CISCO IOS in a Nutshell

Name

ip multicast helper-map — interface

Synopsis

ip multicast helper-map group-address 
               broadcast-address 
               access-list
no ip multicast helper-map group-address 
               broadcast-address 
               access-list

ip multicast helper-map broadcast multicast-address 
               access-list
no ip multicast helper-map broadcast multicast-address 
               access-list
            

Configures

Multicast tunneling

Default

None

Description

Use this command to send broadcast packets through a multicast network that connects two or more broadcast-capable networks. At one multicast network, you convert the multicast packets to broadcast packets and send them through the broadcast network, which converts them back to multicast packets at the other end.

group-address

Multicast group whose traffic is to be converted to broadcast traffic.

broadcast

Specifies that the traffic is going to be converted from broadcast to multicast.

broadcast-address

When using the group-address parameter, this parameter specifies the IP address to which to send the broadcast traffic.

multicast-address

When using the broadcast option, this variable specifies the multicast address to which converted traffic is sent.

access-list

An extended access list that uses the UDP port number to control which broadcast packets will be converted.

Example

The following configuration converts multicast traffic for the multicast group 224.1.1.2 to broadcast traffic using the broadcast address 10.1.1.255 and UDP port 5000:

interface ethernet 0 ip multicast helper-map 224.1.1.2 10.1.1.255 101 ip pim dense-mode ...