Well-known or reserved multicast addresses excluded from IP multicast filtering

Each multicast host group is identified by a single IP address in the range of 224.0.0.0 through 239.255.255.255. Specific groups of consecutive addresses in this range are termed "well-known" addresses and are reserved for predefined host groups. IGMP does not filter these addresses, so any packets the switch receives for such addresses are flooded out all ports assigned to the VLAN on which they were received (except the port on which the packets entered the VLAN.)

The following table lists the 32 well-known address groups (8192 total addresses) that IGMP does not filter on.

Table 5: IP multicast address groups excluded from IGMP filtering

Groups of consecutive addresses in the range of 224.0.0.X to 239.0.0.X1

Groups of consecutive addresses in the range of 224.128.0.X to 239.128.0.X 1

224.0.0.x

232.0.0.x

224.128.0.x

232.128.0.x

225.0.0.x

233.0.0.x

225.128.0.x

233.128.0.x

226.0.0.x

234.0.0.x

226.128.0.x

234.128.0.x

227.0.0.x

235.0.0.x

227.128.0.x

235.128.0.x

228.0.0.x

236.0.0.x

228.128.0.x

236.128.0.x

229.0.0.x

237.0.0.x

229.128.0.x

237.128.0.x

230.0.0.x

238.0.0.x

230.128.0.x

238.128.0.x

231.0.0.x

239.0.0.x

231.128.0.x

239.128.0.x

1 X is any value from 0 to 255.

NOTE:

With aliasing limitation associated with MAC mode, certain non reserved multicast IP addresses are displayed as "reserved" addresses.

For example: 225.0.0.x Multicast IP address is aliased to 224.0.0.x to be displayed as "reserved".