681
Configuring IP Multicast Routing
Information About Cisco’s Implementation of IP Multicast Routing
Figure 87
RPF Check
PIM uses both source trees and RP-rooted shared trees to forward datagrams (described in the
and
the
). The RPF check is performed differently for each:
If a PIM router or multilayer switch has a source-tree state (that is, an (S,G) entry is present in the multicast routing
table), it performs the RPF check against the IP address of the source of the multicast packet.
If a PIM router or multilayer switch has a shared-tree state (and no explicit source-tree state), it performs the RPF
check on the RP address (which is known when members join the group).
Sparse-mode PIM uses the RPF lookup function to decide where it needs to send joins and prunes:
(S,G) joins (which are source-tree states) are sent toward the source.
(*,G) joins (which are shared-tree states) are sent toward the RP.
Dense-mode PIM uses only source trees and uses RPF as previously described.
Information About Source-Specific Multicast
The Source-Specific Multicast (SSM) feature is an extension of IP multicast in which datagram traffic is forwarded to
receivers from only those multicast sources that the receivers have explicitly joined. For multicast groups configured for
SSM, only SSM distribution trees (no shared trees) are created.
SSM Components Overview
SSM is a datagram delivery model that best supports one-to-many applications, also known as broadcast applications.
SSM is a core networking technology for the Cisco implementation of IP multicast solutions targeted for audio and video
broadcast application environments. The switch supports these components that support the implementation of SSM:
Protocol independent multicast source-specific mode (PIM-SSM)
PIM-SSM is the routing protocol that supports the implementation of SSM and is derived from PIM sparse mode
(PIM-SM).
Internet Group Management Protocol version 3 (IGMPv3)
Network
Port
151.10.0.0/16
Gigabit Ethernet 0/1
198.14.32.0/32
Fast Ethernet 0/1
204.1.16.0/24
Fast Ethernet 0/2
Multicast
packet from
source 151.10.3.21
is forwarded.
Multicast
packet from
source 151.10.3.21
packet is discarded.
Gigabit Ethernet 0/1
Fast Ethernet 0/1
Fast Ethernet 0/2
Gigabit Ethernet 0/2
141002
Layer 3 switch
Summary of Contents for IE 4000
Page 12: ...8 Configuration Overview Default Settings After Initial Switch Configuration ...
Page 52: ...48 Configuring Interfaces Monitoring and Maintaining the Interfaces ...
Page 108: ...104 Configuring Switch Clusters Additional References ...
Page 128: ...124 Performing Switch Administration Additional References ...
Page 130: ...126 Configuring PTP ...
Page 140: ...136 Configuring CIP Additional References ...
Page 146: ...142 Configuring SDM Templates Configuration Examples for Configuring SDM Templates ...
Page 192: ...188 Configuring Switch Based Authentication Additional References ...
Page 244: ...240 Configuring IEEE 802 1x Port Based Authentication Additional References ...
Page 298: ...294 Configuring VLANs Additional References ...
Page 336: ...332 Configuring STP Additional References ...
Page 408: ...404 Configuring DHCP Additional References ...
Page 450: ...446 Configuring IGMP Snooping and MVR Additional References ...
Page 490: ...486 Configuring SPAN and RSPAN Additional References ...
Page 502: ...498 Configuring Layer 2 NAT ...
Page 770: ...766 Configuring IPv6 MLD Snooping Related Documents ...
Page 930: ...926 Configuring IP Unicast Routing Related Documents ...
Page 976: ...972 Configuring Cisco IOS IP SLAs Operations Additional References ...
Page 978: ...974 Dying Gasp ...
Page 990: ...986 Configuring Enhanced Object Tracking Monitoring Enhanced Object Tracking ...
Page 994: ...990 Configuring MODBUS TCP Displaying MODBUS TCP Information ...
Page 996: ...992 Ethernet CFM ...
Page 1066: ...1062 Using an SD Card SD Card Alarms ...