Prefix Trees - Juniper JUNOSE 11.0.X IP SERVICES Configuration Manual

JUNOSe 11.0.x IP Services Configuration Guide
match ip next-hop
match ipv6 next-hop

Prefix Trees

A prefix tree is a nonsequential collection of permit and deny conditions that apply
to IP addresses. Like a prefix list, the prefix tree specifies a base IP address and a
length, the number of bits applied to the base to determine the network prefix. The
tested address is matched against the prefix. The prefix tree also enables route
summarization.
However, the prefix tree does not match addresses one by one in sequence against
the listed conditions. The router performs a binary search against the tree structure
of the entries. If the tested address is less than a particular entry, it branches one
way to another test pair; if it is greater than the entry, it branches the other way to
another mutually exclusive test pair. The router stops testing conditions when it finds
the best match. If no conditions match, the router rejects the address. An empty
prefix tree results in an automatic permit of the tested address.
The prefix tree provides a faster search method and matches the test address more
closely than either the access list or the prefix list.
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Prefix Trees
Use the no version to delete all address match clauses from a route map unless
you specify an access list or prefix list, in which case only the list match is
removed from the route map.
See match ipv6 address.
Use with the prefix-list keyword to match routes that have a next-hop router
address passed by the specified access lists, prefix lists, or prefix trees.
Example
host1(config-route-map)#match ip next-hop prefix-list abc
Use the no version to delete the match clause from a route map or a specified
value from the match clause.
See match ip next-hop.
Use to match any routes that have a next-hop router address passed by the
specified access list or prefix list.
Example
host1(config-route-map)#match ipv6 next-hop prefix-list next1
Use the no version to delete all next-hop match clauses from a route map unless
you specify an access list or prefix list, in which case the router removes only
the list match from the route map.
See match ipv6 next-hop.