Specifications

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conveniently strip all communities that start with specific Autonomous
System Numbers.
§ route filtering based on prefix and ASN - The policy engine can be used
to apply lists of prefixes and/or ASNs against a particular BGP peer for
filtering inbound announcements and similar filters can be applied to
outbound announcements towards a peer.
§ route reflection (server and client) - The Juniper BGP implementation
includes route reflection, both the server and client side (though the client
side is just a normal BGP speaker), and the server includes support for
hierarchical reflection
§ peer-group configuration for peers with the same routing policy - A set
of BGP peers that share the same or similar policy can be configured as a
group to speed up processing of the policy checks.
§ export default to external peer - The Juniper BGP implementation can
export a default route to an external peer, while not incorporating it into the
forwarding table.
§ support for well-known attribute values like "no-export" - The Juniper
BGP implementation supports the well-known no-export, no-advertise and
no-export-subconfed communities and automatically behaves appropriately
with respect to the associated prefix.
§ eBGP multi-hop and multi-path load sharing - Junos supports E-BGP
multi-hop peering sessions. The configuration of an E-BGP peer can include
specifying that it is more than one hop away. Multi-path load sharing for E-
BGP is the ability to select multiple EBGP paths as active and load balance
traffic across multiple EBGP or confederation peerings; it is supported
through E-BGP loopback peering sessions.
§ update routing policy without session reset. Junos stores all routes
received from a peer, even if all of those routes don’t pass policy. If a policy
configuration change is implemented such that previously rejected routes
should be accepted, the Mxxx can accept those routes without having to
reset the BGP session.
§ configurable peer keepalive and time-out values - The configuration
system allows these values to be set by the user.
§ iBGP group id (cluster id) - The configuration system allows this value to
be set by the user.
§ specification of update source IP address - The configuration system
allows this value to be set by the user. This allows for a routing architecture
where the end-points of I-BGP sessions are addresses not associated with
physical interfaces but instead are virtual interfaces which are routed with an
Internal Gateway Protocol (IGP) such as IS-IS.
§ export of MED, community and nexthop attributes - While the policy
engine allows the user to change the MED, community and next-hop
attributes when a prefix is sent to a peer, it also allows those attributes to be
passed unchanged.
§ conversion of internal metric to MED - The configuration for a BGP peer
can specify that the MULTI-EXIT-DISCRIMINATOR be set based on the IGP
metric for the next hop.
§ reset origin code - The policy configuration can include resetting the origin
code attribute associated with a prefix.
§ source BGP routes via configuration - The configuration system allows
the user to create static routes and then write policy such that the static route
is injected into BGP.
§ BGP session authentication - The Juniper BGP implementation allows the
underlying TCP connection to use the MD5 authentication option. This
feature is compliant with the IETF’s specification, and inter-operates with the
de facto standard of the behavior of Cisco’s implementation.
§ access to the full BGP table, BGP session statistics and, on a per-peer
basis, all (or specified subsets) prefixes announced & received (before
and after the application of inbound-filters) - The user interface contains
show commands that give the user access to all of this information. In
addition, the Juniper routing software includes a full implementation of the
BGP4 MIB for management with SNMP.
§ display prefixes based on regular-expressions (REGEX) containing as-
paths, community-values and flap dampening status - The command line
interface (CLI) contains show commands, which allow the user to display
prefixes by applying regular expressions to the AS-Path attributes of prefixes