685
Configuring IP Multicast Routing
Prerequisites
Figure 89
Shared Tree and Source Tree (Shortest-Path Tree)
If the data rate warrants, leaf routers (routers without any downstream connections) on the shared tree can use the data
distribution tree rooted at the source. This type of distribution tree is called a shortest-path tree or source tree. By default,
the software switches to a source tree upon receiving the first data packet from a source.
This process describes the move from a shared tree to a source tree:
1.
A receiver joins a group; leaf Router C sends a join message toward the RP.
2.
The RP puts a link to Router C in its outgoing interface list.
3.
A source sends data; Router A encapsulates the data in a register message and sends it to the RP.
4.
The RP forwards the data down the shared tree to Router C and sends a join message toward the source. At this
point, data might arrive twice at Router C, once encapsulated and once natively.
5.
When data arrives natively (unencapsulated) at the RP, it sends a register-stop message to Router A.
6.
By default, reception of the first data packet prompts Router C to send a join message toward the source.
7.
When Router C receives data on (S,G), it sends a prune message for the source up the shared tree.
8.
The RP deletes the link to Router C from the outgoing interface of (S,G). The RP triggers a prune message toward
the source.
Join and prune messages are sent for sources and RPs. They are sent hop-by-hop and are processed by each PIM
device along the path to the source or RP. Register and register-stop messages are not sent hop-by-hop. They are sent
by the designated router that is directly connected to a source and are received by the RP for the group.
Multiple sources sending to groups use the shared tree.
You can configure the PIM device to stay on the shared tree. For more information, see
Prerequisites
To use multicast routing, the switch must be running the IP services image.
Router A
Source
Receiver
Router C
RP
Router B
Shared tree
from RP
Source tree
(shortest
path tree)
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Содержание IE 4000
Страница 12: ...8 Configuration Overview Default Settings After Initial Switch Configuration ...
Страница 52: ...48 Configuring Interfaces Monitoring and Maintaining the Interfaces ...
Страница 108: ...104 Configuring Switch Clusters Additional References ...
Страница 128: ...124 Performing Switch Administration Additional References ...
Страница 130: ...126 Configuring PTP ...
Страница 140: ...136 Configuring CIP Additional References ...
Страница 146: ...142 Configuring SDM Templates Configuration Examples for Configuring SDM Templates ...
Страница 192: ...188 Configuring Switch Based Authentication Additional References ...
Страница 244: ...240 Configuring IEEE 802 1x Port Based Authentication Additional References ...
Страница 274: ...270 Configuring SGT Exchange Protocol over TCP SXP and Layer 3 Transport Configuring Cisco TrustSec Caching ...
Страница 298: ...294 Configuring VLANs Additional References ...
Страница 336: ...332 Configuring STP Additional References ...
Страница 408: ...404 Configuring DHCP Additional References ...
Страница 450: ...446 Configuring IGMP Snooping and MVR Additional References ...
Страница 490: ...486 Configuring SPAN and RSPAN Additional References ...
Страница 502: ...498 Configuring Layer 2 NAT ...
Страница 559: ...555 Configuring Network Security with ACLs How to Configure Network Security with ACLs Creating a Numbered Extended ACL ...
Страница 770: ...766 Configuring IPv6 MLD Snooping Related Documents ...
Страница 930: ...926 Configuring IP Unicast Routing Related Documents ...
Страница 956: ...952 Configuring IPv6 Unicast Routing Configuring IPv6 network 2010 AB8 2 48 network 2010 AB8 3 48 exit address family ...
Страница 976: ...972 Configuring Cisco IOS IP SLAs Operations Additional References ...
Страница 978: ...974 Dying Gasp ...
Страница 990: ...986 Configuring Enhanced Object Tracking Monitoring Enhanced Object Tracking ...
Страница 994: ...990 Configuring MODBUS TCP Displaying MODBUS TCP Information ...
Страница 996: ...992 Ethernet CFM ...
Страница 1030: ...1026 Working with the Cisco IOS File System Configuration Files and Software Images Working with Software Images ...
Страница 1066: ...1062 Using an SD Card SD Card Alarms ...