M
ULTICAST
R
OUTING
3-323
CLI
– This example shows that multicast forwarding is enabled. The
multicast routing table displays one entry for a multicast source routed by
DVMRP, and another source routed via PIM.
Configuring DVMRP
The Distance-Vector Multicast Routing Protocol (DVMRP) behaves
somewhat similarly to RIP. A router supporting DVMRP periodically
floods its attached networks to pass information about supported
multicast services along to new routers and hosts. Routers that receive a
DVMRP packet send a copy out to all paths (except the path back to the
origin). These routers then send a prune message back to the source to
stop a data stream if the router is attached to a LAN which does not want
to receive traffic from a particular multicast group. However, if a host
attached to this router issues an IGMP message indicating that it wants to
subscribe to the concerned multicast service, this router will use DVMRP
to build up a source-rooted multicast delivery tree that allows it to prevent
Console#show ip mroute
3-188
IP Multicast Forwarding is enabled.
IP Multicast Routing Table
Flags: P - Prune, F - Forwarding
(234.5.6.7, 10.1.0.0, 255.255.255.0)
Owner: DVMRP
Upstream Interface: vlan2
Upstream Router: 10.1.0.0
Downstream:
(234.5.6.8, 10.1.5.19, 255.255.255.255)
Owner: PIM-DM
Upstream Interface: vlan3
Upstream Router: 10.1.5.19
Downstream:
Console#
Summary of Contents for 8612XL3
Page 2: ......
Page 26: ...CONTENTS xxvi ...
Page 40: ...INTRODUCTION 1 14 ...
Page 69: ...BASIC CONFIGURATION 3 15 ...
Page 175: ...PORT CONFIGURATION 3 121 ...
Page 337: ...IP ROUTING 3 283 Web Click Routing Protocol RIP Statistics ...
Page 379: ...MULTICAST ROUTING 3 325 Command Usage ...
Page 396: ...CONFIGURING THE SWITCH 3 342 ...
Page 582: ...COMMAND LINE INTERFACE 4 186 ...
Page 806: ... 224 Command Mode Privileged Exec Example Console clear vrrp 1 interface 1 counters Console ...
Page 826: ... 6 ...
Page 828: ...TROUBLESHOOTING B 2 ...
Page 838: ...GLOSSARY Glossary 10 ...
Page 845: ......