User guide

14-2 E
XTREME
W
ARE
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OFTWARE
U
SER
G
UIDE
IP M
ULTICAST
R
OUTING
O
VERVIEW
IP multicast routing is a function that allows a single IP host to send a packet to a group
of IP hosts. This group of hosts can include devices that reside on the local network,
within a private network, or outside of the local network.
IP multicast routing consists of the following functions:
• A router that can forward IP multicast packets.
• A router-to-router multicast routing protocol (for example, Distance Vector Multicast
Routing Protocol (DVMRP) or Protocol Independent Multicast (PIM)).
• A method for the IP host to communicate its multicast group membership to a
router (for example, Internet Group Management Protocol (IGMP)).
You should configured IP unicast routing before you configure IP multicast
routing.
DVMRP O
VERVIEW
DVMRP is a distance vector protocol that is used to exchange routing and multicast
information between routers. Like RIP, DVMRP periodically sends the entire routing
table to its neighbors.
DVMRP has a mechanism that allows it to prune and graft multicast trees to reduce the
bandwidth consumed by IP multicast traffic.
PIM O
VERVIEW
The switch supports both dense mode and sparse mode operation. You can configure
dense mode or sparse mode on a per-interface basis. Once enabled, some interfaces can
run dense mode, while other run sparse mode.
You can run either DVMRP or PIM on the switch, but not both simultaneously.