Internet DRAFT - draft-tissa-lime-yang-oam-model
draft-tissa-lime-yang-oam-model
Network Working Group T. Senevirathne
Internet-Draft N. Finn
Intended status: Standards Track D. Kumar, Ed.
Expires: February 5, 2016 S. Salam
Cisco
Q. Wu, Ed.
M. Wang
Huawei
August 4, 2015
Generic YANG Data Model for Operations, Administration, and Maintenance
(OAM)
draft-tissa-lime-yang-oam-model-06
Abstract
This document presents base YANG Data model for OAM. It provides a
protocol-independent and technology-independent abstraction of key
OAM constructs. Based model presented here can be extended to
include technology specific details. This is leading to uniformity
between OAM technologies and support nested OAM workflows (i.e.,
performing OAM functions at different layers through a unified
interface).
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on February 5, 2016.
Copyright Notice
Copyright (c) 2015 IETF Trust and the persons identified as the
document authors. All rights reserved.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions used in this document . . . . . . . . . . . . . . 4
2.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 5
3. Architecture of Generic YANG Model for OAM . . . . . . . . . 6
4. Overview of the OAM Model . . . . . . . . . . . . . . . . . . 7
4.1. Maintenance Domain (MD) configuration . . . . . . . . . . 8
4.2. Maintenance Association (MA) configuration . . . . . . . 8
4.3. Maintenance Endpoint (MEP) configuration . . . . . . . . 9
4.4. rpc definitions . . . . . . . . . . . . . . . . . . . . . 9
4.5. OAM data hierarchy . . . . . . . . . . . . . . . . . . . 12
5. OAM YANG Module . . . . . . . . . . . . . . . . . . . . . . . 17
6. Base Mode . . . . . . . . . . . . . . . . . . . . . . . . . . 41
6.1. MEP Address . . . . . . . . . . . . . . . . . . . . . . . 41
6.2. MEP ID for Base Mode . . . . . . . . . . . . . . . . . . 42
6.3. Maintenance Domain . . . . . . . . . . . . . . . . . . . 42
6.4. Maintenance Association . . . . . . . . . . . . . . . . . 42
7. Note . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
8. Security Considerations . . . . . . . . . . . . . . . . . . . 43
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 43
10. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 44
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 44
11.1. Normative References . . . . . . . . . . . . . . . . . . 44
11.2. Informative References . . . . . . . . . . . . . . . . . 45
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 46
1. Introduction
Operations, Administration, and Maintenance (OAM) are important
networking functions that allow operators to:
1. Monitor networks connections (Connectivity Verification,
Continuity Check).
2. Troubleshoot failures (Fault verification and localization).
3. Monitor Performance
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An overview of OAM tools is presented at [RFC7276].
Ping and Traceroute [RFC792], [RFC4443] are well-known fault
verification and isolation tools, respectively, for IP networks.
Over the years, different technologies have developed similar tools
for similar purposes.
[IEEE802.1Q] Connectivity Fault Management is a well-established OAM
standard that is widely adopted for Ethernet networks. ITU-T
[Y.1731][Y.1731], MEF Service OAM, MPLS-TP [RFC6371], TRILL
[RFC7455][RFC7455] all define OAM methods based on manageability
frame work of [IEEE802.1Q] [IEEE802.1Q]CFM.
Given the wide adoption of the underlying OAM concepts defined in
[IEEE802.1Q][IEEE802.1Q] CFM, it is a reasonable choice to develop
the unified management framework based on those concepts. In this
document, we take the [IEEE802.1Q][IEEE802.1Q] CFM model and extend
it to a technology independent framework and build the corresponding
YANG model accordingly. The YANG model presented in this document is
the base model and supports generic continuity check, connectivity
verification and path discovery. The generic YANG model for OAM is
designed such that it can be extended to cover various technologies.
Technology dependent nodes and RPC (remote process call) commands are
defined in technology specific YANG models, which use and extend the
base model defined here. As an example, VXLAN uses source UDP port
number for flow entropy, while MPLS [RFC4379] uses IP addresses or
the label stack for flow entropy in the hashing for multipath
selection. To capture this variation, corresponding YANG models
would define the applicable structures as augmentation to the generic
base model presented here. This accomplishes three purposes: first
it keeps each YANG model smaller and manageable. Second, it allows
independent development of corresponding YANG models. Third,
implementations can limit support to only the applicable set of YANG
models. (e.g. TRILL RBridge may only need to implement Generic model
and the TRILL YANG model).
All implementations that follow the YANG framework presented in this
document MUST implement the generic YANG model presented here.
The YANG data model presented in this document is generated at the
management layer. Encapsulations and state machines may differ
according to each OAM protocol. A user who wishes to issues a Ping
command or a Traceroute or initiate a performance monitoring session
can do so in the same manner regardless of the underlying protocol or
technology or specific vendor implementation.
As an example, consider a scenario where an IP ping from device A to
Device B failed. Between device A and B there are IEEE 802.1 bridges
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a,b and c. Let's assume a,b and c are using [IEEE802.1Q] CFM. A
user upon detecting the IP layer ping failures may decide to drill
down to the Ethernet layer and issue the corresponding fault
verification (LBM) and fault isolation (LTM) tools, using the same
API. This ability to go down to the same portion of path atlower
layer for Fault localization and troubleshooting is referred to as
"nested OAM workflow" and is a useful concept that leads to efficient
network troubleshooting and maintenance. The OAM YANG model
presented in this document facilitates that without needing changes
to the underlying protocols.
2. Conventions used in this document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
The following notations are used within the data tree and carry the
meaning as below.
Each node is printed as:
<status> <flags> <name> <opts> <type>
<status> is one of:
+ for current
x for deprecated
o for obsolete
<flags> is one of:
rw for configuration data
ro for non-configuration data
-x for rpcs
-n for notifications
<name> is the name of the node
If the node is augmented into the tree from another module, its name
is printed as <prefix>:<name>.
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<opts> is one of:
? for an optional leaf or choice
! for a presence container
* for a leaf-list or list
[<keys>] for a list's keys
<type> is the name of the type for leafs and leaf-lists
In this document, these words will appear with that interpretation
only when in ALL CAPS. Lower case uses of these words are not to be
interpreted as carrying RFC-2119 significance.
2.1. Terminology
CCM - Continuity Check Message [IEEE802.1Q].
ECMP - Equal Cost Multipath.
LBM - Loopback Message [IEEE802.1Q].
MP - Maintenance Point [IEEE802.1Q].
MEP - Maintenance End Point [RFC7174] [IEEE802.1Q] [RFC6371].
MIP - Maintenance Intermediate Point [RFC7174] [IEEE802.1Q]
[RFC6371].
MA - Maintenance Association [IEEE802.1Q] [RFC7174].
MD - Maintenance Domain [IEEE802.1Q]
MTV - Multi-destination Tree Verification Message.
OAM - Operations, Administration, and Maintenance [RFC6291].
TRILL - Transparent Interconnection of Lots of Links [RFC6325].
CFM - Connectivity Fault Management [RFC7174] [IEEE802.1Q].
RPC - Remote Process Call.
CC - Continuity Check [RFC7276]. Continuity Checks are used to
verify that a destination is reachable and therefore also
referred to as reachability verification.
CV - Connectivity Verification [RFC7276].Connectivity
Verifications are also referred to as path verification and
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used to verify not only that the two MPs are connected, but
also that they are connected through the expected path,
allowing detection of unexpected topology changes.
3. Architecture of Generic YANG Model for OAM
In this document we define a generic YANG model for OAM. The YANG
model defined here is generic such that other technologies can extend
it for technology specific needs. The Generic YANG model acts as the
root for other OAM YANG models. This allows users to traverse
between OAM of different technologies at ease through a uniform API
set. This is also provides a nested OAM workflow. Figure 1 depicts
the relationship of different OAM YANG models to the Generic YANG
Model for OAM. Some technologies may have different sub-
technologies. As an example, consider Network Virtualization
Overlays. These could employ either VXLAN or NVGRE as encapsulation.
The Generic YANG model for OAM provides a framework where technology-
specific YANG models can inherit constructs from the base YANG models
without needing to redefine them within the sub-technology.
Figure 1 depicts relationship of different YANG modules.
+-+-+-+-+-+
| gen |
|OAM YANG |
+-+-+-+-+-+
|
O
|
+---------------------------------------------------------+
| | | | |
+-+-+-+-+-+ +-+-+-+-+-+ +-+-+-+-+-+ +-+-+-+-+-+ +-+-+-+-+-+
| TRILL | | NVO3 | | MPLS | | IP | . . .| foo |
|OAM YANG | |OAM YANG | |OAM YANG | |OAM YANG | |OAM YANG |
+-+-+-+-+-+ +-+-+-+-+-+ +-+-+-+-+-+ +-+-+-+-+-+ +-+-+-+-+-+
| | | | |
| +-+-+-+-+-+ +-+-+-+-+-+ | +-+-+-+-+-+
| | NVO3 | | MPLS | | . . .| foo |
| |sub tech | |sub tech | | |sub tech |
| +-+-+-+-+-+ +-+-+-+-+-+ | +-+-+-+-+-+
| | | | |
| | | | |
+------------------------------------------------------------+
| Uniform API |
+------------------------------------------------------------+
Relationship of OAM YANG model to generic (base) YANG model
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4. Overview of the OAM Model
In this document we adopt the concepts of the [IEEE802.1Q] CFM model
and structure it such that it can be adapted to different
technologies.
At the top of the Model is the Maintenance Domain. Each Maintenance
Domain is associated with a Maintenance Name and a Domain Level.
Under each Maintenance Domain there is one or more Maintenance
Association (MA). In IP, the MA can be per IP Subnet, in NVO3 this
can be per VNI and for TRILL this can be per Fine-Grained Label or
for VPLS this can be per VPLS instance.
Under each MA, there can be two or more MEPs (Maintenance Association
End Points). MEPs are addressed by their respective technology
specific address identifiers. The YANG model presented here provides
flexibility to accommodate different addressing schemes.
In the vertical direction orthogonal to the Maintenance Domain,
presented are the commands. Those, in YANG terms, are the rpc
commands. These rpc commands provide uniform APIs for continuity
check,connectivity verification, path discovery and their equivalents
as well as other OAM commands.
The generic YANG model defined here does not require explicit
configuration of OAM entities prior to using any of the OAM tools.The
OAM tools used here are limited to OAM toolset specified in section
5.1 of [RFC7276]. Users of Ping and Traceroute tools within IP
devices are expecting ability to use OAM tools with no explicit
configuration. In order to facilitate zero- touch experience, this
document defines a default mode of OAM. The default mode of OAM is
referred to as the Base Mode and specifies default values for each of
model parameters, such as Maintenance Domain Level, Name of the
Maintenance Association and Addresses of MEP and so on. The default
values of these depend on the technology. Base Mode for TRILL is
defined in [RFC7455]. Base mode for other technologies such as NVO3,
MPLS and future extensions will be defined in their corresponding
documents.
It is important to note that, no specific enhancements are needed in
the YANG model to support Base Mode. Implementations that comply
with this document, by default implement the data nodes of the
applicable technology. Data nodes of the Base Mode are read-only
nodes.
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4.1. Maintenance Domain (MD) configuration
The container "domains" is the top level container within the gen-oam
module. Within the container "domains", separate list is maintained
per MD. The MD list uses the key MD-name-string for indexing. MD-
name-string is a leaf and derived from type string. Additional name
formats as defined in [IEEE802.1Q] or other standards can be included
by association of the MD-name-format with an identity-ref. MD-name-
format indicates the format of the augmented MD-names. MD-name is
presented as choice/case construct. Thus, it is easily augmentable
by derivative work.
module: ietf-gen-oam
+--rw domains
+--rw domain* [technology MD-name-string]
+--rw technology identityref
+--rw MD-name-string MD-name-string
+--rw MD-name-format? identityref
+--rw (MD-name)?
| +--:(MD-name-null)
| +--rw MD-name-null? empty
+--rw md-level MD-level .
Snippet of data hierarchy related to OAM domains
4.2. Maintenance Association (MA) configuration
Within a given Maintenance Domain there can be one or more
Maintenance Associations (MA). MAs are represented as a list and
indexed by the MA-name-string. Similar to MD-name defined
previously, additional name formats can be added by augmenting the
name-format identity-ref and adding applicable case statements to MA-
name.
module: ietf-gen-oam
+--rw domains
+--rw domain* [technology MD-name-string]
.
.
+--rw MAs
+--rw MA* [MA-name-string]
+--rw MA-name-string MA-name-string
+--rw MA-name-format? identityref
+--rw (MA-name)?
| +--:(MA-name-null)
| +--rw MA-name-null? empty
Snippet of data hierarchy related to Maintenance Associations (MA)
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4.3. Maintenance Endpoint (MEP) configuration
Within a given Maintenance Association (MA), there can be one or more
Maintenance End Points (MEP). MEPs are represented as a list within
the data hierarchy and indexed by the key MEP-name.
module: ietf-gen-oam
+--rw domains
+--rw domain* [technology MD-name-string]
+--rw technology identityref
.
.
+--rw MAs
+--rw MA* [MA-name-string]
+--rw MA-name-string MA-name-string
.
.
+--rw MEP* [mep-name]
| +--rw mep-name MEP-name
| +--rw (MEP-ID)?
| | +--:(MEP-ID-int)
| | +--rw MEP-ID-int? int32
| | +--:(MEP-ID-tlv)
| | +--rw MEP-ID-type? int16
| | +--rw MEP-ID-len? int16
| | +--rw MEP-ID-value? binary
| +--rw MEP-ID-format? identityref
| +--rw (mp-address)?
| | +--:(mac-address)
| | | +--rw mac-address? yang:mac-address
| | +--:(ipv4-address)
| | | +--rw ipv4-address? inet:ipv4-address
| | +--:(ipv6-address)
| | +--rw ipv6-address? inet:ipv6-address
. .
. .
. .
Snippet of data hierarchy related to Maintenance Endpoint (MEP)
4.4. rpc definitions
The rpc model facilitates issuing commands to a NETCONF server (in
this case to the device that need to execute the OAM command) and
obtain a response. rpc model defined here abstracts OAM specific
commands in a technology independent manner.
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There are several rpc commands defined for the purpose of OAM. In
this section we present a snippet of the continuity check command for
illustration purposes. Please refer to Section 4 for the complete
data hierarchy and Section 5 for the YANG model.
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module: ietf-gen-oam
+--rw domains
+--rw domain* [technology MD-name-string]
+--rw technology identityref
.
.
rpcs:
+---x continuity-check
| +--ro input
| | +--ro technology identityref
| | +--ro MD-name-string MD-name-string
| | +--ro MA-name-string? MA-name-string
| | +--ro (flow-entropy)?
| | | +--:(flow-entropy-null)
| | | +--ro flow-entropy-null? empty
| | +--ro priority? uint8
| | +--ro ttl? uint8
| | +--ro session-type enumeration
| | +--ro ecmp-choice? ecmp-choices
| | +--ro sub-type? identityref
| | +--ro outgoing-interfaces* [interface]
| | | +--ro interface if:interface-ref
| | +--ro source-mep? MEP-name
| | +--ro destination-mp
| | | +--ro (mp-address)?
| | | | +--:(mac-address)
| | | | | +--ro mac-address? yang:mac-address
| | | | +--:(ipv4-address)
| | | | | +--ro ipv4-address? inet:ipv4-address
| | | | +--:(ipv6-address)
| | | | +--ro ipv6-address? inet:ipv6-address
| | | +--ro (MEP-ID)?
| | | | +--:(MEP-ID-int)
| | | | +--ro MEP-ID-int? int32
| | | +--ro MEP-ID-format? identityref
| | +--ro count? uint32
| | +--ro interval? Interval
| | +--ro packet-size? uint32
| +--ro output
| +--ro tx-packt-count? oam-counter32
| +--ro rx-packet-count? oam-counter32
| +--ro min-delay? oam-counter32
| +--ro average-delay? oam-counter32
| +--ro max-delay? oam-counter32
Snippet of data hierarchy related to rpc call continuity-check
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4.5. OAM data hierarchy
The complete data hierarchy related to the OAM YANG model is
presented below.
module: ietf-gen-oam
+--rw domains
+--rw domain* [technology MD-name-string]
+--rw technology identityref
+--rw MD-name-string MD-name-string
+--rw MD-name-format? identityref
+--rw (MD-name)?
| +--:(MD-name-null)
| +--rw MD-name-null? empty
+--rw md-level? MD-level
+--rw MAs
+--rw MA* [MA-name-string]
+--rw MA-name-string MA-name-string
+--rw MA-name-format? identityref
+--rw (MA-name)?
| +--:(MA-name-null)
| +--rw MA-name-null? empty
+--rw (connectivity-context)?
| +--:(context-null)
| +--rw context-null? empty
+--rw mep-direction MEP-direction
+--rw interval? Interval
+--rw loss-threshold? uint32
+--rw ttl? uint8
+--rw (flow-entropy)?
| +--:(flow-entropy-null)
| +--rw flow-entropy-null? empty
+--rw priority? uint8
+--rw MEP* [mep-name]
| +--rw mep-name MEP-name
| +--rw (MEP-ID)?
| | +--:(MEP-ID-int)
| | | +--rw MEP-ID-int? int32
| | +--:(MEP-ID-tlv)
| | +--rw MEP-ID-type? int16
| | +--rw MEP-ID-len? int16
| | +--rw MEP-ID-value? binary
| +--rw MEP-ID-format? identityref
| +--rw (mp-address)?
| | +--:(mac-address)
| | | +--rw mac-address? yang:mac-address
| | +--:(ipv4-address)
| | | +--rw ipv4-address? inet:ipv4-address
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| | +--:(ipv6-address)
| | +--rw ipv6-address? inet:ipv6-address
| +--rw (connectivity-context)?
| | +--:(context-null)
| | +--rw context-null? empty
| +--rw Interface? if:interface-ref
| +--rw (topology)?
| | +--:(topo-null)
| | +--rw topo-null? empty
| +--ro admin-status? leafref
| +--ro oper-status? leafref
| +--rw (flow-entropy)?
| | +--:(flow-entropy-null)
| | +--rw flow-entropy-null? empty
| +--rw priority? uint8
| +--rw session* [session-cookie]
| +--rw session-cookie uint32
| +--rw ttl? uint8
| +--rw interval? Interval
| +--rw enable? boolean
| +--rw ecmp-choice? ecmp-choices
| +--rw source-mep? MEP-name
| +--rw destination-mep
| | +--rw (MEP-ID)?
| | | +--:(MEP-ID-int)
| | | | +--rw MEP-ID-int? int32
| | | +--:(MEP-ID-tlv)
| | | +--rw MEP-ID-type? int16
| | | +--rw MEP-ID-len? int16
| | | +--rw MEP-ID-value? binary
| | +--rw MEP-ID-format? identityref
| +--rw destination-mep-address
| | +--rw (mp-address)?
| | +--:(mac-address)
| | | +--rw mac-address? yang:mac-address
| | +--:(ipv4-address)
| | | +--rw ipv4-address? inet:ipv4-address
| | +--:(ipv6-address)
| | +--rw ipv6-address? inet:ipv6-address
| +--rw (connectivity-context)?
| | +--:(context-null)
| | +--rw context-null? empty
| +--rw (flow-entropy)?
| | +--:(flow-entropy-null)
| | +--rw flow-entropy-null? empty
| +--rw priority? uint8
| +--rw outgoing-interface* [interface]
| +--rw interface leafref
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+--rw MIP* [interface]
| +--rw interface if:interface-ref
+--rw related-oam-layer* [offset]
+--rw offset int32
+--rw technology identityref
+--rw MD-name-string MD-name-string
+--rw MA-name-string? MA-name-string
rpcs:
+---x continuity-check
| +--ro input
| | +--ro technology identityref
| | +--ro MD-name-string MD-name-string
| | +--ro MA-name-string? MA-name-string
| | +--ro (flow-entropy)?
| | | +--:(flow-entropy-null)
| | | +--ro flow-entropy-null? empty
| | +--ro priority? uint8
| | +--ro ttl? uint8
| | +--ro session-type-enum? enumeration
| | +--ro ecmp-choice? ecmp-choices
| | +--ro sub-type? identityref
| | +--ro outgoing-interfaces* [interface]
| | | +--ro interface if:interface-ref
| | +--ro source-mep? MEP-name
| | +--ro destination-mp
| | | +--ro (mp-address)?
| | | | +--:(mac-address)
| | | | | +--ro mac-address? yang:mac-address
| | | | +--:(ipv4-address)
| | | | | +--ro ipv4-address? inet:ipv4-address
| | | | +--:(ipv6-address)
| | | | +--ro ipv6-address? inet:ipv6-address
| | | +--ro (MEP-ID)?
| | | | +--:(MEP-ID-int)
| | | | | +--ro MEP-ID-int? int32
| | | | +--:(MEP-ID-tlv)
| | | | +--ro MEP-ID-type? int16
| | | | +--ro MEP-ID-len? int16
| | | | +--ro MEP-ID-value? binary
| | | +--ro MEP-ID-format? identityref
| | +--ro count? uint32
| | +--ro interval? Interval
| | +--ro packet-size? uint32
| +--ro output
| +--ro tx-packt-count? oam-counter32
| +--ro rx-packet-count? oam-counter32
| +--ro min-delay? oam-counter32
| +--ro average-delay? oam-counter32
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| +--ro max-delay? oam-counter32
+---x continuity-verification {connectivity-verification}?
| +--ro input
| | +--ro technology identityref
| | +--ro MD-name-string MD-name-string
| | +--ro MA-name-string? MA-name-string
| | +--ro (flow-entropy)?
| | | +--:(flow-entropy-null)
| | | +--ro flow-entropy-null? empty
| | +--ro priority? uint8
| | +--ro ttl? uint8
| | +--ro session-type-enum? enumeration
| | +--ro ecmp-choice? ecmp-choices
| | +--ro sub-type? identityref
| | +--ro outgoing-interfaces* [interface]
| | | +--ro interface if:interface-ref
| | +--ro source-mep? MEP-name
| | +--ro destination-mp
| | | +--ro (mp-address)?
| | | | +--:(mac-address)
| | | | | +--ro mac-address? yang:mac-address
| | | | +--:(ipv4-address)
| | | | | +--ro ipv4-address? inet:ipv4-address
| | | | +--:(ipv6-address)
| | | | +--ro ipv6-address? inet:ipv6-address
| | | +--ro (MEP-ID)?
| | | | +--:(MEP-ID-int)
| | | | | +--ro MEP-ID-int? int32
| | | | +--:(MEP-ID-tlv)
| | | | +--ro MEP-ID-type? int16
| | | | +--ro MEP-ID-len? int16
| | | | +--ro MEP-ID-value? binary
| | | +--ro MEP-ID-format? identityref
| | +--ro count? uint32
| | +--ro interval? Interval
| | +--ro packet-size? uint32
| +--ro output
| +--ro tx-packt-count? oam-counter32
| +--ro rx-packet-count? oam-counter32
| +--ro min-delay? oam-counter32
| +--ro average-delay? oam-counter32
| +--ro max-delay? oam-counter32
+---x path-discovery
+--ro input
| +--ro technology identityref
| +--ro MD-name-string MD-name-string
| +--ro MA-name-string? MA-name-string
| +--ro (flow-entropy)?
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| | +--:(flow-entropy-null)
| | +--ro flow-entropy-null? empty
| +--ro priority? uint8
| +--ro ttl? uint8
| +--ro session-type-enum? enumeration
| +--ro command-sub-type? identityref
| +--ro ecmp-choice? ecmp-choices
| +--ro outgoing-interfaces* [interface]
| | +--ro interface if:interface-ref
| +--ro source-mep? MEP-name
| +--ro destination-mp
| | +--ro (mp-address)?
| | | +--:(mac-address)
| | | | +--ro mac-address? yang:mac-address
| | | +--:(ipv4-address)
| | | | +--ro ipv4-address? inet:ipv4-address
| | | +--:(ipv6-address)
| | | +--ro ipv6-address? inet:ipv6-address
| | +--ro (MEP-ID)?
| | | +--:(MEP-ID-int)
| | | | +--ro MEP-ID-int? int32
| | | +--:(MEP-ID-tlv)
| | | +--ro MEP-ID-type? int16
| | | +--ro MEP-ID-len? int16
| | | +--ro MEP-ID-value? binary
| | +--ro MEP-ID-format? identityref
| +--ro count? uint32
| +--ro interval? Interval
+--ro output
+--ro response* [response-index]
+--ro response-index uint8
+--ro ttl? uint8
+--ro destination-mp
| +--ro (mp-address)?
| | +--:(mac-address)
| | | +--ro mac-address? yang:mac-address
| | +--:(ipv4-address)
| | | +--ro ipv4-address? inet:ipv4-address
| | +--:(ipv6-address)
| | +--ro ipv6-address? inet:ipv6-address
| +--ro (MEP-ID)?
| | +--:(MEP-ID-int)
| | | +--ro MEP-ID-int? int32
| | +--:(MEP-ID-tlv)
| | +--ro MEP-ID-type? int16
| | +--ro MEP-ID-len? int16
| | +--ro MEP-ID-value? binary
| +--ro MEP-ID-format? identityref
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+--ro tx-packt-count? oam-counter32
+--ro rx-packet-count? oam-counter32
+--ro min-delay? oam-counter32
+--ro average-delay? oam-counter32
+--ro max-delay? oam-counter32
notifications:
+---n defect-condition-notification
+--ro technology identityref
+--ro MD-name-string MD-name-string
+--ro MA-name-string? MA-name-string
+--ro mep-name? MEP-name
+--ro defect-type? identityref
+--ro generating-mepid
| +--ro (MEP-ID)?
| | +--:(MEP-ID-int)
| | | +--ro MEP-ID-int? int32
| | +--:(MEP-ID-tlv)
| | +--ro MEP-ID-type? int16
| | +--ro MEP-ID-len? int16
| | +--ro MEP-ID-value? binary
| +--ro MEP-ID-format? identityref
+--ro (error)?
+--:(error-null)
| +--ro error-null? empty
+--:(error-code)
+--ro error-code? int3
+--ro error-code? int32
data hierarchy of OAM
5. OAM YANG Module
<CODE BEGINS> file "ietf-gen-oam.yang"
module ietf-gen-oam {
namespace "urn:ietf:params:xml:ns:yang:ietf-gen-oam";
prefix goam;
import ietf-interfaces {
prefix if;
}
import ietf-yang-types {
prefix yang;
}
import ietf-inet-types {
prefix inet;
}
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organization "IETF LIME Working Group";
contact
"Tissa Senevirathne tsenevir@cisco.com";
description
"This YANG module defines the generic configuration,
statistics and rpc for OAM to be used within IETF in
a protocol indpendent manner. Functional level
abstraction is indendent with YANG modeling. It is
assumed that each protocol maps corresponding
abstracts to its native format.
Each protocol may extend the YANG model defined
here to include protocol specific extensions";
revision 2015-04-09 {
description
"Initial revision. - 04 version";
reference "draft-tissa-lime-oam";
}
/* features */
feature connectivity-verification {
description
"This feature indicates that the server supports
executing connectivity verification OAM command and
returning a response. Servers that do not advertise
this feature will not support executing
connectivity verification command or rpc model for
connectivity verification command.";
}
/* Identities */
identity technology-types {
description
"this is the base identy of technology types which are
vpls, nvo3, TRILL, ipv4, ipv6, mpls, etc";
}
identity ipv4 {
base technology-types;
description
"technology of ipv4";
}
identity ipv6 {
base technology-types;
description
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"technology of ipv6";
}
identity command-sub-type {
description
"defines different rpc command subtypes, e.g rfc792 IP
ping, rfc4379 LSP ping, rfc6905 trill OAM, this is
optional for most cases";
}
identity icmp-rfc792 {
base command-sub-type;
description
"Defines the command subtypes for ICMP ping";
reference "RFC 792";
}
identity name-format {
description
"This defines the name format, IEEE 8021Q CFM defines varying
styles of names. It is expected name format as an identity ref
to be extended with new types.";
}
identity name-format-null {
base name-format;
description
"defines name format as null";
}
identity identifier-format {
description
"identifier-format identity can be augmented to define other
format identifiers used in MEPD-ID etc";
}
identity identifier-format-integer {
base identifier-format;
description
"defines identifier-format to be integer";
}
identity defect-types {
description
"defines different defect types, e.g. remote rdi,
mis-connection defect, loss of continuity";
}
identity remote-rdi {
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base defect-types;
description
" Indicates the aggregate health of the remote MEPs. ";
}
identity remote-mep-error{
base defect-types;
description
" Indicates that one or more of the remote MEPs is
reporting a failure ";
}
identity invalue-oam-error{
base defect-types;
description
"Indicates that one or more invalid OAM messages has been
received and that 3.5 times that OAM message transmission
interval has not yet expired.
";
}
identity cross-connect-error{
base defect-types;
description
" Indicates that one or more cross-connect oam messages has been
received and that 3.5 times that OAM message transmission
interval has not yet expired.
";
}
/* typedefs */
typedef MEP-direction {
type enumeration {
enum "Up" {
value 0;
description
"Indicates when OAM frames are transmitted towards and
received from the bridging/routing function.";
}
enum "Down" {
value 1;
description
"Indicates when OAM frames are transmitted towards and
received from the wire.";
}
}
description
"MEP direction.";
}
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typedef MEP-name {
type string;
description
"Generic administrative name for a MEP";
}
typedef Interval {
type uint32;
units "milliseconds";
default "1000";
description
"Interval between packets in milliseconds.
0 means no packets are sent.";
}
typedef ecmp-choices {
type enumeration {
enum "ecmp-use-platform-hash" {
value 0;
description
"Use Platform hashing.";
}
enum "ecmp-use-round-robin" {
value 1;
description
"Use round robin hashing.";
}
}
description
"Equal cost multi Path Choices";
}
typedef MD-name-string {
type string;
default "";
description
"Generic administrative name for an MD";
}
typedef MA-name-string {
type string;
default "";
description
"Generic administrative name for an MA";
}
typedef oam-counter32 {
type yang:zero-based-counter32;
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description
"defines 32 bit counter for OAM";
}
typedef MD-level {
type uint32 {
range "0..255";
}
description
"Maintenance Domain level. The level may be restricted in
certain protocols (eg to 0-7)";
}
/* groupings */
grouping topology {
choice topology {
case topo-null {
description
"this is a placeholder when no topology is needed";
leaf topo-null {
type empty;
description
"there is no topology define, it will be defined
in technology specific model.";
}
}
description
"Topology choices";
}
description
"Topology";
}
grouping error-message {
choice error {
case error-null {
description
"this is a placeholder when no error status is needed";
leaf error-null {
type empty;
description
"there is no error define, it will be defined in
technology specific model.";
}
}
case error-code {
description
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"this is a placeholder to display error code.";
leaf error-code {
type int32;
description
"error code is integer value specific to technology.";
}
}
description
"Error Message choices.";
}
description
"Error Message.";
}
grouping mp-address {
choice mp-address {
case mac-address {
leaf mac-address {
type yang:mac-address;
description
"MAC Address";
}
description
"MAC Address based MP Addressing.";
}
case ipv4-address {
leaf ipv4-address {
type inet:ipv4-address;
description
"Ipv4 Address";
}
description
"Ip Address based MP Addressing.";
}
case ipv6-address {
leaf ipv6-address {
type inet:ipv6-address;
description
"Ipv6 Address";
}
description
"ipv6 Address based MP Addressing.";
}
description
"MP Addressing.";
}
description
"MP Address";
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}
grouping maintenance-domain-id {
description
"Grouping containing leaves sufficient to identify an MD";
leaf technology {
type identityref {
base technology-types;
}
mandatory true;
description
"Defines the technology";
}
leaf MD-name-string {
type MD-name-string;
mandatory true;
description
"Defines the generic administrative maintenance domain name";
}
}
grouping MD-name {
leaf MD-name-format {
type identityref {
base name-format;
}
description
"Name format.";
}
choice MD-name {
case MD-name-null {
leaf MD-name-null {
when "../../../MD-name-format = name-format-null" {
description
"MD name format is equal to null format.";
}
type empty;
description
"MD name Null.";
}
}
description
"MD name.";
}
description
"MD name";
}
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grouping ma-identifier {
description
"Grouping containing leaves sufficient to identify an MA";
leaf MA-name-string {
type MA-name-string;
description
"MA name string.";
}
}
grouping MA-name {
description
"MA name";
leaf MA-name-format {
type identityref {
base name-format;
}
description
"Ma name format";
}
choice MA-name {
case MA-name-null {
leaf MA-name-null {
when "../../../MA-name-format = name-format-null" {
description
"MA";
}
type empty;
description
"empty";
}
}
description
"MA name";
}
}
grouping MEP-ID {
choice MEP-ID {
default "MEP-ID-int";
case MEP-ID-int {
leaf MEP-ID-int {
type int32;
description
"MEP ID in integer format";
}
}
case MEP-ID-tlv {
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leaf MEP-ID-type {
type int16;
description
"Type of MEP-ID";
}
leaf MEP-ID-len {
type int16;
description
"Length of MEP-ID value";
}
leaf MEP-ID-value {
type binary {
length "12..255";
}
description
"Value please refer RFC6428.";
}
}
description
"MEP-ID";
}
leaf MEP-ID-format {
type identityref {
base identifier-format;
}
description
"MEP ID format.";
}
description
"MEP-ID";
}
grouping MEP {
description
"Defines elements within the MEP";
leaf mep-name {
type MEP-name;
mandatory true;
description
"Generic administrative name of the MEP";
}
uses MEP-ID;
uses mp-address;
uses connectivity-context;
leaf Interface {
type if:interface-ref;
description
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"Interface name as defined by ietf-interfaces";
}
uses topology;
}
grouping session-type {
description
"This object indicates the current session
definition.";
leaf session-type-enum {
type enumeration {
enum proactive {
description
"The current session is proactive";
}
enum on-demand {
description
"The current session is on-demand.";
}
}
description
"session type enum";
}
}
grouping monitor-stats {
leaf tx-packt-count {
type oam-counter32;
description
"Transmitted Packet count";
}
leaf rx-packet-count {
type oam-counter32;
description
"Received packet count";
}
leaf min-delay {
type oam-counter32;
units milliseconds;
description
"Delay is specified in milliseconds";
}
leaf average-delay {
type oam-counter32;
units millisecond;
description
"average delay in milliseconds";
}
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leaf max-delay {
type oam-counter32;
units millisecond;
description
"Maximum delay in milliseconds";
}
description
"Monitor Statistics";
}
grouping MIP {
description
"defines MIP";
leaf interface {
type if:interface-ref;
description
"Interface";
}
}
grouping related-oam-layer {
leaf offset {
type int32 {
range "-255..255";
}
description
"defines offset (in MD levels) to a related OAM layer
+1 is the layer immediately above
-1 is the layer immediately below";
}
uses maintenance-domain-id;
uses ma-identifier;
description
"related OAM layer";
}
grouping interface-status {
description
"collection of interface related status";
leaf admin-status {
type leafref {
path "/if:interfaces-state/if:interface/if:admin-status";
}
config false;
description
"oper status from ietf-interface module";
}
leaf oper-status {
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type leafref {
path "/if:interfaces-state/if:interface/if:oper-status";
}
config false;
description
"oper status from ietf-interface module";
}
}
grouping connectivity-context {
description
"Grouping defining the connectivity context for an MA; for
example, a VRF for IP, or an LSP for MPLS. This will be
augmented by each protocol who use this component";
choice connectivity-context {
default "context-null";
case context-null {
description
"this is a place holder when no context is needed";
leaf context-null {
type empty;
description
"there is no context define";
}
}
description
"connectivity context";
}
}
grouping priority {
description
"Priority used in transmitted packets; for example, in the
TOS/DSCP field in IP or the Traffic Class field in MPLS";
leaf priority {
type uint8;
description
"priority";
}
}
grouping flow-entropy {
description
"defines the grouping statement for flow-entropy";
choice flow-entropy {
default "flow-entropy-null";
case flow-entropy-null {
description
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"this is a place holder when no flow entropy is needed";
leaf flow-entropy-null {
type empty;
description
"there is no flow entropy defined";
}
}
description
"Flow entropy";
}
}
grouping measurement-timing-group {
description
"This grouping includes objects used for
proactive and on-demand
scheduling of PM measurement sessions.";
container start-time {
description
"This container defines the session start time.";
choice start-time {
description
"Measurement sessions tart time can be immediate, relative, or
absolute.";
container immediate {
presence "Start the measurement session immediately.";
description
"Start Time of probe immediately.";
}
leaf absolute {
type yang:date-and-time;
description
"This objects specifies the scheduled start time
to perform the on-demand monitoring operations.";
}
}
}
container stop-time {
description
"This container defines the session stop time.";
choice stop-time {
description
"Measurement session stop time can be none, or absolute.";
container none {
presence "Never end the measurement session.";
description
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"Stop time is never to end.";
}
leaf absolute {
type yang:date-and-time;
description
"This objects specifies the scheduled stop time
to perform the on-demand monitoring operations.";
}
}
}
}
container domains {
description
"Contains configuration related data. Within the container
is list of fault domains. Wihin each domian has List of MA.";
list domain {
key "technology MD-name-string";
ordered-by system;
description
"Define the list of Domains within the IETF-OAM";
uses maintenance-domain-id;
uses MD-name;
leaf md-level {
type MD-level;
description
"Defines the MD-Level";
}
container MAs {
description
"This container defines MA, within that have multiple MA
and within MA have MEP, MIP";
list MA {
key "MA-name-string";
ordered-by system;
uses ma-identifier;
uses MA-name;
uses connectivity-context;
leaf mep-direction {
type MEP-direction;
mandatory true;
description
"Direction for MEPs in this MA";
}
leaf interval {
type Interval;
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default "0";
description
"Defines default Keepalive/CC Interval. May be
overridden for specific sessions if supported by the
protocol.";
}
leaf loss-threshold {
type uint32;
default "3";
description
"number of consecutive Keepalive/CC messages missed
before declaring loss of continuity fault. This is
monitored per each remote MEP session";
}
leaf ttl {
type uint8;
default "255";
description
"Time to Live";
}
uses flow-entropy {
description
"Default flow entropy in this MA, which may be
overridden for particular MEPs, sessions or
operations";
}
uses priority {
description
"Default priority for this MA, which may be overridden
for particular MEPs, sessions or operations.";
}
list MEP {
key "mep-name";
ordered-by system;
description
"contain list of MEPS";
uses MEP;
uses interface-status {
description
"status of associated interface";
}
uses flow-entropy;
uses priority;
list session {
key "session-cookie";
ordered-by user;
description
"Monitoring session to/from a particular remote MEP.
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Depending on the protocol, this could represent CC
messages received from a single remote MEP (if the
protocol uses multicast CCs) or a target to which
unicast echo request CCs are sent and from which
responses are received (if the protocol uses a
unicast request/response mechanism).";
leaf session-cookie {
type uint32;
description
"Cookie to identify different sessions, when there
are multiple remote MEPs or multiple sessions to
the same remote MEP.";
}
leaf ttl {
type uint8;
default "255";
description
"Time to Live.";
}
leaf interval {
type Interval;
description
"Transmission interval for CC packets for this
session.";
}
leaf enable {
type boolean;
default "false";
description
"enable or disable a monitor session";
}
leaf ecmp-choice {
type ecmp-choices;
description
"0 means use the specified interface
1 means use round robin";
}
leaf source-mep {
type MEP-name;
description
"Source MEP for this session, if applicable";
}
container destination-mep {
uses MEP-ID;
description
"Destination MEP";
}
container destination-mep-address {
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uses mp-address;
description
"Destination MEP Address";
}
uses connectivity-context;
uses flow-entropy;
uses priority;
list outgoing-interface {
key "interface";
leaf interface {
type if:interface-ref;
description
"Outgoing Interface";
}
description
"outgoing interfaces";
}
}
}
list MIP {
key "interface";
uses MIP;
description
"Maintenance Intermediate Point";
}
list related-oam-layer {
key "offset";
description
"List of OAM layers above and below that are related to
current MA. This allow users to easily navigate up and
down to efficiently troubleshoot a connectivity
issue";
uses related-oam-layer;
}
description
"Maintenance Association list";
}
}
}
}
notification defect-condition-notification {
description
"When defect condition is met this notificiation is sent";
uses maintenance-domain-id {
description
"defines the MD (Maintenance Domain) identifier, which is the
Generic MD-name-string and the technology.";
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}
uses ma-identifier;
leaf mep-name {
type MEP-name;
description
"Indicate which MEP is seeing the error";
}
leaf defect-type {
type identityref {
base defect-types;
}
description
"The currently active defects on the specific MEP.";
}
container generating-mepid {
uses MEP-ID;
description
"Who is generating the error (if known) if
unknown make it 0.";
}
uses error-message {
description
"Error message to indicate more details.";
}
}
rpc continuity-check {
description
"Generates continuity-check as per RFC7276 Table 4.";
input {
uses maintenance-domain-id {
description
"defines the MD (Maintenance Domain) identifier, which is
the generic
MD-name-string and the technology.";
}
uses ma-identifier {
description
"identfies the Maintenance association";
}
uses flow-entropy;
uses priority;
leaf ttl {
type uint8;
default "255";
description
"Time to Live";
}
uses session-type;
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leaf ecmp-choice {
type ecmp-choices;
description
"0 means use the specified interface
1 means use round robin";
}
leaf sub-type {
type identityref {
base command-sub-type;
}
description
"defines different command types";
}
list outgoing-interfaces {
key "interface";
leaf interface {
type if:interface-ref;
description
"outgoing interface";
}
description
"outgoing Interfaces";
}
leaf source-mep {
type MEP-name;
description
"Source MEP";
}
container destination-mp {
uses mp-address;
uses MEP-ID {
description "Only applicable if the destination is a MEP";
}
description
"Destination MEP";
}
leaf count {
type uint32;
default "3";
description
"Number of ping echo request message to send";
}
leaf interval {
type Interval;
description
"Interval between echo requests";
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}
leaf packet-size {
type uint32 {
range "64..10000";
}
default "64";
description
"Size of ping echo request packets, in octets";
}
}
output {
uses monitor-stats {
description
"Stats of continuity check.";
}
}
}
rpc continuity-verification {
if-feature connectivity-verification;
description
"Generates continuity-verification as per RFC7276 Table 4.";
input {
uses maintenance-domain-id {
description
"defines the MD (Maintenance Domain) identifier, which is
the generic
MD-name-string and the technology.";
}
uses ma-identifier {
description
"identfies the Maintenance association";
}
uses flow-entropy;
uses priority;
leaf ttl {
type uint8;
default "255";
description
"Time to Live";
}
uses session-type;
leaf ecmp-choice {
type ecmp-choices;
description
"0 means use the specified interface
1 means use round robin";
}
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leaf sub-type {
type identityref {
base command-sub-type;
}
description
"defines different command types";
}
list outgoing-interfaces {
key "interface";
leaf interface {
type if:interface-ref;
description
"outgoing interface";
}
description
"outgoing Interfaces";
}
leaf source-mep {
type MEP-name;
description
"Source MEP";
}
container destination-mp {
uses mp-address;
uses MEP-ID {
description "Only applicable if the destination is a MEP";
}
description
"Destination MEP";
}
leaf count {
type uint32;
default "3";
description
"Number of ping echo request message to send";
}
leaf interval {
type Interval;
description
"Interval between echo requests";
}
leaf packet-size {
type uint32 {
range "64..10000";
}
default "64";
description
"Size of ping echo request packets, in octets";
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}
}
output {
uses monitor-stats {
description
"Stats of continuity check.";
}
}
}
rpc path-discovery {
description
"Generates Trace-route or Path Trace and return response.
Referencing RFC7276 for common Toolset name, for IP it's
Traceroute, for MPLS OAM it's Traceroute mode, for
MPLS-TP OAM it's Route Tracing, for Pseudowire OAM it's
LSP Ping, and for TRILL OAM It's Path Tracing tool.
Starts with TTL
of one and increment by one at each hop. Untill destination
reached or TTL reach max valune";
input {
uses maintenance-domain-id {
description
"defines the MD (Maintenance Domain) identifier, which is
the generic MD-name-string and the technology.";
}
uses ma-identifier {
description
"identfies the Maintenance association";
}
uses flow-entropy;
uses priority;
leaf ttl {
type uint8;
default "255";
description
"Time to Live";
}
uses session-type;
leaf command-sub-type {
type identityref {
base command-sub-type;
}
description
"defines different command types";
}
leaf ecmp-choice {
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type ecmp-choices;
description
"0 means use the specified interface
1 means use round robin";
}
list outgoing-interfaces {
key "interface";
leaf interface {
type if:interface-ref;
description
"Interface.";
}
description
"Outgoing interface list.";
}
leaf source-mep {
type MEP-name;
description
"Source MEP";
}
container destination-mp {
uses mp-address;
uses MEP-ID {
description "Only applicable if the destination is a MEP";
}
description
"Destination MEP";
}
leaf count {
type uint32;
default "1";
description
"Number of traceroute probes to send. In protocols where a
separate message is sent at each TTL, this is the number
of packets to send at each TTL.";
}
leaf interval {
type Interval;
description
"Interval between echo requests";
}
}
output {
list response {
key "response-index";
leaf response-index {
type uint8;
description
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"Arbitrary index for the response. In protocols that
guarantee there is only a single response at each TTL
(eg IP Traceroute), the TTL can be used as the response
index.";
}
leaf ttl {
type uint8;
description
"Time to Live";
}
description
"Time to Live";
container destination-mp {
description "MP from which the response has been received";
uses mp-address;
uses MEP-ID {
description
"Only applicable if the destination is a MEP";
}
}
uses monitor-stats {
description
"If count is 1, there is a single delay value reported.";
}
}
description
"List of response.";
}
}
}
YANG module of OAM
<CODE ENDS>
6. Base Mode
The Base Mode defines default configuration that MUST be present in
the devices that comply with this document. Base Mode allows users
to have "zero-touch" experience. Several parameters require
technology specific definition.
6.1. MEP Address
In the Base Mode of operation, the MEP Address is by default the IP
address of the interface on which the MEP is located.
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6.2. MEP ID for Base Mode
In the Base Mode of operation, each device creates a single UP MEP
associated with a virtual OAM port with no physical layer (NULL PHY).
The MEPID associated with this MEP is zero (0). The choice of MEP-ID
zero is explained below.
MEPID is 2 octet field by default. It is never used on the wire
except when using CCM. Ping, traceroute and session monitoring does
not use the MEPID on its message header. It is important to have
method that can derive MEP ID of base mode in an automatic manner
with no user intervention. IP address cannot be directly used for
this purpose as the MEP ID is much smaller field. For Base Mode of
operation we propose to use MEP ID zero (0) as the default MEP-ID.
CCM packet use MEP-ID on the payload. CCM MUST NOT be used in the
Base Mode. Hence CCM MUST be disabled on the Maintenance Association
of the Base Mode.
If CCM is required, users MUST configure a separate Maintenance
association and assign unique value for the corresponding MEP IDs.
[IEEE802.1Q] CFM defines MEP ID as an unsigned integer in the range 1
to 8191. In this document we propose to extend the range to 0 to
65535. Value 0 is reserved for MEP ID of Base Mode operation and
MUST NOT be used for other purposes.
6.3. Maintenance Domain
Default MD-LEVEL is set to 3.
6.4. Maintenance Association
MAID [IEEE802.1Q] has a flexible format and includes two parts:
Maintenance Domain Name and Short MA name. In the Based Mode of
operation, the value of the Maintenance Domain Name must be the
character string "GenericBaseMode" (excluding the quotes "). In Base
Mode operation Short MA Name format is set to 2-octet integer format
(value 3 in Short MA Format field [IEEE802.1Q]) and Short MA name set
to 65532 (0xFFFC).
7. Note
This section will be removed or subject to change in the future if
any agreement is reached. As per investigation of RFC7276 for
performance Monitoring for Loss and Delay are defined for MPLS
OAM(RFC6374[RFC6374]), OWAMP (RFC4656[RFC4656]) and TWAMP
(RFC5357[RFC5357]) and TRILL OAM (RFC7456[RFC7456]). In case of
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Performance Monitoring Statistics are common between these
technologies thus generic Yang model for Performance will be worked
out through separate draft with Augmentation of Generic LIME model.
In case of Other Function, it's technology specific and thus should
be dealt in technology specific Yang model instead of Generic Model.
8. Security Considerations
The YANG module defined in this memo is designed to be accessed via
the NETCONF protocol [RFC6241] [RFC6241]. The lowest NETCONF layer
is the secure transport layer and the mandatory-to-implement secure
transport is SSH [RFC6242] [RFC6242]. The NETCONF access control
model [RFC6536] [RFC6536] provides the means to restrict access for
particular NETCONF users to a pre-configured subset of all available
NETCONF protocol operations and content.
There are a number of data nodes defined in the YANG module which are
writable/creatable/deletable (i.e., config true, which is the
default). These data nodes may be considered sensitive or vulnerable
in some network environments. Write operations (e.g., <edit-config>)
to these data nodes without proper protection can have a negative
effect on network operations.
The vulnerable "config true" subtrees and data nodes are the
following:
/goam:domains/goam:domain/
/goam:domains/goam:domain/goam:MAs/goam:MA/
/goam:domains/goam:domain/goam:MAs/goam:MA/goam:MEP
/goam:domains/goam:domain/goam:MAs/goam:MA/goam:MEP/goam:session/
Unauthorized access to any of these lists can adversely affect OAM
management system handling of end-to-end OAM and coordination of OAM
within underlying network layers This may lead to inconsistent
configuration, reporting, and presentation for the OAM mechanisms
used to manage the network.
9. IANA Considerations
This document registers a URI in the IETF XML registry [RFC3688]
[RFC3688]. Following the format in RFC 3688, the following
registration is requested to be made:
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URI: urn:ietf:params:xml:ns:yang:ietf-gen-oam
Registrant Contact: The IESG.
XML: N/A, the requested URI is an XML namespace.
This document registers a YANG module in the YANG Module Names
registry [RFC6020].
name: ietf-gen-oam namespace: urn:ietf:params:xml:ns:yang:ietf-gen-oam
prefix: goam reference: RFC XXXX
10. Acknowledgments
Giles Heron came up with the idea of developing a YANG model as a way
of creating a unified OAM API set (interface), work in this document
is largely an inspiration of that. Alexander Clemm provided many
valuable tips, comments and remarks that helped to refine the YANG
model presented in this document.
Carlos Pignataro, David Ball,Mahesh Jethanandani,Benoit
Claise,Ladislav Lhotka,GUBALLA JENS,Yuji Tochio,Gregory Mirsky, Huub
van Helvoort, Tom Taylor, Dapeng Liu participated and contributed to
this document.
11. References
11.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<http://www.rfc-editor.org/info/rfc2119>.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
<http://www.rfc-editor.org/info/rfc3688>.
[RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for
the Network Configuration Protocol (NETCONF)", RFC 6020,
DOI 10.17487/RFC6020, October 2010,
<http://www.rfc-editor.org/info/rfc6020>.
[RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
and A. Bierman, Ed., "Network Configuration Protocol
(NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
<http://www.rfc-editor.org/info/rfc6241>.
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[RFC6242] Wasserman, M., "Using the NETCONF Protocol over Secure
Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011,
<http://www.rfc-editor.org/info/rfc6242>.
[RFC6536] Bierman, A. and M. Bjorklund, "Network Configuration
Protocol (NETCONF) Access Control Model", RFC 6536,
DOI 10.17487/RFC6536, March 2012,
<http://www.rfc-editor.org/info/rfc6536>.
[RFC792] Postel, J., "Internet Control Message Protocol", RFC 792,
September 1981.
11.2. Informative References
[IEEE802.1Q]
"Media Access Control (MAC) Bridges and Virtual Bridged
Local Area Networks", IEEE Std 802.1Q-2011, August 2011.
[RFC4379] Kompella, K. and G. Swallow, "Detecting Multi-Protocol
Label Switched (MPLS) Data Plane Failures", RFC 4379,
DOI 10.17487/RFC4379, February 2006,
<http://www.rfc-editor.org/info/rfc4379>.
[RFC4443] Conta, A., Deering, S., and M. Gupta, Ed., "Internet
Control Message Protocol (ICMPv6) for the Internet
Protocol Version 6 (IPv6) Specification", RFC 4443,
DOI 10.17487/RFC4443, March 2006,
<http://www.rfc-editor.org/info/rfc4443>.
[RFC4656] Shalunov, S., Teitelbaum, B., Karp, A., Boote, J., and M.
Zekauskas, "A One-way Active Measurement Protocol
(OWAMP)", RFC 4656, DOI 10.17487/RFC4656, September 2006,
<http://www.rfc-editor.org/info/rfc4656>.
[RFC5357] Hedayat, K., Krzanowski, R., Morton, A., Yum, K., and J.
Babiarz, "A Two-Way Active Measurement Protocol (TWAMP)",
RFC 5357, DOI 10.17487/RFC5357, October 2008,
<http://www.rfc-editor.org/info/rfc5357>.
[RFC6291] Andersson, L., van Helvoort, H., Bonica, R., Romascanu,
D., and S. Mansfield, "Guidelines for the Use of the "OAM"
Acronym in the IETF", BCP 161, RFC 6291,
DOI 10.17487/RFC6291, June 2011,
<http://www.rfc-editor.org/info/rfc6291>.
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[RFC6325] Perlman, R., Eastlake 3rd, D., Dutt, D., Gai, S., and A.
Ghanwani, "Routing Bridges (RBridges): Base Protocol
Specification", RFC 6325, DOI 10.17487/RFC6325, July 2011,
<http://www.rfc-editor.org/info/rfc6325>.
[RFC6371] Busi, I., Ed. and D. Allan, Ed., "Operations,
Administration, and Maintenance Framework for MPLS-Based
Transport Networks", RFC 6371, DOI 10.17487/RFC6371,
September 2011, <http://www.rfc-editor.org/info/rfc6371>.
[RFC6374] Frost, D. and S. Bryant, "Packet Loss and Delay
Measurement for MPLS Networks", RFC 6374,
DOI 10.17487/RFC6374, September 2011,
<http://www.rfc-editor.org/info/rfc6374>.
[RFC7174] Salam, S., Senevirathne, T., Aldrin, S., and D. Eastlake
3rd, "Transparent Interconnection of Lots of Links (TRILL)
Operations, Administration, and Maintenance (OAM)
Framework", RFC 7174, DOI 10.17487/RFC7174, May 2014,
<http://www.rfc-editor.org/info/rfc7174>.
[RFC7276] Mizrahi, T., Sprecher, N., Bellagamba, E., and Y.
Weingarten, "An Overview of Operations, Administration,
and Maintenance (OAM) Tools", RFC 7276,
DOI 10.17487/RFC7276, June 2014,
<http://www.rfc-editor.org/info/rfc7276>.
[RFC7455] Senevirathne, T., Finn, N., Salam, S., Kumar, D., Eastlake
3rd, D., Aldrin, S., and Y. Li, "Transparent
Interconnection of Lots of Links (TRILL): Fault
Management", RFC 7455, DOI 10.17487/RFC7455, March 2015,
<http://www.rfc-editor.org/info/rfc7455>.
[RFC7456] Mizrahi, T., Senevirathne, T., Salam, S., Kumar, D., and
D. Eastlake 3rd, "Loss and Delay Measurement in
Transparent Interconnection of Lots of Links (TRILL)",
RFC 7456, DOI 10.17487/RFC7456, March 2015,
<http://www.rfc-editor.org/info/rfc7456>.
[Y.1731] "OAM functions and mechanisms for Ethernet based
networks", ITU-T Recommendation G.8013/Y.1731, 2013.
Authors' Addresses
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Tissa Senevirathne
CISCO Systems
375 East Tasman Drive.
San Jose, CA 95134
USA
Phone: 408-853-2291
Email: tsenevir@cisco.com
Norman Finn
CISCO Systems
510 McCarthy Blvd
Milpitas, CA 95035
USA
Email: nfinn@cisco.com
Deepak Kumar (editor)
CISCO Systems
510 McCarthy Blvd
Milpitas, CA 95035
USA
Email: dekumar@cisco.com
Samer Salam
CISCO Systems
595 Burrard St. Suite 2123
Vancouver, BC V7X 1J1
Canada
Email: ssalam@cisco.com
Qin Wu (editor)
Huawei
101 Software Avenue, Yuhua District
Nanjing, Jiangsu 210012
China
Email: bill.wu@huawei.com
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Michael Wang
Huawei Technologies,Co.,Ltd
101 Software Avenue, Yuhua District
Nanjing 210012
China
Email: wangzitao@huawei.com
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