Cisco Systems C3850NM410G Multicast Mode Configuration

The videostream mode is a further enhancement of the preceding. Instead of sending the multicast as broadcast at

the lowest data rate, the access point converts the original multicast packet as unicast and sends it only to the

interested client at the highest available data rate. This works the same way as it works in today’s Cisco Unified

Wireless Network as the function is performed at the access point level.

The following commands enable wireless multicast on the Cisco Catalyst 3850 Switch:

Switch#conf t

Switch(config)#ip multicast-routing

Switch(config)#wireless multicast

Switch(config)#wireless broadcast

Switch(config)#Wireless multicast non-ip

Switch(config)#interface interface-id

Switch(config-if)# ip pim {dense-mode | Sparse-Mode | Sparse-dense-mode}

Switch(config)#vlan configuration <id>

Switch(config-vlan)#ipv6 nd suppress

Switch(config-vlan)#ipv6 snooping

Switch(config-vlan)#end

Switch#copy running-config startup-config

Irrespective of multicast routing being enabled, Internet Group Management Protocol (IGMP) snooping must be

enabled on the client VLAN for wireless clients to receive IP multicast traffic.

To enable multicast routing on a Cisco Catalyst 3850 Switch, the “ip multicast-routing” command is used. To send

multicast on wireless to all clients (interested in multicast or not), the “wireless-multicast” command is used.

“Wireless-broadcast” command enables broadcasting of packets on wireless data plane of switch.

To enable multicast flooding on wireless, the “wireless multicast non-ip” command can be used.

Multicast Mode Configuration

Wireless multicast packets are required to be sent to the access point as CAPWAP encapped packet in a unicast

tunnel or a multicast tunnel. When multicast mode is enabled, WCM creates a multicast CAPWAP tunnel in Cisco

IOS Software and converts the access point tunnels to multicast mode pointing to the multicast tunnel.

When an access point is in multicast mode, the multicast/broadcast packets to the client behind this access point

are sent to this access point in an outer multicast tunnel.

All the access points in the multicast mode must watch for the multicast group, which is specified while creating the

multicast tunnel. Following is a multicast mode configuration:

Switch# conf t

Switch(config)# ap capwap multicast <Multicast IP Address>