Alcatel-Lucent 7210 SAS M User Manual page 171

These two parameters can be configured on a system in the config>router>rsvp context.
Refresh summary consists of sending a summary refresh messages containing message_id list
objects.
The fields of the message_id list object are populated with the values from the message_identifier
field in the message_id object of a previously sent individual path or resv message. The summary
refresh message is sent per refresh regular interval. The interval is configured by the user using the
refresh-time command in the config>router>rsvp context. The receiver checks each message_id
object against the saved path and resv states,if a match is found the state is updated. If any
message_identifier field does not match,the node sends a message_id_nack object to the originator of
the message.
The above capabilities are collectively referred to as "Refresh Overhead Reduction Extensions".
When refresh-reduction is enabled on an RSVP interface, the node sets a "refresh-reduction-capable"
bit in the flag field of the common RSVP header. If both peers on a RSVP interface set the "refresh-
reduction-capable" bit, all the refresh overhead reduction extensions can be implemented. The node
monitors the bit in all the RSVP messages received from the peer. The router stops sending summary
refresh messages once the bit is cleared ,the node does not send summary refresh messages if the bit
is not set by the peer.
A node (with refresh reduction, reliable message delivery enabled) attempts to perform reliable
message delivery even if the "refresh-reduction-capable" bit is not set by the peer. If the peer does not
support the message_id object, it returns an error message "unknown object class".The node re-
transmits the RSVP message without the message_id object and adopts the same message handling
method for all future messages sent to the peer.
The no form of the command reverts to the default value.
Default no refresh-reduction
reliable-delivery
Syntax [no] reliable-delivery
Context config>router>rsvp>interface>refresh-reduction
Description
This command enables reliable delivery of RSVP messages over the RSVP interface. When refresh-
reduction is enabled on an interface and reliable-delivery is disabled, then the router will send a
message_id and not set ACK desired in the RSVP messages over the interface. Thus
not expect an ACK and but will accept it if received. The node will also accept message ID and reply
with an ACK when requested. In this case, if the neighbor set the "refresh-reduction-capable" bit in
the flags field of the common RSVP header, the node will enter summary refresh for a specific
message_id it sent regardless if it received an ACK or not to this message from the neighbor.
Finally, when 'reliable-delivery' option is enabled on any interface, RSVP message pacing is disabled
on all RSVP interfaces of the system, for example, the user cannot enable the msg-pacing option in
the config>router>rsvp context, and error message is returned in CLI. Conversely, when the msg-
pacing option is enabled, the user cannot enable the reliable delivery option on any interface on this
system. An error message will also generated in CLI after such an attempt.
7210 SAS M, T, X, R6, Mxp MPLS Configuration Guide
• The updated backoff interval exceeds the regular refresh interval.
• The number of retransmissions reaches the value of the rapid-retry-limit parameter, whichever
comes first.
MPLS and RSVP
7210 SAS
does
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