R0106-HP MSR Router Series MPLS Command Reference(V7)

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[Sysname] interface gigabitethernet 2/1/1
[Sysname-GigabitEthernet2/1/1] rsvp reduction retransmit interval 1000
Related commands
• rsvp reduction retransmit increment
• rsvp reduction srefresh
rsvp reduction srefresh
Use rsvp reduction srefresh to enable summary refresh and reliable RSVP message delivery.
Use undo rsvp reduction srefresh to disable summary refresh and reliable RSVP message delivery.
Syntax
rsvp reduction srefresh [ reliability ]
undo rsvp reduction srefresh
Default
Summary refresh and reliable RSVP message delivery are disabled.
Views
Interface view
Predefined user roles
network-admin
Parameters
reliability: Enables reliable RSVP message delivery. If you do not specify this keyword, the command
enables only the summary refresh function.
Usage guidelines
RSVP sends Path and Resv messages with the same states and objects to maintain the path and
reservation states at a specific interval (configured by the refresh interval command). These messages
are collectively referred to as refresh messages. Refresh messages are used to synchronize the path and
reservation states on RSVP neighbors and to recover from lost RSVP messages.
When multiple RSVP sessions exist on a network, the periodically sent refresh messages can cause
network degradation. In this case, the refreshing interval of Path and Resv messages should not be too
short. However, delay sensitive applications want to recover from lost RSVP messages through the refresh
messages as soon as possible. In this case, the refreshing interval should not be too long. You can use the
summary refresh (Srefresh) and the reliable RSVP message delivery functions to find the appropriate
balance.
Srefresh is implemented by adding a Message_ID object to a Path or Resv message to uniquely identify
the message. To refresh Path and Resv states, RSVP does not need to send standard Path and Resv
messages. Instead, it can send a summary refresh message that carries a set of Message_ID objects that
identify the Path and Resv states to be refreshed. The Srefresh function reduces the number of refresh
messages on the network and speeds up the refresh message processing.
Reliable RSVP message delivery requires the peer device to acknowledge each RSVP message received
from the local device. If no acknowledgement is received, the local device retransmits the message.
To implement reliable RSVP message delivery, a node sends an RSVP message that includes a
Message_ID object in which the ACK_Desired flag is set. The receiver needs to confirm the delivery by