Alcatel-Lucent 7450 Manual page 305

The above capabilities are referred to collectively as "refresh overhead reduction extensions". When
the refresh-reduction is enabled on an RSVP interface, the node indicates this to its peer by setting a
"refresh-reduction-capable" bit in the flags field of the common RSVP header. If both peers of an
RSVP interface set this bit, all the above three capabilities can be used. Furthermore, the node
monitors the settings of this bit in received RSVP messages from the peer on the interface. As soon as
this bit is cleared, the router stops sending summary refresh messages. If a peer did not set the
"refresh-reduction-capable" bit, a node does not attempt to send summary refresh messages.
However, if the peer did not set the "refresh-reduction-capable" bit, a node, with refresh reduction
enabled and reliable message delivery enabled, will still attempt to perform reliable message delivery
with this peer. If the peer does not support the message_id object, it returns an error message
"unknown object class". In this case, the node retransmits the RSVP message without the message_id
object and reverts to using this method for future messages destined to this peer. The RSVP Overhead
Refresh Reduction is supported with both RSVP P2P LSP path and the S2L path of an RSVP P2MP
LSP instance over the same RSVP instance.
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
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.
The no form of the command reverts to the default value.
Default no reliable-delivery
7450 ESS MPLS Guide
MPLS and RSVP
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does not
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