Alcatel-Lucent 7210 SAS M User Manual page 170

Interface Commands
The user must shutdown the RSVP interface before being able to change the implicit null
configuration option.
The no form of this command returns the RSVP interface to use the RSVP level configuration value.
Default
disable
Parameters
enable — This parameter enables the implicit null label.
disable — This parameter disables the implicit null label.
refresh-reduction
Syntax [no] refresh-reduction
Context config>router>rsvp>interface
Description This command enables the use of the RSVP overhead refresh reduction capabilities on this RSVP
interface.
The
reliable RSVP message delivery to its peer, and utilizes summary refresh messages to refresh the path
and resv states. Reliable message delivery must be explicitly enabled by the user after refresh
reduction is enabled.
The other two capabilities are immediately enabled.
A bundle message reduces the overall message handling load, it consists of a bundle header followed
by one or more bundle sub-messages. A bundle sub-message is any RSVP message other than a
bundle message. A 7210 node only processes the bundled RSVP messages received and does not
generate them.
When reliable message delivery is supported by both the node and its peer over the RSVP interface, a
RSVP message is sent with a message_id object. A message_id object can be added to any RSVP
message or it can be a sub-message of a bundled message.
If a node sets the ack_desired flag in the message_id object , the receiver acknowledges the receipt of
the RSVP message by piggy-backing a message_ack object in the next RSVP message it sends to the
node. Alternatively, an ACK message can also be used to send the message_ack object. In both cases,
more than one message_ack object can be included in the same message.
The 7210 supports only the use of ACK messages to send message_ack object , but it can also
process the received message_ack objects piggy-backed to hop-by-hop RSVP messages, such as path
and resv.
The 7210 sets the ack_desired flag only in non-refresh RSVP messages and in refresh messages
which contain new state information.
A retransmission mechanism based on an exponential backoff timer is supported to handle un-
acknowledged message_id objects. A RSVP message with the same message_id is re-transmitted at
an interval of 2 * rapid-retransmit-time. The rapid-retransmit-time is referred to as the rapid
retransmission interval and it should be lesser than the regular refresh interval configured in the
config>router>rsvp>refresh-time context.
Rapid retry limit indicates the maximum number of retransmissions allowed for unacknowledged
RSVP messages. The node stops the retransmission of unacknowledged RSVP messages when:
Page 170
Guide
7210 SAS
node accepts bundle RSVP messages from its peer over the interface, performs
7210 SAS M, T, X, R6, Mxp MPLS Configuration