Cooperative Route Filtering; Dynamic Capability Negotiation; Four-Octet As Numbers - Juniper JUNOSE 11.2.X BGP AND MPLS Configuration Manual

JunosE 11.2.x BGP and MPLS Configuration Guide
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NOTE: The graceful restart capability is controlled with the bgp graceful-restart and
neighbor graceful-restart commands rather than the neighbor capability command.
However, the no neighbor capability command will prevent negotiation of the graceful
restart capability.

Cooperative Route Filtering

The cooperative route filtering capability—also referred to as outbound route filtering
(ORF)—enables a BGP speaker to send an inbound route filter to a peer and have the
peer install it as an outbound filter on the remote end of the session.
You must specify both the type of inbound filter (ORF type) and the direction of ORF
capability. The router currently supports prefix-lists as the inbound filter sent by the BGP
speaker. The inbound filter sent by the BGP speaker can be a prefix list or a Cisco
proprietary prefix list. The BGP speaker must indicate whether it will send inbound filters
to peers, accept inbound filters from peers, or both. The router supports both standard
and Cisco-proprietary orf messages.

Dynamic Capability Negotiation

If both peers acknowledge support of dynamic capability negotiation, then at any
subsequent point after the session is established, either peer can send a capabilities
message to the other indicating a desire to negotiate another capability or to remove a
previously negotiated capability.
The data field of the capability message contains a list of all the capabilities that can be
dynamically negotiated. In earlier versions, now deprecated, the data field did not carry
this information. Use the dynamic-capability-negotiation keyword to include the list.
Use the deprecated-dynamic-capability-negotiation keyword to exclude sending the
list.
Nondynamic capability negotiation is supported for the cooperative route filtering,
four-octet AS numbers, deprecated dynamic capability negotiation, and dynamic
capability negotiation capabilities. Dynamic capability negotiation of these capabilities
is not supported.
If both sides of the connection advertise support for the new dynamic capability
negotiation capability, then the peers negotiate which capabilities are dynamic and which
are not.
If both sides of the connection advertise support only for the deprecated dynamic
capability negotiation, then the BGP speaker uses dynamic capability negotiation for all
capabilities that allow it without attempting to negotiate this with the peer.

Four-Octet AS Numbers

BGP speakers that support four-octet AS and sub-AS numbers are sometimes referred
to as " new" speakers. The four-octet AS numbers are employed by the AS-path and
aggregator attributes. " Old" speakers are those that do not support the four-octet
numbers.
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