Internet DRAFT - draft-zhang-pwe3-iccp-stp
draft-zhang-pwe3-iccp-stp
INTERNET-DRAFT Mingui Zhang
Intended Status: Proposed Standard Huafeng Wen
Expires: June 27, 2014 Huawei
Jie Hu
China Telecom
December 24, 2013
STP Application of ICCP
draft-zhang-pwe3-iccp-stp-01.txt
Abstract
Inter-Chassis Communication Protocol (ICCP) supports the inter-
chassis redundancy mechanism which achieves high network
availability.
In this document, the PEs in a Redundant Group (RG) running ICCP are
used to offer multi-homed connectivity to Spanning Tree Protocol
(STP) networks. The ICCP TLVs for the STP application are defined,
therefore PEs from the RG can make use of these TLVs to synchronize
the state and configuration data of the STP network.
Status of this Memo
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Copyright and License Notice
Copyright (c) 2013 IETF Trust and the persons identified as the
document authors. All rights reserved.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Conventions used in this document . . . . . . . . . . . . . 3
1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . 3
2. The Use Case Scenario . . . . . . . . . . . . . . . . . . . . . 3
2.1. STP as an Application of ICCP . . . . . . . . . . . . . . . 4
2.2. A Private Solution: The BPDU Tunneling Model . . . . . . . 4
3. Spanning Tree Protocol Application TLVs . . . . . . . . . . . . 6
3.1. STP Connect TLV . . . . . . . . . . . . . . . . . . . . . . 6
3.2. STP Disconnect TLV . . . . . . . . . . . . . . . . . . . . 7
3.2.1. STP Disconnect Cause TLV . . . . . . . . . . . . . . . 8
3.3. STP Config TLVs . . . . . . . . . . . . . . . . . . . . . . 8
3.3.1. STP System Config . . . . . . . . . . . . . . . . . . . 8
3.3.2. STP Topology Changed Instances . . . . . . . . . . . . 9
3.3.3. STP CIST Root Time . . . . . . . . . . . . . . . . . . 10
3.3.4. STP MSTI Root Time . . . . . . . . . . . . . . . . . . 11
3.3.5. STP Region Name . . . . . . . . . . . . . . . . . . . . 12
3.3.6. STP Revision Level . . . . . . . . . . . . . . . . . . 12
3.3.7. STP Instance Priority . . . . . . . . . . . . . . . . . 13
3.3.8. STP Configuration Digest . . . . . . . . . . . . . . . 14
3.4. STP Synchronization Request TLV . . . . . . . . . . . . . . 14
3.5. STP Synchronization Data TLV . . . . . . . . . . . . . . . 16
4. Security Considerations . . . . . . . . . . . . . . . . . . . . 17
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 17
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . 17
6. References . . . . . . . . . . . . . . . . . . . . . . . . . . 17
6.1. Normative References . . . . . . . . . . . . . . . . . . . 17
6.2. Informative References . . . . . . . . . . . . . . . . . . 17
Author's Addresses . . . . . . . . . . . . . . . . . . . . . . . . 19
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1. Introduction
Inter-Chassis Communication Protocol (ICCP) specifies a multi-chassis
redundant mechanism, which enables PEs located in multi-chassis to
act as a single Redundant Group (RG).
This document introduces Spanning Tree Protocol (STP) as a new
application of ICCP. When a bridge network running STP is connected
to a RG, the RG members should pretend to be a single root bridge to
participate the operations of the STP. STP relevant information need
be exchanged and synchronized among the RG members. ICCP TLVs for the
Spanning Tree Protocol application are specified for this purpose.
1.1. 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 RFC 2119 [RFC2119].
1.2. Terminology
STP: Spanning Tree Protocol
MSTP: Multiple Spanning Tree Protocol
DSLAM: Digital Subscriber Line Access Multiplexer
MST: Multiple Spanning Trees
CIST: Common and Internal Spanning Tree
MSTI: Multiple Spanning Tree Instance
BPDU: Bridge Protocol Data Unit
In this document, unless otherwise explicitly noted, when the term
STP is used, it also covers MSTP.
2. The Use Case Scenario
In customers' broadband networks, bridged DSLAMs are usually
geographically dispersed. It is a common case these DSLAMs are
connected to carriers' L2VPN network at multiple points for the sake
of reliability. Requirements from customers for this use case are
listed as follows.
o These DSLAMs are running STP.
o These DSLAMs are not geo-close to each other. Multiple DSLAMs are
connected to the carrier network at different locations.
o When one connection to the carrier network fails, customers wish a
connection in another location can continue to work after the re-
convergence of the STP rather than compromising the whole STP
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network. The failure of the connection may be due to the failure
of the PE, the AC or even the CE (a DSLAM) itself.
o Customers want to balance the load among those connections,
therefore all these connections need be active.
In order to meet these requirements, the 'ICCP-STP' model is proposed
in Section 2.1. It introduces STP as a new application of ICCP. A
private implementation is depicted in Section 2.2 to serve as a
contrast. Its issues are analyzed.
2.1. STP as an Application of ICCP
+--------------+ +=============+
| | | |
| | | |
| +---+ | | +-----+ |
| +---+CE1+<6>-------<5>+ PE1 | |
| <1> +---+ | | +-----+ |
| +-+-+ | | || |
| |CE3| | | || ICCP |
| +-+-+ | | || |
| <2> +---+ | | +-----+ |
| +---+CE2+<3>-------<4>+ PE2 | |
| +---+ | | +-----+ |
| | | |
| Multi-homed | | |
| STP Network | | |
+--------------+ +=============+
Figure 2.1: A STP network is multi-homed to an RG running ICCP.
Figure 2.1 shows an example topology of this model. With ICCP, the
whole RG will be virtualized to be a single bridge. The RG pretends
that the ports connected to the STP network (port <4>, <5>) are from
the same bridge. All these ports emit configuration BPDU with the
highest root priority to trigger the construction of the spanning
tree. In this way, the STP will always broken a loop within the
multi-homed STP network.
Each RG member has its BridgeIdentifier (the MAC address). The least
significant one is elected as the BridgeIdentifier of the 'vitualized
root bridge'.
2.2. A Private Solution: The BPDU Tunneling Model
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+--------------+ +=============+
| | | |
| | | |
| +---+ | | +-----+ |
| +---+CE1+<6>-------<5>+ PE1 | |
| <1> +---+ | | +-----+ |
| +-+-+ | | ||BPDU |
| |CE3| | | ||tunnel|
| +-+-+ | | || |
| <2> +---+ | | +-----+ |
| +---+CE2+<3>-------<4>+ PE2 | |
| +---+ | | +-----+ |
| | | |
| Multi-homed | | |
| STP Network | | |
+--------------+ +=============+
Figure 2.2: The BPDU Tunneling Model
Figure 2.2 shows an example network of the 'BPDU tunneling' model.
Two PEs tunnel BPDUs of the STP network over PW. The OAM designed in
RFC 7023 can be adopted for the interworking between MPLS and
Ethernet.
In this model, the ports connected to the STP network at the PEs'
side are non-bridge ports (e.g., port <4>, <5>). The tunnel between
PE1 and PE2 is a transparent tunnel of BPDUs. For CE1 and CE2, they
regard that there is a direct link between them. Issues of this model
are listed as follows.
o Assume port <1> was blocked according to the STP calculation. Now,
suppose link CE3-CE2 fails, port <2> is blocked while port <1> is
unblocked. Since the BPDUs is just tunneled, PE2 is unaware of
this change. It may continue to send traffic to CE3 via CE2 where
a black-hole happens.
In order to handle this issue, PEs have to snoop the Topology
Change (TC) message of the STP network so the tunnel is not
"transparent" to BPDUs anymore. When the TC event is sensed, these
PEs should withdraw MAC addresses of those instances affected by
the TC event across the carrier's network.
o When port <4> fails, CE1 is unaware. Suppose CE2 is the root
bridge, port <6> has to wait for 3 STP HELLO Intervals (3*2s) and
2 Forwarding Delays (2*15s). The STP network takes at least 36
seconds to complete the convergence. The convergence process of
the STP network is greatly slowed down. This actually changes the
behavior of customers' STP networks.
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In order to speed up the convergence, CE1 has to sense the state
of the link between CE2 and PE2. The interworking PEs and CEs have
to cope with various combinations of failures. There is no
standard solution yet.
o RFC 7023 is scoped to only single segment PWs [RFC6310][RFC 7023].
When the STP network is attached to more than two PEs, a full mesh
PWs have to be set up. It's not clear yet what behaviors these PEs
should have.
Compared with this 'BPDU tunneling' model, the advantage point of the
"ICCP-STP" model is that PEs "participate" in the STP calculation,
therefore we need not design the complex interworking mechanism.
3. Spanning Tree Protocol Application TLVs
This section discusses the ICCP TLVs for the Spanning Tree Protocol
application.
3.1. STP Connect TLV
This TLV is included in the RG Connect message to signal the
establishment of STP application connection.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|U|F| Type=TBD | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Protocol Version |A| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Optional Sub-TLVs |
~ ~
| |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- U and F Bits
Both are set to 0.
- Type
set to TBD for "STP Connect TLV"
- Length
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Length of the TLV in octets excluding the U-bit, F-bit, Type,
and Length fields.
- Protocol Version
The version of this particular protocol for the purposes of
ICCP. This is set to 0x0001.
- A bit
Acknowledgement Bit. Set to 1 if the sender has received a STP
Connect TLV from the recipient. Otherwise, set to 0.
- Reserved
Reserved for future use.
- Optional Sub-TLVs
There are no optional Sub-TLVs defined for this version of the
protocol.
3.2. STP Disconnect TLV
This TLV is used in an RG Disconnect Message to indicate that the
connection for the STP application is to be terminated.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|U|F| Type=TBD | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Optional Sub-TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- U and F Bits
Both are set to 0.
- Type
set to TBD for "STP Disconnect TLV"
- Length
Length of the TLV in octets excluding the U-bit, F-bit, Type,
and Length fields.
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- Optional Sub-TLVs
The only optional Sub-TLV defined for this version of the
protocol is the "STP Disconnect Cause" TLV defined next:
3.2.1. STP Disconnect Cause TLV
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|U|F| Type=TBD | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Disconnect Cause String |
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- U and F Bits
Both are set to 0.
- Type
set to TBD for "STP Disconnect Cause TLV"
- Length
Length of the TLV in octets excluding the U-bit, F-bit, Type,
and Length fields.
- Disconnect Cause String
Variable length string specifying the reason for the disconnect.
Used for network management.
3.3. STP Config TLVs
The STP Config TLVs are sent in the RG Application Data message. When
a STP Config TLV is received by a peering RB member, it SHOULD
synchronize the configuration information contained in the TLV. TLVs
specified from section 3.3.1 through section 3.3.9 contains such kind
of configuration information.
3.3.1. STP System Config
This TLV announces the local node's STP System Parameters to the RG
peers.
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0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|U|F| Type=TBD | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ROID |
+ +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MAC Address |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- U and F Bits
Both are set to 0.
- Type
set to TBD for "STP System Config"
- Length
Length of the MAC address, which is 6 octets.
-ROID
As defined in the ROID section of [ICCP].
- MAC Address
The MAC address of the sender. This MAC address is set to the
BridgeIdentifier of the sender, as defined in [802.1q] section
13.23.2. The the least significant unsigned BridgeIdentifier is
used as the MAC address of the Virtual Root Bridge mentioned in
Section 2.1.
3.3.2. STP Topology Changed Instances
This TLV is used to report the Topology Changed Instances to other
members in the RG. The receiver RG member SHOULD enforce the Topology
Change to its port connected to the STP network, including the flush
out of MAC addresses relevant to the instances listed in this TLV.
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0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|U|F| Type=TBD | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| InstanceID List |
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- U and F Bits
Both are set to 0.
- Type
set to TBD for "STP Topology Changed Instances"
- Length
Length of the TLV in octets excluding the U-bit, F-bit, Type,
and Length fields.
- InstanceID List
The list of the instances whose topology is changed as indicated
by the Topology Change Notification (TCN) Messages as specified
in [802.1q] section 13.14.
3.3.3. STP CIST Root Time
This TLV is used to report the Value of CIST Root Time to other
members in the RG.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|U|F| Type=TBD | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MaxAge | MessageAge | FwdDelay | HelloTime |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RemainingHops |
+-+-+-+-+-+-+-+-+
- U and F Bits
Both are set to 0.
- Type
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set to TBD for "STP CIST Root Time"
- Length
Length of the TLV in octets excluding the U-bit, F-bit, Type,
and Length fields.
- MaxAge
The Maximum Age of this TLV.
- MessageAge
The actual age of this TLV.
- FwdDelay
The delay before the port enters the forwarding status.
- HelloTime
The interval between two continuous configuration BPDUs.
- RemainingHops
The remaining hops of this TLV
3.3.4. STP MSTI Root Time
This TLV is used to report the Value of MSTI Root Time to other
members in the RG.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|U|F| Type=TBD | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| InstanceID | RemainingHops |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- U and F Bits
Both are set to 0.
- Type
set to TBD for "STP MSTI Root Time"
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- Length
Length of the TLV in octets excluding the U-bit, F-bit, Type,
and Length fields.
- InstanceID
The instance identification number of the MSTI.
- remainingHops
The remaining hops of this TLV
3.3.5. STP Region Name
This TLV is used to report the Value of Region Name to other members
in the RG.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|U|F| Type=TBD | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Region Name |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- U and F Bits
Both are set to 0.
- Type
set to TBD for "STP Region Name"
- Length
Length of the TLV in octets excluding the U-bit, F-bit, Type,
and Length fields.
- Region Name
The Name of the MST Region.
3.3.6. STP Revision Level
This TLV is used to report the Value of Revision Level to other
members in the RG.
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0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|U|F| Type=TBD | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Revision Level |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- U and F Bits
Both are set to 0.
- Type
set to TBD for "STP Revision Level"
- Length
Length of the TLV in octets excluding the U-bit, F-bit, Type,
and Length fields.
- Revision Level
The Revision Level as specified in [802.1q] section 3.21;
3.3.7. STP Instance Priority
This TLV is used to report the Value of Instance Priority to other
members in the RG.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|U|F| Type=TBD | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Pri | InstanceID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- U and F Bits
Both are set to 0.
- Type
set to TBD for "STP Instance Priority"
- Length
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Length of the TLV in octets excluding the U-bit, F-bit, Type,
and Length fields.
- Pri
The Instance Priority
- InstanceID
The instance identification number of the MSTI.
3.3.8. STP Configuration Digest
This TLV is used to report the Value of STP VLAN Instance Mapping to
other members in the RG.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|U|F| Type=TBD | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Configuration Digest |
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- U and F Bits
Both are set to 0.
- Type
set to TBD for "STP Configuration Digest"
- Length
Length of the STP Configuration Digest which is 16 octets.
- Configuration Digest
As specified in [802.1q] section 13.7.
3.4. STP Synchronization Request TLV
The STP Synchronization Request TLV is used in the RG Application
Data message. This TLV is used by a device to request from its peer
to re-transmit configuration or operational state. The following
information can be requested:
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- system configuration and/or state
- configuration and/or state for a specific port
The format of the TLV is as follows:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|U|F| Type=TBD | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Request Number |C|S| Request Type |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Port Number | Actor Key |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- U and F Bits
Both are set to 0.
- Type
set to TBD for "STP Synchronization Request TLV"
- Length
Length of the TLV in octets excluding the U-bit, F-bit, Type,
and Length fields.
- Request Number
2 octets. Unsigned integer uniquely identifying the request.
Used to match the request with a response. The value of 0 is
reserved for unsolicited synchronization, and MUST NOT be used
in the STP Synchronization Request TLV.
- C Bit
Set to 1 if request is for configuration data. Otherwise, set to
0.
- S Bit
Set to 1 if request is for running state data. Otherwise, set to
0.
- Request Type
14-bits specifying the request type, encoded as follows:
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0x00 Request System Data
0x01 Request Port Data
0x3FFF Request All Data
- Port Number
2 octets. When Request Type field is set to 'Request Port Data',
this field encodes the STP Port Number for the requested port.
When the value of this field is 0, it denotes that all ports,
whose STP Key is specified in the "Actor Key" field, are being
requested.
- Actor Key
2 octets. STP Actor key for the corresponding port. When the
value of this field is 0 (and the Port Number field is 0 as
well), it denotes that information for all ports in the system
is being requested.
3.5. STP Synchronization Data TLV
The STP Synchronization Data TLV is used in the RG Application Data
message. A pair of these TLVs is used by a device to delimit a set of
TLVs that are being transmitted in response to an STP Synchronization
Request TLV. The delimiting TLVs signal the start and end of the
synchronization data, and associate the response with its
corresponding request via the 'Request Number' field.
The STP Synchronization Data TLVs are also used for unsolicited
advertisements of complete STP configuration and operational state
data. The 'Request Number' field MUST be set to 0 in this case.
This TLV has the following format:
- U and F Bits
Both are set to 0.
- Type
set to TBD for "STP Synchronization Data TLV"
- Length
Length of the TLV in octets excluding the U-bit, F-bit, Type,
and Length fields.
- Request Number
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2 octets. Unsigned integer identifying the Request Number from
the "STP Synchronization Request TLV" which solicited this
synchronization data response.
- Flags
2 octets, response flags encoded as follows:
0x00 Synchronization Data Start
0x01 Synchronization Data End
4. Security Considerations
This document raises no new security issues.
5. IANA Considerations
The types used by the application TLVs defined in Section 3 should be
assigned.
Acknowledgements
The authors would like to thank the comments and suggestions from
Gregory Mirsky.
6. References
6.1. Normative References
[ICCP] L. Martini, S. Salam, et al, "Inter-Chassis Communication
Protocol for L2VPN PE Redundancy", draft-ietf-pwe3-iccp-12.txt,
work in progress.
[RFC7023] D. Mohan, Ed., N. Bitar, Ed., A. Sajassi, Ed., S. DeLord,
P. Niger, R. Qiu., "MPLS and Ethernet Operations,
Administration, and Maintenance (OAM) Interworking", RFC 7023,
October 2013.
6.2. Informative References
[RFC6310] Aissaoui, M., Busschbach, P., Martini, L., Morrow, M.,
Nadeau, T., and Y(J). Stein, "Pseudowire (PW) Operations,
Administration, and Maintenance (OAM) Message Mapping", RFC
6310, July 2011.
[802.1q] "IEEE Standard for Local and Metropolitan Area Networks---
Virtual Bridged Local Area Networks.". IEEE Std 802.1 Q-2005,
May 19, 2006.
Mingui Zhang Expires June 27, 2014 [Page 17]
INTERNET-DRAFT STP Application of ICCP December 24, 2013
Mingui Zhang Expires June 27, 2014 [Page 18]
INTERNET-DRAFT STP Application of ICCP December 24, 2013
Author's Addresses
Mingui Zhang
Huawei
Email: zhangmingui@huawei.com
Huafeng Wen
Huawei
Email: wenhuafeng@huawei.com
Jie Hu
China Telecom
Email: hujie@ctbri.com.cn
Mingui Zhang Expires June 27, 2014 [Page 19]