3com 3031 Instruccion De Instalación

IP multicast policy routing is subsidiary and enhancement to the function that 
multicast forwards packets according to the routing table. It forwards multicast 
packets according to the policy the user specifies.

IP multicast policy routing is implemented by configuring the route-policy. The 
route-policy is an extension of unicast policy routing, described by a group of 

if-match

 and apply statements the user defines. The 

if-match

 clause defines the 

match rule, i.e., the filter conditions to be met to pass the current route-policy. It 
specifies when a multicast packet meets the match conditions the user defines, 
the multicast packet is not forwarded according to the usual process, but 
forwarded according to the action the user sets (described by the apply 
statement).

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route-policy

The policy of the IP multicast policy routing is implemented by configuring the 
route-policy. Multiple route-policies can be configured on a router. Each 
route-policy may contain multiple route-nodes.

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node

A node is a complete policy, which sets the conditions packets should match 
with the

 command and sets the forwarding actions that should be 

executed to packets meeting the match conditions with the 

 command. 

Each node contains at most one ACL used for defining the match conditions of 
packets, one ACL used for specifying the outgoing interface and one ACL used 
for specifying the next hop.

Multiple nodes with different conditions and actions can be configured in a 
route-policy. Different policy-nodes in each route-policy can be identified 
through an integer sequence-number.

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Match rule

Match conditions of multicast packets are described by the 

if-match

 clause 

and are set by configuring the standard or extended ACL (ranging from 1 to 
199).

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Forwarding actions of multicast packets

Forwarding actions of multicast packets are described by the APPLY clause 
including setting the outgoing interface and the next hop IP address. The 
output interface list is specified through an interface-based ACL (ranging from 
2000 to 3999). The next hop IP address list is specified through a standard ACL 
(ranging from 2000 to 2999).