performance-tier-option;
     description
       "Identity of global";
   }

   identity policing {
     description
       "Identity of policing type";
   }

   identity one-rate-two-color {
     base policing;
     description
       "Identity of one-rate, two-color (1R2C)";
   }

   identity two-rate-three-color {
     base policing;
     description
       "Identity of two-rate, three-color (2R3C)";
   }

   identity BUM-type {
     description
       "Identity of BUM type";
   }

   identity broadcast {
     base BUM-type;
     description
       "Identity of broadcast";
   }

   identity unicast {
     base BUM-type;
     description
       "Identity of unicast";
   }

   identity multicast {
     base BUM-type;
     description
       "Identity of multicast";
   }

   identity loop-prevention-type{
     description
       "Identity of loop prevention";
   }

   identity shut {
     base loop-prevention-type;
     description
       "Identity of shut protection";
   }

   identity trap {
     base loop-prevention-type;
     description
       "Identity of trap protection";
   }

   identity lacp-state {
     description
       "Identity of lacp state";
   }

   identity lacp-on {
     base lacp-state;
     description
       "Identity of lacp on";
   }

   identity lacp-off {
     base lacp-state;
     description
       "Identity of lacp off";
   }

   identity lacp-mode {
     description
       "Identity of lacp mode";
   }

   identity lacp-passive {
     base lacp-mode;
     description
       "Identity of lacp passive";
   }

   identity lacp-active {
     base lacp-mode;
     description
       "Identity of lacp active";
   }

   identity lacp-speed {
     description
       "Identity of lacp speed";
   }

   identity lacp-fast {
     base lacp-speed;
     description
       "Identity of lacp fast";
   }

   identity lacp-slow {
     base lacp-speed;
     description
       "Identity of lacp slow";
   }

   identity vpn-signaling-type {
      description
        "Identity of vpn signaling types";
   }

   identity vrf {
     base vpn-signaling-type;
     description
       "Virtual routing and forwarding (VRF).";
   }

   identity vfi {
     base vpn-signaling-type;
     description
       "Virtual forwarder interface";
   }

   identity evi {
     base vpn-signaling-type;
     description
       "Ethernet virtual interconnect.";
   }

   identity l2vpn-type {
     description
       "Layer 2 VPN types";
   }

   identity vpws {
     base l2vpn-type;
     description
       "Virtual Private Wire Service";
   }

   identity vpls {
     base l2vpn-type;
     description
       "Virtual Private LAN Service";
   }

   identity evpn {
     base l2vpn-type;
     description
       "Ethernet VPN";
   }

   identity management {
     description
       "Base identity for site management scheme.";
   }

   identity co-managed {
     base management;
     description
       "Base identity for comanaged site.";
   }

   identity customer-managed {
     base management;
     description
       "Base identity for customer managed site.";
   }

   identity provider-managed {
     base management;
     description
       "Base identity for provider managed site.";
   }

   identity address-family {
     description
       "Base identity for an address family.";
   }

   identity ipv4 {
     base address-family;
     description
       "Identity for IPv4 address family.";
   }

   identity ipv6 {
     base address-family;
     description
       "Identity for IPv6 address family.";
   }

   identity vpn-topology {
     description
       "Base identity for VPN topology.";
   }

   identity any-to-any {
     base vpn-topology;
     description
       "Identity for any to any VPN topology.";
   }

   identity hub-spoke {
     base vpn-topology;
     description
       "Identity for Hub'n'Spoke VPN topology.";
   }

   identity hub-spoke-disjoint {
     base vpn-topology;
     description
       "Identity for Hub'n'Spoke VPN topology
        where Hubs cannot talk between each other.";
   }

   identity site-role {
     description
       "Base identity for site type.";
   }

   identity any-to-any-role {
     base site-role;
     description
       "Site in an any to any IPVPN.";
   }

   identity spoke-role {
     base site-role;
     description
       "Spoke Site in a Hub & Spoke IPVPN.";
   }

   identity hub-role {
     base site-role;
     description
       "Hub Site in a Hub & Spoke IPVPN.";
   }

   identity pm-type {
     description
       "Performance monitor type";
   }

   identity loss {
     base pm-type;
     description
       "Loss measurement";
   }

   identity delay {
     base pm-type;
     description
       "Delay measurement";
   }

   identity fault-alarm-defect-type {
     description
       "Indicating the alarm priority defect";
   }

   identity remote-rdi {
     base fault-alarm-defect-type;
     description
       "Indicates the aggregate health of the remote MEPs.";
   }

   identity remote-mac-error {
     base fault-alarm-defect-type;
     description
       "Indicates that one or more of the remote MEPs is
        reporting a failure in its Port Status TLV or
        Interface Status TLV.";
   }

   identity remote-invalid-ccm {
     base fault-alarm-defect-type;
     description
       "Indicates that at least one of the Remote MEP
        state machines is not receiving valid CCMs
        from its remote MEP.";
    }

    identity invalid-ccm {
      base fault-alarm-defect-type;
      description
        "Indicates that one or more invalid CCMs has been
         received and that 3.5 times that CCMs transmission
         interval has not yet expired.";
    }

    identity cross-connect-ccm {
      base fault-alarm-defect-type;
      description
        "Indicates that one or more cross connect CCMs has been
         received and that 3.5 times of at least one of those
         CCMs transmission interval has not yet expired.";
    }

   /* Groupings */

   grouping customer-info-grouping {
     list customer-info {
       key "customer-account-number customer-name";
       leaf customer-account-number {
         type uint32;
         description
           "Customer account number";
       }
       leaf customer-name {
         type string;
         description
           "Customer name";
       }
       container customer-operation-center {
         leaf customer-noc-street-address {
           type string;
           description
             "Customer NOC street Address.";
         }
         container customer-noc-phone-number {
           leaf main-phone-num {
             type uint32;
             description
               "Main phone number.";
           }
           leaf extension-options {
             type uint32;
             description
               "Extension or options";
           }

           description
             "Configuration of customer noc phone number";
         }
         description
           "Configuration of customer operation center";
       }
       description
         "List of customer information";
     }
     description
       "Grouping for customer information";
   }

   grouping site-management {
     container management {
       leaf site-name {
         type string;
         description
           "Site name";
       }
       leaf address {
         type inet:ip-address;
         description
         "Address";
       }
       leaf ce-device-info {
         type string;
         description
           "CE device info";
       }
       leaf type {
         type identityref {
           base management;
         }
         description
           "Management type of the connection.";
       }
       leaf management-transport {
         type identityref {
           base address-family;
         }
         description
           "Transport protocol used for management.";
       }
       description
         "Management configuration";
     }
     description
       "Management parameters for the site.";
   }

   grouping customer-location-info {
     container location {
       leaf address {
         type string;
         description
           "Address (number and street) of the site.";
       }
       leaf zip-code {
         type string;
         description
           "ZIP code of the site.";
       }
       leaf state {
         type string;
         description
           "State of the site. This leaf can also be used to
           describe a region for country who does not have
           states.";
       }
       leaf city {
         type string;
         description
           "City of the site.";
       }
       leaf country-code {
         type string;
         description
           "Country of the site.";
       }
       description
         "Location of the site.";
     }
     description
       "This grouping defines customer location parameters";
    }

    grouping site-diversity {
      container site-diversity {
        if-feature site-diversity;
        container groups {
          list group {
            key group-id;
            leaf group-id {
              type string;
              description
                "Group-id the site is belonging to";
              }
            description
              "List of group-id";
          }
          description
            "Groups the site is belonging to.
             All site network accesses will inherit those group
             values.";
        }
        description
          "Diversity constraint type.";
      }
      description
        "This grouping defines site diversity parameters";
    }

    grouping site-service{
      leaf svlan-id-ethernet-tag {
        type string;
         description
           "SVLAN-ID/Ethernet Tag configurations";
      }
      leaf cvlan-id-to-evc-map {
        type string;
        description
          "List of CVLAN-ID to EVC Map configurations";
      }
      leaf service-level-mac-limit {
        type string;
        description
          "Service-level MAC-limit (E-LAN only)";
      }
      description
        "This grouping defines site service parameters";
    }

    grouping service-protection{
      container service-protection {
        container protection-model {
          description
            "Container of protection model configurations";
        }
        container peer-evc-id {
          description
            "Container of peer evc id configurations";
        }
        description
          "Container of End-to-end Service Protection
          configurations";
      }
      description
        "Grouping for service protection";
    }

    grouping ethernet-service-type {
      choice ethernet-svc-type {
        case e-line {
          leaf epl {
            type boolean;
            description
              "Ethernet private line";
          }
          leaf evpl {
            type boolean;
            description
              "Ethernet virtual private line";
          }
          description
            "Case of e-line";
        }

        case e-lan {
          leaf ep-lan {
            type boolean;
            description
              "Ethernet private LAN";
          }
          leaf evp-lan {
            type boolean;
            description
              "Ethernet virtual private LAN";
          }
          description
            "Case of e-lan";
        }
        case e-access {
          leaf access-epl {
            type boolean;
            description
              "Access Ethernet virtual private line";
          }
          leaf access-evpl {
            type boolean;
            description
              "Access Ethernet virtual private line";
          }
          description
            "Case of e-access.";
        }
        description
          "Choice of Ethernet service type";
      }
      description
        "Grouping for Ethernet service type.";
    }

    grouping signaling-option-grouping {
      list signaling-option {
        key "name type";
        leaf name {
          type string;
          description
            "VRF/VFI/EVI Name";
        }
        leaf type {
          type identityref {
            base vpn-signaling-type;
          }
          description
            "VPN signaling types";
        }
        container mp-bgp-l2vpn {
            leaf vpn-id {
              type string;
              description
                "Identifies the target VPN";
            }
            leaf type {
              type identityref {
                base l2vpn-type;
              }
              description
                "L2VPN types";
            }
          description
          "Container for MP BGP l2VPN";
        }

        container mp-bgp-evpn {
            leaf vpn-id {
              type string;
              description
                "Identifies the target VPN";
            }
            leaf type {
              type identityref {
                base l2vpn-type;
              }
              description
                "L2VPN types";
            }
          description
          "Container for MP BGP l2VPN";
        }

        container t-ldp-pwe {
          list PE-EG-list {
            key "service-ip-lo-addr vc-id";
            leaf service-ip-lo-addr {
              type inet:ip-address;
              description
                "Service ip lo address";
            }
            leaf vc-id {
              type string;
              description
              "VC id";
            }
            description
              "List of PE/EG";
          }
          description
            "Container of T-LDP PWE configurations";
        }

        container pwe-encapsulation-type {
          leaf ethernet {
            type boolean;
            description
              "Ethernet";
          }
          leaf vlan {
            type boolean;
            description
              "VLAN";
          }
          description
          "Container of PWE Encapsulation Type configurations";
        }

        container pwe-mtu {
          leaf allow-mtu-mismatch {
            type boolean;
            description
              "Allow MTU mismatch";
          }
          description
          "Container of PWE MTU configurations";
        }

        container control-word {
          description
            "Container of control word configurations";
        }

        description
          "List of VPN Signaling Option.";
      }

      description
        "Grouping for signaling option";
    }

   grouping load-balance-grouping {
     leaf fat-pw {
       type boolean;
       description
         "Fat label is applied to Pseudowires across MPLS
         network";
     }
     leaf entropy-label {
       type boolean;
       description
         "Entropy label is applied to IP forwarding,
          L2VPN or L3VPN across MPLS network";
     }
     description
       "Grouping for load balance ";
   }

   grouping intra-mkt-grouping {
     list intra-mkt {
       key "metro-mkt-id mkt-name";
       leaf metro-mkt-id {
         type uint32;
         description
           "Metro MKT ID";
       }
       leaf mkt-name {
         type string;
         description
           "MKT Name";
       }
       description
         "List of intra-MKT";
     }
     description
       "Grouping for intra-MKT";
   }

   grouping inter-mkt-service {
     leaf inter-mkt-service{
       type boolean;
       description
         "Indicate whether service is inter market service.";
     }
     description
       "Grouping for inter-MKT service";
   }

   grouping evc-id-grouping {
     leaf evc-id {
       type boolean;
       description
         "Ethernet Virtual Connection identifier";
     }
     description
       "Grouping for EVC-ID";
   }

   grouping svc-type-grouping {
     container svc-type {
       container evc {
         leaf evc-id {
           type boolean;
           description
             "Indicate whether the Ethernet virtual connection
              id support.";
         }
         leaf max-number-of-pe {
         type uint32;
         description
           "Maximum number of PEs supported per EVC.";
         }
         leaf max-number-of-site {
           type uint32;
           description
             "Maximum number of sites supported per EVC.";
         }
         description
           "Container for Ethernet virtual connection.";
       }
       container ovc {
         leaf on-net-ovc-id {
           type boolean;
           description
             "Indicate whether the on net OVC id support.";
         }
         leaf off-net-ov-id {
           type boolean;
           description
             "Indicate whether the off net OVC id support.";
         }
         description
           "Container for OVC";
       }
       description
         "Container for service types.";
     }
     description
       "Grouping of service types.";
   }

   grouping cfm-802-grouping {

     leaf MAID {
       type string;
       description
         "MA ID";
     }

     leaf mep-id {
      type uint32;
      description
        "Local MEP ID";
     }

     leaf mep-level {
       type uint32;
       description
         "MEP level";
     }

     leaf mep-up-down {
       type enumeration {
         enum up {
           description
             "MEP up";
         }
         enum down {
           description
             "MEP down";
         }
       }
       description
         "MEP up/down";
     }

     leaf remote-mep-id {
       type uint32;
       description
         "Remote MEP ID";
     }

     leaf cos-for-cfm-pdus {
       type uint32;
       description
         "COS for CFM PDUs";
     }

     leaf ccm-interval {
       type uint32;
       description
         "CCM interval";
     }

     leaf ccm-holdtime {
       type uint32;
       description
         "CCM hold time";
     }

     leaf alarm-priority-defect {
       type identityref {
         base fault-alarm-defect-type;
       }
       description
        "The lowest priority defect that is
         allowed to generate a Fault Alarm.
         The non-existence of this leaf means
         that no defects are to be reported";
     }

     leaf ccm-p-bits-pri {
       type ccm-priority-type;
       description
         "The priority parameter for CCMs transmitted by the MEP";
     }

     description
       "Grouping for 802.1ag CFM attribute";
   }

   grouping y-1731{
     list y-1731 {
       key MAID;

       leaf MAID {
         type string;
         description
           "MA ID ";
       }

       leaf mep-id {
         type uint32;
         description
           "Local MEP ID";
       }

       leaf type {
         type identityref {
           base pm-type;
         }
         description
           "Performance monitor types";
       }

       leaf remote-mep-id {
         type uint32;
         description
           "Remote MEP ID";
       }

       leaf message-period {
         type uint32;
         description
           "Defines the interval between OAM messages. The message
            period is expressed in milliseconds";
       }

       leaf measurement-interval{
         type uint32;
         description
           "Specifies the measurement interval for statistics. The
            measurement interval is expressed in seconds";
       }

       leaf cos {
         type uint32;
         description
           "Class of service";
       }

       leaf loss-measurement {
         type boolean;
         description
           "Whether enable loss measurement";
       }

       leaf synthethic-loss-measurement {
         type boolean;
         description
           "Indicate whether enable synthetic loss measurement";
       }

       container delay-measurement {
         leaf enable-dm {
           type boolean;
           description
             "Whether to enable delay measurement";
         }
         leaf two-way {
           type boolean;
           description
             "Whether delay measurement is two-way (true) of one-
             way (false)";
         }
         description
           "Container for delay measurement";
       }

       leaf frame-size{
         type uint32;
         description
           "Frame size";
       }

       leaf session-type {
         type enumeration {
           enum proactive {
             description
               "Proactive mode";
           }
           enum on-demand {
             description
               "On demand mode";
           }
         }
         description
           "Session type";
       }

       description
         "List for y-1731.";
     }
     description
       "Grouping for y.1731";
   }

   grouping enni-site-info-grouping {
     container site-info {
       leaf site-name {
         type string;
         description
           "Site name";
       }
       leaf address {
         type inet:ip-address;
         description
           "Address";
       }
       leaf Edge-Gateway-Device-Info {
         type string;
         description
           "Edge Gateway Device Info ";
       }
       description
         "Container of site info configurations";
     }
     description
       "Grouping for site information";
   }

   grouping site-security {
     container security {
       description
         "Security parameters";
     }
     description
       "This grouping defines security parameters for a site";
   }

   grouping lacp-grouping {

     container LACP {
       leaf LACP-state {
         type identityref {
           base lacp-state;
         }
         description
           "LACP on/off";
       }
       leaf LACP-mode {
         type identityref {
           base lacp-mode;
         }
         description
           "LACP mode";
       }
       leaf LACP-speed {
         type identityref {
           base lacp-speed;
         }
         description
           "LACP speed";
       }
       leaf mini-link {
         type uint32;
         description
           "Mini link";
       }
       leaf system-priority {
         type uint16;
         description
           "Indicates the LACP priority for the system.
            The range is from 0 to 65535.
            The default is 32768.";
       }

       container Micro-BFD {
         if-feature Micro-BFD;
         leaf Micro-BFD-on-off {
           type enumeration {
             enum on {
               description
                 "Micro-bfd on";
             }
             enum off {
               description
                 "Micro-bfd off";
             }
           }
           description
             "Micro BFD ON/OFF";
         }
         leaf bfd-interval {
           type uint32;
           description
             "BFD interval";
         }
         leaf bfd-hold-timer {
           type uint32;
           description
             "BFD hold timer";
         }
         description
           "Container of Micro-BFD configurations";
       }

       container bfd {
         if-feature bfd;
         leaf bfd-enabled {
           type boolean;
           description
             "BFD activation";
         }
         choice holdtime {
           case profile {
             leaf profile-name {
               type string;
               description
                 "Service provider well
                  known profile.";
             }
             description
               "Service provider well
                known profile.";
           }
           case fixed {
             leaf fixed-value {
               type uint32;
               units msec;
               description
                 "Expected holdtime
                  expressed in msec.";
             }
           }
           description
             "Choice for holdtime flavor.";
         }
         description
           "Container for BFD.";
       }

       container Member-link-list {
         list member-link {
           key "name";
           leaf name {
             type string;
             description
               "Member link name";
           }
           leaf port-speed {
             type uint32;
             description
               "Port speed";
           }
           leaf auto-neg {
             type string;
             description
               "Auto neg";
           }
           leaf mtu {
             type uint32;
             description
               "MTU";
           }
           container oam-802.3AH-link{
             if-feature oam-3ah;
             leaf enable {
               type boolean;
               description
                 "Indicate whether support oam 802.3 ah
                  link";
             }
             description
               "Container for oam 802.3 ah link.";
           }
           description
             "Member link";
         }
         description
           "Container of Member link list";
       }

       leaf flow-control {
         type string;
         description
           "Flow control";
       }

       leaf encapsulation-type {
         type enumeration {
           enum VLAN {
             description
               "VLAN";
           }
           enum ether {
             description
               "Ethernet";
           }
         }
         description
           "Encapsulation type";
       }

       leaf ethertype {
         type string;
         description
           "Ether type";
       }

       leaf lldp {
         type boolean;
          description
            "LLDP";
        }

        description
          "LACP";
      }

      description
        "Grouping for lacp";
   }

   grouping phy-interface-grouping {
     container phy-interface {
       leaf port-number {
         type uint32;
         description
           "Port number";
       }
       leaf port-speed {
         type uint32;
         description
           "Port speed";
       }
       leaf auto-neg {
         type string;
         description
           "Auto neg";
       }
       leaf phy-mtu {
         type uint32;
         description
           "PHY MTU";
       }
       leaf flow-control {
         type string;
         description
           "Flow control";
       }
       leaf encapsulation-type {
         type enumeration {
           enum VLAN {
             description
               "VLAN";
           }
           enum Ethernet {
             description
               "Ethernet";
           }
         }
         description
           "Encapsulation-type";
       }
       leaf ethertype {
         type string;
         description
           "Ethertype";
       }
       leaf lldp {
         type boolean;
         description
           "LLDP";
       }
       container oam-802.3AH-link{
         if-feature oam-3ah;
         leaf enable {
           type boolean;
           description
             "Indicate whether support oam 802.3 ah
              link";
          }
          description
            "Container for oam 802.3 ah link.";
       }
       leaf uni-loop-prevention{
         type boolean;
         description
           "If this leaf set to truth that the port automatically
            goes down when a physical loopback is detect.";
       }

       description
         "Container of PHY Interface Attributes configurations";
     }
     description
       "Grouping for phy interface.";
   }

   grouping lag-interface-grouping{
     container LAG-interface {
       list LAG-interface {
         key "LAG-interface-number";
         leaf LAG-interface-number {
           type uint32;
           description
             "LAG interface number";
         }
         uses lacp-grouping;
         description
           "List of LAG interfaces";
       }
       description
         "Container of LAG interface attributes configuration";
     }
    description
      "Grouping for LAG interface";
   }

   grouping bearer-grouping {
     container bearer {
       uses phy-interface-grouping;
       uses lag-interface-grouping;

       leaf interface-description {
         type string;
         description
           "Interface description";
       }
       leaf sub-if-id {
         type uint32;
         description
           "Sub-if id";
       }

       description
         "Container for bearer";
     }
     description
     "Grouping for bearer.";
   }

   grouping ethernet-connection-grouping {
     container ethernet-connection {
       container vlan {
         leaf svlan-id-ethernet-tag {
           type string;
           description
             "SVLAN-ID/Ethernet Tag configurations";
         }
         description
           "Abstract container for VLAN";
       }
       description
         "Container for Ethernet connection";
     }
     description
       "Grouping for Ethernet connection";
   }

   grouping evc-mtu-grouping {
     leaf evc-mtu {
       type uint32;
       description
         "EVC MTU";
     }
     description
       "Grouping for evc mtu";
   }

   grouping mac-addr-limit-grouping {
     container mac-addr-limit {
       leaf exceeding-option {
         type uint32;
         description
           "Exceeding option";
       }
       description
         "Container of MAC-Addr limit configurations";
     }
     description
       "Grouping for mac address limit";
   }

   grouping s-vlan-grouping {
     container S-vlan {
       leaf c-vlan2evc-mapping {
         type string;
         description
           "C-VLAN to EVC mapping";
       }
       description
         "Container of S-VLAN configurations";
     }
     description
       "Grouping for s-vlan";
   }

   grouping multihoming-grouping {
     container multihoming {
       list multihoming {
         key "ESI";
         leaf ESI {
           type string;
           description
             "Ethernet segment id";
         }
         choice redundancy-mode {
           case single-active {
             leaf single-active {
               type boolean;
               description
                 "Single active";
             }
             description
               "Single active case";
           }
           case all-active {
             leaf all-active {
               type boolean;
               description
                 "All active";
             }
             description
               "All active case";
           }
           description
             "Redundancy mode choice";
         }
         description
           "List of multihomings";
       }
       description
         "Container of multihoming optional configurations";
     }
     description
       "Grouping for multihoming";
   }

   grouping l2cp-grouping {
     container L2CP-control {
       leaf stp-rstp-mstp {
         type control-mode;
         description
           "STP/RSTP/MSTP";
       }
       leaf pause {
         type control-mode;
         description
           "Pause";
       }
       leaf lacp-lamp {
         type control-mode;
         description
           "LACP/LAMP";
       }
       leaf link-oam {
         type control-mode;
         description
           "Link OAM";
       }
       leaf esmc {
         type control-mode;
         description
           "ESMC";
       }
       leaf l2cp-802.1x {
         type control-mode;
         description
           "802.x";
       }
       leaf e-lmi {
         type control-mode;
         description
           "E-LMI";
       }
       leaf lldp {
         type boolean;
         description
           "LLDP";
       }
       leaf ptp-peer-delay {
         type control-mode;
         description
           "PTP peer delay";
       }
       leaf garp-mrp {
         type control-mode;
         description
           "GARP/MARP";
       }
       leaf provider-bridge-group {
         type yang:mac-address;
         description
           "Provider bridge group reserved MAC address
            01-80-C2-00-00-08";
       }
       leaf provider-bridge-mvrp {
         type yang:mac-address;
         description
           "Provider bridge MVRP reserved MAC address
            01-80-C2-00-00-0D";
       }
       description
         "Container of L2CP control configurations";
      }
      description
        "Grouping for l2cp control";
   }

   grouping service-level-grouping {
     container service-level {
       leaf cos-identifier {
         type identityref {
           base cos-id;
         }
         description
           "COS Identifier [ EVC | EVC + PCP ]";
       }
       leaf color-identifier {
         type identityref {
           base color-id;
         }
         description
           "Color Identifier [ EVC | EVC + CVLAN ]";
       }
       leaf ingress-bw-profile-per-evc {
         type string;
         description
           "Ingress Bandwidth Profile per EVC";
       }
       leaf ingress-bw-profile-per-cos-id {
         type string;
         description
           "Ingress Bandwidth Profile per COS Identifier";
       }
       leaf egress-bw-profile-per-evc {
         type string;
         description
           "Egress Bandwidth Profile per EVC";
       }
       leaf egress-bw-profile-per-cos-id {
         type string;
         description
           "Egress Bandwidth Profile per COS Identifier";
       }
       leaf byte-offset {
         type uint16;
         description
           "For not including extra VLAN tags in the QoS
           calculation";
       }
       leaf policing {
         type identityref {
           base policing;
         }
         description
           "The policing can be either one-rate,
            two-color (1R2C) or two-rate, three-color (2R3C)";
       }
       leaf performance-tier-option {
         type identityref {
           base performance-tier-option;
         }
         description
          "Performance tier option";
       }
       leaf COS {
         type uint32;
         description
           "Class of Service";
       }
       description
       "Container of service level configurations.";
     }
     description
       "Grouping for service level.";
   }

   grouping B-U-M-strom-control-grouping {
     container B-U-M-strom-control {
       leaf BUM-overall-rate {
       type uint32;
       description
         "overall rate for BUM";
     }
     list BUM-rate-per-type {
       key "type";
       leaf type {
         type identityref {
           base BUM-type;
         }
         description
           "BUM type";
       }
       leaf rate {
         type uint32;
         description
           "Rate for BUM";
       }
       description
         "List of rate per type";
       }
       description
         "Container of B-U-M-strom-control configurations";
     }
     description
       "Grouping for B-U-M-strom-control";
   }

   grouping mac-loop-prevention-grouping {
     container mac-loop-prevention {
       leaf frequency {
         type uint32;
         description
           "Frequency";
       }
       leaf protection-type {
         type identityref {
           base loop-prevention-type;
         }
         description
           "Protection type";
       }
       leaf number-retries {
         type uint32;
         description
           "Number of retries";
       }
       description
         "Container of MAC loop prevention.";
     }
     description
       "Grouping for MAC loop prevention";
   }

   grouping ethernet-svc-oam-grouping {
     container Ethernet-Service-OAM {
       leaf MD-name {
         type string;
         description
           "Maintenance domain name";
       }
       leaf MD-level {
         type uint8;
         description
           "Maintenance domain level";
       }
       container cfm-802.1-ag {
         list n2-uni-c {
           key "MAID";
           uses cfm-802-grouping;
           description
             "List of UNI-N to UNI-C";
         }
         list n2-uni-n {
           key "MAID";
           uses cfm-802-grouping;
           description
            "List of UNI-N to UNI-N";
         }
         description
           "Container of 802.1ag CFM configurations.";
       }
       uses y-1731;
       description
         "Container for Ethernet service OAM.";
     }
     description
       "Grouping for Ethernet service OAM.";
   }

   grouping enni-management {
     container management {
       leaf site-name {
         type string;
         description
           "Site name";
       }
       leaf address {
         type inet:ip-address;
         description
           "Address";
       }
       leaf Edge-Gateway-Device-Info {
         type string;
         description
           "Edge Gateway Device Information.";
       }
       leaf type {
         type identityref {
           base management;
         }
         description
           "Management type of the connection.";
       }
       leaf management-transport {
         type identityref {
           base address-family;
         }
         description
           "Transport protocol used for management.";
       }
       description
         "Management configuration.";
     }
     description
       "Grouping for ENNI site management.";
   }

   grouping fate-sharing-group {
     container groups {
       leaf fate-sharing-group-size {
         type uint16;
         description
           "Fate sharing group size.";
       }
       list group {
         key group-id;
         leaf group-id {
           type string;
           description
             "Group-id the site network access
              is belonging to";
         }
         description
           "List of group-id";
       }
       description
         "Groups the fate sharing group member
          is belonging to";
     }
     description
       "Grouping for Fate sharing group.";
   }

   /* MAIN L2VPN SERVICE */

   container l2vpn-svc {

     /* CUSTOMER */

     container customer-info {
       uses customer-info-grouping;
       description
         "Container of customer information configurations.";
     }

     /* SERVICE */

     container vpn-services {
       list vpn-svc {
         key "svc-id";
         leaf svc-id {
           type string;
           description
             "Defining a service id.";
         }
         uses svc-type-grouping;
         container ethernet-svc-type {
           uses ethernet-service-type;
           description
             "Container of Ethernet service type";
         }
         container metro-network-id {
           uses inter-mkt-service;
           uses intra-mkt-grouping;
           description
             "Container of Metro-Network ID configurations";
         }
         container signaling-option {
           uses signaling-option-grouping;
           description
             "Container for signaling option";
         }
         container load-balance-options {
           uses load-balance-grouping;
           description
             "container for load balance options";
         }
         uses site-service;
         uses service-protection;
         description
           "List of vpn-svc";
       }
       description
         "Container of vpn-services configurations";
     }

     /* SITE */

     container site {
       container uni-sites {
         list uni-site {
           key "site-id";
           leaf site-id {
             type string;
             description
               "Container of site id";
           }
           uses site-management;
           uses customer-location-info;
           uses site-diversity;
           uses site-security;
           container signaling-option {
             if-feature signaling-option;
             uses signaling-option-grouping;
             description
               "Container for signaling option";
           }

           container load-balance-options {
             uses load-balance-grouping;
               leaf vxlan-source-port {
                 type string;
                 description
                   "Vxlan source port";
               }
             description
               "Container for load balance options";
           }

           container uni-ports {
             list uni-port {
               key "uni-id";
               leaf uni-id {
                 type string;
                 description
                   "UNI id";
               }

               uses fate-sharing-group;
               uses bearer-grouping;
               uses ethernet-connection-grouping;
               uses evc-mtu-grouping;
               uses mac-addr-limit-grouping;
               uses s-vlan-grouping;
               uses multihoming-grouping;
               uses l2cp-grouping;

               container service {
                 uses site-service;
                 uses service-level-grouping;
                 description
                   "Container for site service.";
               }

               uses B-U-M-strom-control-grouping;
               uses mac-loop-prevention-grouping;
               uses ethernet-svc-oam-grouping;
               uses site-security;

               description
                 "List of UNI ports";
             }

             description
               "Container of UNI port configurations";
           }
           description
             "List of UNI sites";
         }
         description
           "Container of UNI site configurations";
       }

       container enni-sites {
         list enni-site {
           key "site-id";
           leaf site-id {
             type string;
             description
               "Container of site id";
           }

           uses customer-location-info;
           uses site-diversity;
           uses enni-management;
           uses site-security;
           uses service-protection;

           container signaling-option {
             if-feature signaling-option;
             uses signaling-option-grouping;
             description
               "Container for signaling option";
           }

           container load-balance-options {
             uses load-balance-grouping;
               leaf vxlan-source-port {
                 type string;
                 description
                   "Vxlan source port";
               }
             description
               "Container for load balance options";
           }

           container enni-ports {
             list enni-port {
               key "enni-id";
               leaf enni-id {
                 type string;
                 description
                   "ENNI id";
               }
               leaf remote-carrier-name{
                 type string;
                    description
                      "Remote carrier name";
               }

               uses bearer-grouping;
               uses ethernet-connection-grouping;
               uses evc-mtu-grouping;
               uses mac-addr-limit-grouping;
               uses s-vlan-grouping;
               uses multihoming-grouping;
               uses l2cp-grouping;

               container service{
                 uses site-service;
                 uses service-level-grouping;
                 description
                   "Container for site service.";
               }

               uses B-U-M-strom-control-grouping;
               uses mac-loop-prevention-grouping;
               uses ethernet-svc-oam-grouping;
               uses site-security;

               description
                 "List of ENNI ports";
             }
             description
               "Container of ENNI port configurations";
           }
           description
             "List of ENNI sites";
         }
         description
           "Container of ENNI site configurations";
       }
       description
         "Container for site configurations";
     }
     description
       "Container of l2vpn-svc configurations";
   }
}
<CODE ENDS>
          
        

9. Security Considerations

The YANG modules defined in this document MAY be accessed via the RESTCONF protocol [I-D.ietf-netconf-restconf] or NETCONF protocol ([RFC6241]. The lowest RESTCONF or NETCONF layer requires that the transport-layer protocol provides both data integrity and confidentiality, see Section 2 in [I-D.ietf-netconf-restconf] and [RFC6241]. The client MUST carefully examine the certificate presented by the server to determine if it meets the client's expectations, and the server MUST authenticate client access to any protected resource. The client identity derived from the authentication mechanism used is subject to the NETCONF Access Control Module (NACM) ([RFC6536]). Other protocols to access this YANG module are also required to support the similar mechanism.

The data nodes defined in the "ietf-l2vpn-svc" YANG module MUST be carefully created/read/updated/deleted. The entries in the lists below include customer proprietary or confidential information, therefore only authorized clients MUST access the information and the other clients MUST NOT be able to access to the information.

• /l2vpn-svc/vpn-services/vpn-svc
• /l2vpn-svc/sites/uni-site
• /l2vpn-svc/sites/enni-site

10. Acknowledgements

Thanks to Qin Wu and Adrian Farrel for facilitating work on the initial revision of this document.

This document has drawn on the work of the L3SM Working Group expressed in [I-D.ietf-l3sm-l3vpn-service-model].

11. IANA Considerations

IANA is requested to assign a new URI from the IETF XML registry ([RFC3688]). The following URI is suggested:

          

    URI: urn:ietf:params:xml:ns:yang:ietf-l2vpn-svc
    Registrant Contact: L2SM WG
    XML: N/A, the requested URI is an XML namespace

           
         

This document also requests a new YANG module name in the YANG Module Names registry ([RFC6020]) with the following suggestion:

          

    name: ietf-l2vpn-svc
    namespace: urn:ietf:params:xml:ns:yang:ietf-l2vpn-svc
    prefix: l2vpn-svc
    reference: RFC XXXX

           
         

12. References

12.1. Normative References

[I-D.ietf-netconf-restconf]	Bierman, A., Bjorklund, M. and K. Watsen, "RESTCONF Protocol", Internet-Draft draft-ietf-netconf-restconf-17, September 2016.
[RFC2119]	Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997.
[RFC3688]	Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, DOI 10.17487/RFC3688, January 2004.
[RFC4448]	Martini, L., Rosen, E., El-Aawar, N. and G. Heron, "Encapsulation Methods for Transport of Ethernet over MPLS Networks", RFC 4448, DOI 10.17487/RFC4448, April 2006.
[RFC4761]	Kompella, K. and Y. Rekhter, "Virtual Private LAN Service (VPLS) Using BGP for Auto-Discovery and Signaling", RFC 4761, DOI 10.17487/RFC4761, January 2007.
[RFC4762]	Lasserre, M. and V. Kompella, "Virtual Private LAN Service (VPLS) Using Label Distribution Protocol (LDP) Signaling", RFC 4762, DOI 10.17487/RFC4762, January 2007.
[RFC6020]	Bjorklund, M., "YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, DOI 10.17487/RFC6020, October 2010.
[RFC6241]	Enns, R., Bjorklund, M., Schoenwaelder, J. and A. Bierman, "Network Configuration Protocol (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011.
[RFC6536]	Bierman, A. and M. Bjorklund, "Network Configuration Protocol (NETCONF) Access Control Model", RFC 6536, DOI 10.17487/RFC6536, March 2012.
[RFC7432]	Sajassi, A., Aggarwal, R., Bitar, N., Isaac, A., Uttaro, J., Drake, J. and W. Henderickx, "BGP MPLS-Based Ethernet VPN", RFC 7432, DOI 10.17487/RFC7432, February 2015.

12.2. Informative References

[I-D.ietf-bess-evpn-yang]	Brissette, P., Sajassi, A., Shah, H., Li, Z., Tiruveedhula, K., Hussain, I. and J. Rabadan, "Yang Data Model for EVPN", Internet-Draft draft-ietf-bess-evpn-yang-01, July 2016.
[I-D.ietf-bess-l2vpn-yang]	Shah, H., Brissette, P., Chen, I., Hussain, I. and B. Wen, "YANG Data Model for MPLS-based L2VPN", Internet-Draft draft-ietf-bess-l2vpn-yang-00, June 2016.
[I-D.ietf-l3sm-l3vpn-service-model]	Litkowski, S., Tomotaki, L. and K. Ogaki, "YANG Data Model for L3VPN service delivery", Internet-Draft draft-ietf-l3sm-l3vpn-service-model-16, September 2016.
[I-D.wu-opsawg-service-model-explained]	Wu, Q., LIU, S. and A. Farrel, "Service Models Explained", Internet-Draft draft-wu-opsawg-service-model-explained-03, September 2016.
[IEEE-802-1ag]	IEEE, "802.1ag - Connectivity Fault Management", December 2007.
[ITU-T-Y-1731]	ITU-T, "Recommendation Y.1731 - OAM functions and mechanisms for Ethernet based networks", February 2008.
[MEF-23-1]	MEF Forum, "Implementation Agreement MEF 23.1 : Carrier Ethernet Class of Service - Phase 2", January 2012.
[RFC6624]	Kompella, K., Kothari, B. and R. Cherukuri, "Layer 2 Virtual Private Networks Using BGP for Auto-Discovery and Signaling", RFC 6624, DOI 10.17487/RFC6624, May 2012.

Authors' Addresses