# Multicast Routing Table List

The multicast route table is populated by multicast static routes or routes learned through a multicast routing protocol. The NetScreen device uses the information from the multicast route table to forward multicast traffic. NetScreen devices maintain a multicast routing table for each routing protocol in a virtual router.

You can set the following options on a virtual router basis:

Multiple Incoming Interface: Permits multiple multicast routes for the same source and group.

Maximum Entries: Specifies the maximum number of multicast routes allowed in the multicast routing table.

MRoute Negative Cache: Creates negative multicast routes if the protocol that owns the interface on which the packet was received cannot create a forwarding multicast route. The NetScreen device drops packets when they need to go on a negative multicast route.

MRoute Negative Cache Timer: Specify the duration, in seconds, that the NetScreen device maintains the entries in the negative cache. The NetScreen device removes the entry in the negative cache when it receives information enabling it to create a forwarding multicast route entry.

## Viewing the Multicast Routing Table

The multicast route table provides a read-only summary of all multicast routes and displays information in the following columns:

Source IP: The IP address of the source that is transmitting the multicast traffic.

MGroup: The IP address of the multicast group to which the source is transmitting the multicast traffic.

Incoming interface: The interface on which the traffic was received.

Outgoing Interface: The interface through which the NetScreen device sends the traffic downstream towards the receivers.

Translated MGroup: The IP address of the multicast group on the outgoing interface, if the NetScreen device translated the multicast group address.

Configure: Click Edit to modify a static multicast route. Click remove to remove a static multicast route.