One document matched: draft-martini-pwe3-iccp-00.txt
,Au Nadeau "Thomas D. Nadeau" "BT"
PWE3 Working Group Luca Martini
Internet Draft Cisco
Expires: December 2008 Samer Salam
Cisco
Satoru Matsushima Ali Sajassi
Softbank Cisco
June 2008
Inter-Chassis Communication Protocol for L2VPN PE Redundancy
draft-martini-pwe3-iccp-00.txt
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Abstract
This document specifies an inter-chassis communication protocol
(ICCP) that enables PE redundancy for Virtual Private Wire Service
(VPWS) and Virtual Private LAN Service (VPLS) applications. The
protocol runs within a set of two or more PEs, forming a redundancy
group, for the purpose of synchronizing data amongst the systems. It
accommodates multi-chassis attachment circuit as well as pseudowire
redundancy mechanisms.
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Table of Contents
1 Specification of Requirements ........................ 3
2 Acknowledgments ...................................... 3
3 Introduction ......................................... 3
4 ICCP Overview ........................................ 4
4.1 Redundancy Model & Topology .......................... 4
4.2 ICCP Interconnect Scenarios .......................... 5
4.2.1 Co-located Dedicated Interconnect .................... 5
4.2.2 Co-located Shared Interconnect ....................... 6
4.2.3 Geo-redundant Dedicated Interconnect ................. 7
4.2.4 Geo-redundant Shared Interconnect .................... 8
4.3 ICCP Requirements .................................... 9
5 ICC LDP Protocol extension Specification ............. 10
5.1 LDP ICC capability advertisement ..................... 11
5.2 RG Membership Management ............................. 11
5.3 Application Connection Management .................... 12
5.4 Application Data Transfer ............................ 12
6 ICCP PE Node Failure Detection Mechanism ............. 13
7 ICCP Message Formats ................................. 14
7.1 Encoding ICC into LDP messages ...................... 14
7.1.1 ICC Header ........................................... 14
7.1.2 Message Encoding ..................................... 16
7.2 RG Connect Message ................................... 17
7.2.1 Sender Name TLV ...................................... 18
7.3 RG Disconnect Message ................................ 19
7.4 RG Notification Message .............................. 20
7.4.1 Notification Message TLVs ............................ 21
7.5 RG Application Data Message .......................... 23
7.6 Application TLVs ..................................... 24
7.6.1 Pseudowire Redundancy (PW-RED) Application TLVs ...... 24
7.6.1.1 PW-RED Connect TLV ................................... 24
7.6.1.2 PW-RED Disconnect TLV ................................ 25
7.6.1.3 PW-RED Config TLV .................................... 25
7.6.1.4 Service Name TLV ..................................... 26
7.6.1.5 PW ID TLV ............................................ 26
7.6.1.6 Generalized PW ID TLV ................................ 27
8 LDP Capability Negotiation ........................... 29
9 Client Applications .................................. 30
9.1 Pseudowire Redundancy Application Procedures ......... 30
9.1.1 Initial Setup ........................................ 30
9.1.2 Pseudowire Configuration ............................. 30
9.1.3 Pseudowire Status Synchronization .................... 31
9.1.4 PE Node Failure ...................................... 31
9.2 Attachment Circuit Redundancy Application Procedures . 32
9.2.1 Common AC Procedures ................................. 32
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9.2.1.1 AC Failure ........................................... 32
9.2.1.2 PE Node Failure ...................................... 32
9.2.1.3 PE Isolation ......................................... 32
9.2.2 ATM AC Procedures .................................... 32
9.2.3 Frame Relay AC Procedures ............................ 33
9.2.4 Ethernet AC Procedures ............................... 33
10 Security Considerations .............................. 33
11 IANA Considerations .................................. 33
11.1 MESSAGE TYPE NAME SPACE .............................. 33
11.2 TLV TYPE NAME SPACE .................................. 33
11.3 ICC RG Parameter Type Space .......................... 34
11.4 STATUS CODE NAME SPACE ............................... 34
12 Full Copyright Statement ............................. 35
13 Intellectual Property Statement ...................... 35
14 Normative References ................................. 36
15 Informative References ............................... 36
16 Author Information ................................... 36
1. Specification of Requirements
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.
2. Acknowledgments
The authors wish to acknowledge the important contributions of Neil
McGill and Amir Maleki.
3. Introduction
Network availability is a critical metric for service providers as it
has a direct bearing on their profitability. Outages translate not
only to lost revenue but also to potential penalties mandated by
contractual agreements with customers running mission-critical
applications that require tight SLAs. This is true for any carrier
network, and networks employing Layer2 Virtual Private Network
(L2VPN) technology are no exception. Network high-availability can be
achieved by employing intra and inter-chassis redundancy mechanisms.
The focus of this document is on the latter. The document defines an
Inter-Chassis Communication Protocol (ICCP) that allows
synchronization of state and configuration data between a set of two
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or more PEs forming a Redundancy Group (RG). The protocol supports
multi-chassis redundancy mechanisms that can be employed on either
the attachment circuit or pseudowire front.
4. ICCP Overview
4.1. Redundancy Model & Topology
The focus of this document is on PE node redundancy. It is assumed
that a set of two or more PE nodes are designated by the operator to
form a Redundancy Group (RG). Members of a Redundancy Group fall
under a single administration (e.g. service provider) and employ a
common redundancy mechanism towards the access (attachment circuits
or access pseudowires) and/or towards the core (pseudowires) for any
given service instance. It is possible, however, for members of an RG
to make use of disparate redundancy mechanisms for disjoint services.
The PE devices may be offering any type of L2VPN service, i.e. VPWS
or VPLS. As a matter of fact, the use of ICCP may even be applicable
for Layer 3 service redundancy, but this is considered to be outside
the scope of this document.
The PEs in an RG offer multi-homed connectivity to either individual
devices (e.g. CE, DSLAM, etc...) or entire networks (e.g. access
network). Figure 1 below depicts the model.
+=================+
| |
Mutli-homed +----+ | +-----+ |
Node ------------> | CE |-------|--| PE1 ||<------|---Pseudowire-->|
| |--+ -|--| ||<------|---Pseudowire-->|
+----+ | / | +-----+ |
| / | || |
|/ | || ICCP |--> Towards Core
+-------------+ / | || |
| | /| | +-----+ |
| Access |/ +----|--| PE2 ||<------|---Pseudowire-->|
| Network |-------|--| ||<------|---Pseudowire-->|
| | | +-----+ |
| | | |
+-------------+ | Redundancy |
^ | Group |
| +=================+
|
Multi-homed Network
Figure 1: Generic Multi-chassis Redundancy Model
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In the topology of Figure 1, the redundancy mechanism employed
towards the access node/network can be one of a multitude of
technologies, e.g. it could be IEEE 802.3ad Link Aggregation Groups
with Link Aggregation Control Protocol (LACP), or SONET APS. The
specifics of the mechanism are out of the scope of this document.
However, it is assumed that the PEs in the RG are required to
communicate amongst each other in order for the access redundancy
mechanism to operate correctly. As such, it is required to run an
inter-chassis communication protocol among the PEs in the RG in order
to synchronize configuration and/or running state data.
Furthermore, the presence of the inter-chassis communication channel
allows simplification of the pseudowire redundancy mechanism. This is
primarily because it allows the PEs within an RG to run some
arbitration algorithm to elect which pseudowire(s) should be in
active or standby mode for a given service instance. The PEs can then
advertise the outcome of the arbitration to the remote-end PE(s), as
opposed to having to embed a hand-shake procedure into the pseudowire
redundancy status communication mechanism, and every other possible
Layer 2 status communication mechanism.
4.2. ICCP Interconnect Scenarios
When referring to 'interconnect' in this section, we are concerned
with the links or networks over which Inter-Chassis Communication
Protocol messages are transported, and not normal data traffic
between PEs. The PEs which are members of an RG may be either
physically co-located or geo-redundant. Furthermore, the physical
interconnect between the PEs over which ICCP is to run may comprise
of either dedicated back-to-back links or a shared connection through
the PSN network (e.g., core). This gives rise to a matrix of four
interconnect scenarios, described next.
4.2.1. Co-located Dedicated Interconnect
In this scenario, the PEs within an RG are co-located in the same
physical location (POP, CO). Furthermore, dedicated links provide the
interconnect for ICCP among the PEs.
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+=================+ +-----------------+
|CO | | |
| +-----+ | | |
| | PE1 |________|_____| |
| | | | | |
| +-----+ | | |
| || | | |
| || ICCP | | Core |
| || | | Network |
| +-----+ | | |
| | PE2 |________|_____| |
| | | | | |
| +-----+ | | |
| | | |
+=================+ +-----------------+
Figure 2: ICCP Co-located PEs Dedicated Interconnect Scenario
Given that the PEs are connected back-to-back in this case, it is
possible to rely on Layer 2 redundancy mechanisms to guarantee the
robustness of the links carrying the ICCP. For example, if the
interconnect comprises of IEEE 802.3 Ethernet links, it is possible
to provide redundant interconnect by means of IEEE 802.3ad Link
Aggregation Groups.
4.2.2. Co-located Shared Interconnect
In this scenario, the PEs within an RG are co-located in the same
physical location (POP, CO). However, unlike the previous scenario,
there are no dedicated links between the PEs. The interconnect for
ICCP is provided through the core network to which the PEs are
connected. Figure 3 depicts this model.
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+=================+ +-----------------+
|CO | | |
| +-----+ | | |
| | PE1 |________|_____| |
| | |<=================+ |
| +-----+ ICCP | | || |
| | | || |
| | | || Core |
| | | || Network |
| +-----+ | | || |
| | PE2 |________|_____| || |
| | |<=================+ |
| +-----+ | | |
| | | |
+=================+ +-----------------+
Figure 3: ICCP Co-located PEs Shared Interconnect Scenario
Given that the PEs in the RG are connected over the Packet Switched
Network (PSN), then PSN Layer mechanisms can be leveraged to ensure
the resiliency of the interconnect against connectivity failures. For
example, it is possible to employ RSVP LSPs with FRR and/or end-to-
end backup LSPs.
4.2.3. Geo-redundant Dedicated Interconnect
In this variation, the PEs within a Redundancy Group are located in
different physical locations to provide geographic redundancy. This
may be desirable, for example, to protect against natural disasters
or the like. A dedicated interconnect is provided to link the PEs,
which is a costly option, especially when considering the possibility
of providing multiple such links for interconnect robustness. Because
of this particular reason, it is anticipated that this interconnect
scenario will not be common for most commercial applications. The
resiliency mechanisms for the interconnect are similar to those
highlighted in the co-located interconnect counterpart.
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+=================+ +-----------------+
|CO 1 | | |
| +-----+ | | |
| | PE1 |________|_____| |
| | | | | |
| +-----+ | | |
+=====||==========+ | |
|| ICCP | Core |
+=====||==========+ | Network |
| +-----+ | | |
| | PE2 |________|_____| |
| | | | | |
| +-----+ | | |
|CO 2 | | |
+=================+ +-----------------+
Figure 4: ICCP Geo-redundant PEs Dedicated Interconnect Scenario
4.2.4. Geo-redundant Shared Interconnect
In this scenario, the PEs of an RG are located in different physical
locations and the interconnect for ICCP is provided over the PSN
network to which the PEs are connected. This interconnect option is
more likely to be the one used for geo-redundancy as it is more
economically appealing compared to the geo-redundant dedicated
interconnect. The resiliency mechanisms that can be employed to
guarantee the robustness of the ICCP transport are PSN Layer
mechanisms as has been described in a previous section.
+=================+ +-----------------+
|CO 1 | | |
| +-----+ | | |
| | PE1 |________|_____| |
| | |<=================+ |
| +-----+ ICCP | | || |
+=================+ | || |
| || Core |
+=================+ | || Network |
| +-----+ | | || |
| | PE2 |________|_____| || |
| | |<=================+ |
| +-----+ | | |
|CO 2 | | |
+=================+ +-----------------+
Figure 5: ICCP Geo-redundant PEs Shared Interconnect Scenario
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4.3. ICCP Requirements
The Inter-chassis Communication Protocol should satisfy the following
requirements:
-i. Provide control channel for communication between PEs in
Redundancy Group (RG). Nodes maybe co-located or remote
(refer to Interconnect Scenarios section above). It is
expected that client applications which make use of ICCP
services will only use this channel to communicate control
information and not data-traffic. As such the protocol
should cater for low-bandwidth, low-delay and highly
reliable message transfer.
-ii. Accommodate multiple client applications (e.g. multi-chassis
LACP, PW redundancy, SONET APS, etc...). This implies that
the messages should be extensible (e.g. TLV-based) and the
protocol should provide a robust application registration
and versioning scheme.
-iii. Provide reliable message transport and in-order delivery
between nodes in a RG with secure authentication mechanisms
built into the protocol. The redundancy applications that
are clients of ICCP expect reliable message transfer, and as
such will assume that the protocol takes care of flow-
control and retransmissions. Furthermore, given that the
applications will rely on ICCP to communicate data used to
synchronize state-machines on disparate nodes, it is
critical that ICCP guarantees in-order message delivery.
Loss of messages or out-of-sequence messages would have
adverse side-effects to the operation of the client
applications.
-iv. Provide a common mechanism to actively monitor the health of
PEs in an RG. This mechanism will be used to detect PE node
failure and inform the client applications. The applications
require this to trigger failover according to the procedures
of the employed redundancy protocol on the AC and PW. It is
desired to achieve sub-second detection of loss of remote
node (~ 50 - 150 msec) in order to give the client
applications (redundancy mechanisms) enough reaction time to
achieve sub-second service restoration time.
-v. Provide asynchronous event-driven state update, independent
of periodic messages, for immediate notification of client
applications' state changes. In other words, the
transmission of messages carrying application data should be
on-demand rather than timer-based to minimize inter-chassis
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state synchronization delay.
-vi. Accommodate multi-link and multi-hop interconnect between
nodes. When the devices within an RG are located in
different physical locations, the physical interconnect
between them will comprise of a network rather than a link.
As such, ICCP should accommodate the case where the
interconnect involves multiple hops. Furthermore, it is
possible to have multiple (redundant) paths or interconnects
between a given pair of devices. This is true for both the
co-located and geo-redundant scenarios. ICCP should handle
this as well.
-vii. Ensure transport security between devices in an RG. This is
especially important in the scenario where the members of an
RG are located in different physical locations and connected
over a shared (e.g. PSN) network.
-viii. Must allow operator to statically configure members of RG.
Auto-discovery may be considered in the future.
-ix. Allow for flexible RG membership. It is expected that only
two nodes per an RG will cover most of the redundancy
applications for common deployments. However, ICCP should
not preclude supporting more than two nodes in an RG by
virtue of design. Furthermore, it is required to allow a
single node to be member of multiple RGs simultaneously.
5. ICC LDP Protocol extension Specification
To address the requirements identified in the previous section, ICCP
is modeled to comprise of three layers:
-i. Application Layer: This provides the interface to the
various redundancy applications that make use of the
services of ICCP. ICCP is concerned with defining common
connection management procedures and the formats of the
messages exchanged at this layer; however, beyond that, it
does not impose any restrictions on the procedures or
state-machines of the clients, as these are deemed
application-specific and lie outside the scope of ICCP.
This guarantees implementation inter-operability without
placing any unnecessary constraints on internal design
specifics.
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-ii. Inter Chassis Communication (ICC) Layer: This layer
implements the common set of services which ICCP offers to
the client applications. It handles protocol versioning, RG
membership, PE node identification and ICCP connection
management.
-iii. Transport Layer: This layer provides the actual ICCP message
transport. It is responsible for addressing, route
resolution, flow-control, reliable and in-order message
delivery, connectivity resiliency/redundancy and finally PE
node failure detection. The Transport layer may differ
depending on the Physical Layer of the inter-connect.
5.1. LDP ICC capability advertisement
When an RG is enabled on a particular PE, the capability of
supporting ICCP must be advertised to all LDP peers. This is achieved
by using the methods in [LDP-CAP] and advertising the ICCP LDP
capability TLV. If an LDP peer supports the dynamic capability
advertisement, this can be done by sending a new capability message
with the S bit set for the ICCP capability TLV when the first RG is
enabled on the PE. If the peer does not support dynamic capability
advertisement, then the ICCP TLV MUST be included in the LDP
initialization procedures in the capability parameter [LDP-CAP].
5.2. RG Membership Management
ICCP defines a mechanism that enables PE nodes to manage their RG
membership. When a PE is configured to be a member of an RG, it will
first advertise the ICCP capability to its peers. Subsequently the PE
sends an RG Connect message to the peers that have also advertised
ICCP capability. The PE then waits for the peers to send their own RG
Connect message, if they haven't already. For a given RG, the ICCP
connection between two devices is considered to be operational only
when both have sent and received ICCP RG Connect messages for that
RG.
If a PE that has sent an particular RG Connect message doesn't
receive a corresponding RG Connect from a destination it will simply
wait indefinitely for the corresponding RG Connect message. The RG
will not become operational until the corresponding RG Connect
Message has been received. If a PE that has sent an RG Connect
message receives a Notification message with a NAK, it will stop
attempting to bring up the ICCP connection immediately. A device MAY
send a NAK for an RG Connect message if it is not a member of the RG,
or if the maximum number of ICCP connections has been exceeded.
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A PE sends an RG Disconnect message to tear down the ICCP connection
for a given RG. This is a unilateral operation and doesn't require
any acknowledgement from the other PEs. Note that the ICCP connection
for an RG should be operational before any client application can
make use of ICCP services in that RG.
5.3. Application Connection Management
ICCP provides a common procedure by which applications on one PE can
connect to their counterparts on another PE, for purpose of inter-
chassis communication in the context of a given RG. The prerequisite
for establishing an application connection is to have an operational
ICCP RG connection between the two endpoints. It is assumed that the
association of applications with RGs is known apriori, e.g. by means
of device configuration. ICCP then sends Application Connect
messages, on behalf of each client application, to each remote PE
within the RG. The client may piggyback application-specific
information in that Connect message, which for example can be used to
negotiate parameters or attributes prior to bringing up the actual
application connection. The procedures for bringing up the
application connection are similar to those of the ICCP connection:
An application connection between two nodes is up only when both
nodes have sent and received Application Connect Messages. A PE can
send a Notification Message to NAK the Application Connect message if
the application doesn't exist or is not configured for that RG, or if
the protocol version is not compatible. When a PE receives such a NAK
notification, it should stop attempting to bring up the application
connection.
When an application is stopped on a device or it is no longer
associated with an RG, it should signal ICCP to trigger sending an
Application Disconnect message. This is a unilateral notification to
the other PEs within an RG, and as such doesn't trigger any response.
5.4. Application Data Transfer
When an application has information to transfer over ICCP it triggers
the transmission of an Application Data message. ICCP guarantees in-
order and loss-less delivery of data. An application may NAK a
message or a set of one or more TLVs within a message by using the
Notification Message with NAK TLV. Furthermore, an application may
implement an ACK mechanism, if deemed required, by defining an
application-specific TLV to be transported in an Application Data
message.
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6. ICCP PE Node Failure Detection Mechanism
ICCP provides its client applications a notification when a remote PE
that is member of the RG fails. This is used by the client
applications to trigger failover according to the procedures of the
employed redundancy protocol on the AC and PW. To that end, ICCP does
not define its own KeepAlive mechanism for purpose of monitoring the
health of remote PE nodes, but rather reuses existing fault detection
mechanisms. The following mechanisms may be used by ICCP to detect PE
node failure:
+ Loss of LDP Session
Loss of the LDP session with a PE in an RG can be used to
indicate to the local device that the remote PE is down. This can
be, for example, due to the TCP connection being reset. This
requires that the transport path for ICCP (and the underlying LDP
session) is protected by some Layer 2 or Layer 3 resiliency
mechanism.
+ BFD
Run a BFD session [BFD] between the PEs that are members of a
given RG, and use that to detect PE node failure. This assumes
that resiliency mechanisms are in place to protect connectivity
to the remote PE nodes, and hence loss of BFD periodic messages
from a given PE node can only mean that the node itself has
failed.
+ IP Reachability Monitoring
It is possible for a PE to monitor IP layer connectivity to other
members of an RG that are participating in IGP/BGP. When
connectivity to a given PE is lost, the local PE interprets that
to mean loss of the remote PE node. This assumes that resiliency
mechanisms are in place to protect the route to the remote PE
nodes, and hence loss of IP reachability to a given node can only
mean that the node itself has failed.
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7. ICCP Message Formats
This section defines the messages exchanged at the Application and
ICC layers.
7.1. Encoding ICC into LDP messages
ICCP requires reliable, in order, state-full message delivery, as
well as capability negotiation between PEs. The LDP protocol offers
all these features, and is already in wide use in the applications
that would also require the ICCP protocol extensions. For these
reasons, ICCP takes advantage of the already defined LDP protocol
infrastructure. [RFC5036] Section 3.5 defines a generic LDP message
structure. A new set of LDP message types is defined to communicate
the ICCP information. LDP message types in the range of 0x700 to
0x7ff will be used for ICC.
Message types are allocated by IANA, and requested in the IANA
section below.
7.1.1. ICC Header
Every ICCP message comprises of an ICC specific LDP Header followed
by an ICCP message. The format of the ICC Header is as follows:
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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| Message Type | Message Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Message ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ICC RG ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ +
| Mandatory Parameters |
~ ~
+ +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ +
| Optional Parameters |
~ ~
+ +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ U-bit
Unknown message bit. Upon receipt of an unknown message, if U is
clear (=0), a notification is returned to the message originator;
if U is set (=1), the unknown message is silently ignored. The
following sections which define messages specify a value for the
U-bit.
+ Message Type
Identifies the type of the ICCP message, must be in the range of
0x0700 to 0x07ff.
+ Message Length
Two octet integer specifying the total length of this message in
octets, excluding the U-bit, Message Type and Length fields.
+ Message ID
Four octet value used to identify this message. Used by the
sending PE to facilitate identifying RG Notification messages
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that may apply to this message. A PE sending an RG Notification
message in response to this message SHOULD include this Message
ID in the "NAK TLV" of the RG Notification message; see Section
"RG Notification Message".
+ ICC RG ID
Four octects unsigned integer designating the Redundancy Group
which the sending device is member of. RG ID value 0x00000000 is
reserved by the protocol.
+ Mandatory Parameters
Variable length set of required message parameters. Some
messages have no required parameters.
For messages that have required parameters, the required
parameters MUST appear in the order specified by the individual
message specifications in the sections that follow.
+ Optional Parameters
Variable length set of optional message parameters. Many
messages have no optional parameters.
For messages that have optional parameters, the optional
parameters may appear in any order.
7.1.2. Message Encoding
The generic format of an ICC parameter is:
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 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| TLV(s) |
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ U-bit
Unknown TLV bit. Upon receipt of an unknown TLV, if U is clear
(=0), a notification MUST be returned to the message originator
and the entire message MUST be ignored; if U is set (=1), the
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unknown TLV MUST be silently ignored and the rest of the message
processed as if the unknown TLV did not exist. The sections
following that define TLVs specify a value for the U-bit.
+ F-bit
Forward unknown TLV bit. This bit applies only when the U-bit is
set and the LDP message containing the unknown TLV is to be
forwarded. If F is clear (=0), the unknown TLV is not forwarded
with the containing message; if F is set (=1), the unknown TLV is
forwarded with the containing message. The sections following
that define TLVs specify a value for the F-bit. By setting both
the U- and F-bits, a TLV can be propagated as opaque data through
nodes that do not recognize the TLV.
+ Type
Fourteen bits indicating the parameter type.
+ Length
Length of the TLV in octets excluding the U-bit, F-bit, Type, and
Length fields.
+ TLV(s): A set of 0 or more TLVs, that vary according to the
message type.
7.2. RG Connect Message
The RG Connect Message is used to establish ICCP connection in
addition to individual Application connections between PEs in an RG:
an RG Connect message with no "Application-specific connect TLVs"
signals establishment of the base ICCP connection. RG Connect
messages with appropriate "Application-specific connect TLVs" signal
the establishment of Application connections, in addition to the base
ICCP connection (if not already established). A PE sends an RG
Connect Message to declare its membership in a Redundancy Group. One
such message should be sent to each PE that is member of the same RG.
The set of PEs to which RG Connect Messages should be transmitted is
known via configuration or an auto-discovery mechanism that is
outside the scope of this specification. If a device is member of
multiple RGs, it must send separate RG Connect Messages for each RG
even if the receiving device(s) happen to be the same.
The format of the RG Connect Message is as follows:
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-i. ICC header with Message type = "RG Connect Message" (0x0700)
-ii. "Sender Name TLV"
-iii. "Application specific connect TLV"
The currently defined Application-specific connect TLVs are:
+ PW Redundancy Connect TLV
The details of these TLVs are discussed in the "Application TLVs"
section.
The RG Connect message can contain zero, one or more Application-
specific connect TLVs. Multiple application connect TLVs can be sent
in a single message, or multiple messages can be sent containing
different application connect TLVs, but no application connect TLV
can be sent more than once.
7.2.1. Sender Name TLV
A TLV that carries the hostname of the sender encoded in UTF-8. This
is used primarily for purpose of management of the RG and easing
network operations. The specific format is shown below:
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 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sender Name |
+ +-+-+-+-+-+-+-+-+-+
~ ~
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ U=F=0
+ Type set to "ICC sender name" Parameter type (from ICC parameter
name space).
+ Length
Length of the TLV in octets excluding the U-bit, F-bit, Type, and
Length fields.
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+ Sender Name
Hostname of sending device encoded in UTF-8, and SHOULD not
exceed 80 characters.
7.3. RG Disconnect Message
The RG Disconnect Message serves dual-purpose: to signal that a
particular Application connection is being closed within an RG, or
that the ICCP connection itself is being disconnected because the PE
wishes to leave the RG. The format of this message is:
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| Message Type=0x0701 | Message Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Message ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ICC RG ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ICCP Status Code |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Optional Application-specific Disconnect TLVs |
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Optional Parameter TLVs |
+ +
| |
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ U-bit
U=0
+ Message Type
The message type for RG Disconnect Message is set to (0x0701)
+ Length
Length of the TLV in octets excluding the U-bit, Message Type,
and Message Length fields.
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+ Message ID
Defined in the "ICC Header" section above.
+ ICC RG ID
Defined in the "ICC Header" section above.
+ ICCP Status Code
A status code that reflects the reason for the disconnect
message. Allowed values are "RG Removed" and "Application
Removed from RG".
+ Optional Application-specific Disconnect TLVs
Zero, one or more Application-specific Disconnect TLVs which are
defined later in the document. If the RG Disconnect message has a
status code of "RG Removed", then it should not contain any
Application-specific Disconnect TLVs, as the sending PE is
signaling that it has left the RG and, thus, is disconnecting the
entire ICCP connection, with all associated client application
connections. If the message has a status code of "Application
Removed from RG", then it should contain one or more
Application-specific Disconnect TLVs, as the sending PE is only
tearing down the connection for the specified applications. Other
applications, and the base ICCP connection are not to be
affected.
+ Optional Parameter TLVs
None are defined for this message in this document.
7.4. RG Notification Message
A PE sends an RG Notification Message to indicate one of the
following: to reject an ICCP connection, to reject an application
connection, to NAK an entire message or to NAK one or more TLV(s)
within a message. The Notification message can only be sent to a PE
that is already part of an RG.
The format of the Notification Message is:
-i. ICC header with Message type = "RG Notification Message"
(0x0702)
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-ii. Notification Message TLVs.
The currently defined Notification message TLVs are:
-i. Sender Name TLV
-ii. NAK TLV.
7.4.1. Notification Message TLVs
The Sender Name TLV uses the same format as in the RG Connect
message, and was described above.
The NAK TLV is defined 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=0x0002 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ICCP Status Code |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Rejected Message ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Optional Rejected TLV(s) |
+ +
| |
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ U,F Bits
both U and F are set to 0.
+ Type
set to "NAK TLV" (0x0002)
+ Length
Length of the TLV in octets excluding the U-bit, F-bit, Type, and
Length fields.
+ ICCP Status Code
A status code the reflects the reason for the NAK TLV. Allowed
values are:
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-i. Unknown RG (0x00010001)
This code is used to reject a new incoming ICCP
connection for an RG that is not configured on the local
PE. When this code is used, the Rejected Message ID
field must contain the message ID of the rejected "RG
Connect" message.
-ii. ICCP Connection Count Exceeded (0x00010002)
This is used to reject a new incoming ICCP connection
that would cause the local PE's ICCP connection count to
exceed its capabilities. When this code is used, the
Rejected Message ID field must contain the message ID of
the rejected "RG Connect" message.
-iii. Application Connection Count Exceeded (0x00010003)
This is used to reject a new incoming application
connection that would cause the local PE's ICCP
connection count to exceed its capabilities. When this
code is used, the Rejected Message ID field must contain
the message ID of the rejected "RG Connect" message and
the corresponding Application Connect TLV must be
included in the "Optional Rejected TLV".
-iv. Application not in RG (0x00010004)
This is used to reject a new incoming application
connection when the local PE doesn't support the
application, or the application is not configured in the
RG. When this code is used, the Rejected Message ID
field must contain the message ID of the rejected "RG
Connect" message and the corresponding Application
Connect TLV must be included in the "Optional Rejected
TLV".
-v. Incompatible Protocol Version (0x00010005)
This is used to reject a new incoming application
connection when the local PE has an incompatible version
of the application. When this code is used, the Rejected
Message ID field must contain the message ID of the
rejected "RG Connect" message and the corresponding
Application Connect TLV must be included in the
"Optional Rejected TLV".
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-vi. Rejected Message (0x00010006)
This is used to reject an RG Application Data message,
or one or more TLV(s) within the message. When this
code is used, the Rejected Message ID field must contain
the message ID of the rejected "RG Application Data"
message.
-vii. ICCP Administratively Disabled (0x00010007)
This is used to reject any ICCP messages from a peer
from which the PE is not allowed to exchenge ICCP
messages due to local administrative policy.
+ Rejected Message ID If non-zero, 32-bit value that identifies
the peer message to which the NAK TLV refers. If zero, no
specific peer message is being identified.
+ Optional Rejected TLV(s)
A set of one or more TLVs that were rejected. If the entire
last message received is rejected, no TLVs will be present.
However, if only specific TLVs were rejected then those TLVs
MUST be echoed in this field.
7.5. RG Application Data Message
The RG Application Data Message is used to transport application data
between PEs within an RG. A single message can be used to carry data
from multiple applications, as long as all these applications are
part of the same RG. Such multiplexing is possible because the
transported TLVs are application specific which allows for
identifying the target application for each TLV at the receiving
side. The format of the Application Data Message is:
-i. ICC header with Message type = "RG Application Data Message"
(0x703)
-ii. "Application specific TLVs"
The details of these TLVs are discussed in the "Application TLVs"
section.
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7.6. Application TLVs
7.6.1. Pseudowire Redundancy (PW-RED) Application TLVs
This section discusses the ICCP TLVs for the Pseudowire Redundancy
application.
7.6.1.1. PW-RED Connect TLV
This TLV is included in the RG Connect message to signal the
establishment of PW-RED 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=0x0010 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Protocol Version | Optional Sub-TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +
~ ~
| |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ U and F Bits
Both are set to 0.
+ Type
set to 0x0010 for "PW-RED Connect TLV"
+ Length
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.
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+ Optional Sub-TLVs
There are no optional Sub-TLVs defined for this version of the
protocol.
7.6.1.2. PW-RED Disconnect TLV
This TLV is used in a RG Disconnect Message to indicate that the
connection for the PW-RED 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=0x0011 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Optional Sub-TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ U and F Bits
Both are set to 0.
+ Type
set to 0x0011 for "PW-RED Disconnect TLV"
+ Length
Length of the TLV in octets excluding the U-bit, F-bit, Type, and
Length fields.
+ Optional Sub-TLVs
There are no optional Sub-TLVs defined for this version of the
protocol.
7.6.1.3. PW-RED Config TLV
The PW-RED Config TLV is used in RG Application Data message and is
composed of the following TLVs in the following order:
-i. Service Name TLV
-ii. PW ID TLV or Generalized PW ID TLV
In the PW-RED Config TLV the U and F Bits are both are set to 0, and
the TLV type is set to 0x0012.
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7.6.1.4. Service Name 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 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Service Name |
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ U and F Bits
Both are set to 0.
+ Type
set to 0x0013 for "Service Name TLV"
+ Length
Length of the TLV in octets excluding the U-bit, F-bit, Type, and
Length fields.
+ Service Name
The name of the L2VPN service instance encoded in UTF-8 format
and up to 80 character in length.
7.6.1.5. PW ID TLV
This TLV is used to communicate the configuration of PWs for VPWS.
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 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Peer ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Group ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| PW ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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+ U and F Bits
Both are set to 0.
+ Type
set to 0x0014 for "PW ID TLV"
+ Length
Length of the TLV in octets excluding the U-bit, F-bit, Type, and
Length fields.
+ Peer ID
Four octet LDP Router ID of the peer at the far end of the PW.
+ Group ID
Same as Group ID in [PWE3-LDP] section 5.2.
+ PW ID
Same as PW ID in [PWE3-LDP] section 5.2.
7.6.1.6. Generalized PW ID TLV
This TLV is used to communicate the configuration of PWs for VPLS.
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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 = 0x0015 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| AGI Type | Length | Value |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ AGI Value (contd.) ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| AII Type | Length | Value |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ SAII Value (contd.) ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| AII Type | Length | Value |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ TAII Value (contd.) ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ U and F bits
both set to 0.
+ Type
set to 0x0015
+ Length
Length of the TLV in octets excluding the U-bit, F-bit, Type, and
Length fields.
+ AGI, AII, SAII and TAII
defined in [RFC4447] section 5.3.2.
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8. LDP Capability Negotiation
As requited in [LDP-CAP] the following TLV is defined to indicate the
ICCP capability:
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| TLV Code Point=0x405 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|S| Reserved | Reserved | VER/Maj | Ver/Min |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
where:
- U-bit
SHOULD be 1 (ignore if not understood).
+ F-bit
SHOULD be 0 (don't forward if not understood).
+ TLV Code Point
The TLV type, which identifies a specific capability. For the
ICCP code point is requested in the IANA allocation section
below.
+ S-bit The State Bit indicates whether the sender is advertising
or withdrawing the ICCP capability. The State bit is used as
follows:
1 - The TLV is advertising the capability specified by the
TLV Code Point.
0 - The TLV is withdrawing the capability specified by the
TLV Code Point.
+ Ver/Maj
The major version revision of the ICCP protocol, this document
specifies 1.0. This field is then set to 1
+ Ver/Min
The minor version revision of the ICCP protocol, this document
specifies 1.0. This field is then set to 0
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ICCP capability is advertised to a LDP peer if there is at least one
RG enabled on the local PE.
9. Client Applications
9.1. Pseudowire Redundancy Application Procedures
This section defines the procedures for the Pseudowire Redundancy
(PW-RED) Application.
9.1.1. Initial Setup
When an RG is configured on a system and multi-chassis pseudowire
redundancy is enabled in that RG, the PW-RED application should send
an "RG Connect" message with "PW-RED Connect TLV" to each PE that is
member of the same RG. When the system receives similar "RG Connect"
messages from a PE, the two devices can start exchanging "RG
Application Data" messages for the PW-RED application.
If a system receives an "RG Connect" message with "PW-RED Connect
TLV" that has an incompatible Protocol Version, it should reply with
"RG Notification" message with "Incompatible Protocol Version" status
code and the rejected "PW-RED Connect TLV".
When the PW-RED application is disabled on the device, or the RG is
de-configured, the system should send an "RG Disconnect" message with
"PW-RED Disconnect TLV".
9.1.2. Pseudowire Configuration
A system should advertise its local PW configuration to other PEs
that are members of the same RG. This allows the PEs to build a view
of the redundant nodes and pseudowires that are protecting the same
service instances. The advertisement should be initiated when the
PW-RED application connection first comes up, as well as upon any
subsequent PW configuration change. To that end, the system should
send "RG Application Data" messages with "PW-RED Config TLV". It is
possible to send configuration information for multiple PWs in a
single "RG Application Data" message.
The "Service Name TLV" is used on the receiving system for the
purpose of associating PW information advertised by some PE with the
corresponding AC information received over ICCP from that PE's AC
redundancy application. The Service Name has a global context in an
RG, so redundant PWs for the same service on disparate member PEs
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should share the same Service Name, in order to be correlated.
9.1.3. Pseudowire Status Synchronization
On a given PE, the forwarding status of the PW (Active or Standby) is
derived from the state of the associated AC(s). This simplifies the
operation of the multi-chassis redundancy solution (Figure 1) and
eliminates the possibility of deadlock conditions between the AC and
PW redundancy mechanisms. The rules by which the PW state is derived
from the AC state are as follows:
+ VPWS
For VPWS, there's a single AC per service instance. If the AC is
Active, then the PW status should be Active. If the AC is
Standby, then the PW status should be Standby.
+ VPLS
For VPLS, there could be multiple ACs per service instance (i.e.
VFI). If AT LEAST ONE AC is Active, then the PW status should be
Active. If ALL ACs are Standby, then the PW status should be
Standby.
The PW-RED application does not synchronize PW status across chassis,
per se. Rather, the AC Redundancy application should synchronize AC
status between chassis, in order to determine which AC (and
subsequently which PE) is Active or Standby for a given service. When
that is determined, each PE will then adjust its local PWs state
according to the rules described above.
9.1.4. PE Node Failure
When a PE node detects that a remote PE, that is member of the same
RG, has gone down, the local PE examines if it has redundant PWs for
the affected services. If the local PE has the highest priority
(after the failed PE) then it becomes the active node for the
services in question, and subsequently activates its associated PWs.
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9.2. Attachment Circuit Redundancy Application Procedures
9.2.1. Common AC Procedures
This section describes generic procedures for AC Redundancy
applications, independent of the type of the AC (ATM, FR or
Ethernet).
9.2.1.1. AC Failure
When the AC Redundancy mechanism on the Active PE detects a failure
of the AC, it should send an ICCP Application Data message to inform
the redundant PEs of the need to take over. The AC failures can be
categorized into the following scenarios:
+ Failure of CE interface connecting to PE
+ Failure of CE uplink to PE
+ Failure of PE interface connecting to CE
9.2.1.2. PE Node Failure
When a PE node detects that a remote PE, that is member of the same
RG, has gone down, the local PE examines if it has redundant ACs for
the affected services. If the local PE has the highest priority
(after the failed PE) then it becomes the active node for the
services in question, and subsequently activates its associated ACs.
9.2.1.3. PE Isolation
When a PE node detects that is has been isolated from the core
network (i.e. all core facing interfaces/links are not operational),
then it should instruct its AC Redundancy mechanism to change the
status of any active ACs to Standby. The AC Redundancy application
should then send ICCP Application Data messages in order to trigger
failover to a standby PE.
9.2.2. ATM AC Procedures
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9.2.3. Frame Relay AC Procedures
9.2.4. Ethernet AC Procedures
10. Security Considerations
The security considerations described in [RFC5036] and [RFC4447] that
apply to the base LDP specification, and to the PW LDP control
protocol extensions apply to the capability mechanism described in
this document.
The ICCP protocol is not intended to be applicable when the
redundancy group spans PE in different administrative domains.
Furthermore, implementations MUST provide a mechanism to select to
which LDP peers the ICCP capability will be advertised, and from wich
LDP peers the ICCP messages will be accepted.
11. IANA Considerations
11.1. MESSAGE TYPE NAME SPACE
This document uses several new LDP message types, IANA already
maintains a registry of name "MESSAGE TYPE NAME SPACE" defined by
[RFC5036]. The following values are suggested for assignment:
Message type Description
0x0700 RG Connect Message
0x0701 RG Disconnect Message
0x0702 RG Notification Message
0x0703 RG Application Data Message
11.2. TLV TYPE NAME SPACE
This document use a new LDP TLV type, IANA already maintains a
registry of name "TLV TYPE NAME SPACE" defined by [RFC5036]. The
following value is suggested for assignment:
TLV Type Description
0x405ICCP capability TLV.
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11.3. ICC RG Parameter Type Space
IANA needs to set up a registry of "ICC RG parameter type". These are
14-bit values. Parameter Type values 1 through 0x000F are specified
in this document, Parameter Type values 0x0010 through 0x1FFF are to
be assigned by IANA, using the "Expert Review" policy defined in
[RFC2434]. Parameter Type values 0x2000 through 0x2FFF, 0x3FFF, and 0
are to be allocated using the IETF consensus policy defined in
[RFC2434]. Parameter Type values 0x3000 through 0x3FFE are reserved
for vendor proprietary extensions and are to be assigned by IANA,
using the "First Come First Served" policy defined in [RFC2434]. A
Parameter Type description is required for any assignment from this
registry. Additionally, for the vendor proprietary extensions range a
citation of a person or company name is also required. A document
reference should also be provided.
Initial ICC RG parameter type space value allocations are specified
below:
Parameter Type Description Reference
-------------- --------------------------------- ---------
0x0001 ICC sender name [RFCxxxx]
0x0002 NAK TLV [RFCxxxx]
0x0010 PW-RED Connect TLV [RFCxxxx]
0x0011 PW-RED Disconnect TLV [RFCxxxx]
0x0012 PW-RED Config TLV [RFCxxxx]
0x0013 Service Name TLV [RFCxxxx]
0x0014 PW ID TLV [RFCxxxx]
0x0015 Generalized PW ID TLV [RFCxxxx]
11.4. STATUS CODE NAME SPACE
This document use several new Status codes, IANA already maintains a
registry of name "STATUS CODE NAME SPACE" defined by [RFC5036]. The
following values is suggested for assignment: The "E" column is the
required setting of the Status Code E-bit.
Range/Value E Description Reference
------------- ----- ---------------------- ---------
0x00010001 0 Unknown ICCP RG
0x00010002 0 ICCP Connection Count Exceeded
0x00010003 0 ICCP Application Connection
Count Exceeded
0x00010004 0 ICCP Application not in RG
0x00010005 0 Incompatible ICCP Protocol Version
0x00010006 0 ICCP Rejected Message
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0x00010007 0 ICCP Administratively Disabled
0x00010010 0 ICCP RG Removed
0x00010011 0 ICCP Application Removed from RG
12. Full Copyright Statement
Copyright (C) The IETF Trust (2008).
This document is subject to the rights, licenses and restrictions
contained in BCP 78, and except as set forth therein, the authors
retain all their rights.
This document and the information contained herein are provided on an
"AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE IETF TRUST AND
THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS
OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF
THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
13. Intellectual Property Statement
The IETF takes no position regarding the validity or scope of any
Intellectual Property Rights or other rights that might be claimed to
pertain to the implementation or use of the technology described in
this document or the extent to which any license under such rights
might or might not be available; nor does it represent that it has
made any independent effort to identify any such rights. Information
on the procedures with respect to rights in RFC documents can be
found in BCP 78 and BCP 79.
Copies of IPR disclosures made to the IETF Secretariat and any
assurances of licenses to be made available, or the result of an
attempt made to obtain a general license or permission for the use of
such proprietary rights by implementers or users of this
specification can be obtained from the IETF on-line IPR repository at
http://www.ietf.org/ipr.
The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary
rights that may cover technology that may be required to implement
this standard. Please address the information to the IETF at ietf-
ipr@ietf.org.
Martini, et al. [Page 35]
Internet Draft draft-martini-pwe3-iccp-00.txt June 2008
14. Normative References
[RFC5036] L. Andersson et al, "LDP Specification", RFC 5036,
October 2007.
[LDP-CAP] "LDP Capabilities", draft-ietf-mpls-ldp-capabilities-02.txt
April 2008, ( Work in Progress )
[PWE3-LDP] L. Martini et al, "Pseudowire Setup and Maintenance
Using the Label Distribution Protocol", RFC 4447, April 2006.
[IEEE-802.3] IEEE Std. 802.3-2005, "Part 3: Carrier Sense Multiple
Access with Collision Detection (CSMA/CD) Access Method and
Physical Layer Specifications", IEEE Computer Society, December
2005.
15. Informative References
none
16. Author Information
Luca Martini
Cisco Systems, Inc.
9155 East Nichols Avenue, Suite 400
Englewood, CO, 80112
e-mail: lmartini@cisco.com
Samer Salam
Cisco Systems, Inc.
595 Burrard Street, Suite 2123
Vancouver, BC V7X 1J1
e-mail: ssalam@cisco.com
Ali Sajassi
Cisco Systems, Inc.
170 West Tasman Drive
San Jose, CA 95134
e-mail: sajassi@cisco.com
Martini, et al. [Page 36]
Internet Draft draft-martini-pwe3-iccp-00.txt June 2008
Satoru Matsushima
Softbank Telecom
1-9-1, Higashi-Shinbashi, Minato-ku
Tokyo 105-7313, JAPAN
E-mail: satoru.matsushima@tm.softbank.co.jp
Thomas D. Nadeau
BT
BT Centre
81 Newgate Street
London, EC1A 7AJ
United Kingdom
E-mail: tom.nadeau@bt.com
Martini, et al. [Page 37]
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