
426
C
HAPTER
18: IP M
ULTICAST
R
OUTING
How a Network
Supports IP
Multicast
To support IP multicast, the sending and receiving nodes, as well as the
network infrastructure between them, must be multicast-enabled.
Specifically, there must be cohesive support for IP multicast in the
following components: TCP/IP protocol stack, operating systems,
application software, NICs, and Layer 3 devices. Support for IP multicast
in Layer 2 devices is not required by the standard, but is desirable, as
explained later in this section.
IP Multicast Routing
IP multicast transmissions fundamentally depend on multicast-enabled
Layer 3 devices (traditional routers or Layer 3 switches; hereafter both are
called
routers
) to direct packets on an efficient path from sources to
destinations.
As shown in Figure 50, routers that support IP multicast must accomplish
two important tasks:
■
Communicate with other routers to determine the shortest, loopfree
delivery path between an IP multicast source and its group members
■
Communicate with hosts on its directly attached subnetworks to
determine which hosts want to join or leave IP multicast groups
Figure 50
IP Multicast Communication Processes
IP multicast application sources
L3
L3
L3
Router-to-router
communication
Router-to-host
communication
Router-to-host
communication
Содержание 4007
Страница 1: ...http www 3com com Switch 4007 Implementation Guide Release 3 0 5 Part No 10013673 Published May 2000 ...
Страница 36: ...36 ABOUT THIS GUIDE ...
Страница 37: ...I UNDERSTANDING YOUR SWITCH 4007 SYSTEM Chapter 1 Configuration Overview ...
Страница 38: ......
Страница 50: ...50 CHAPTER 1 CONFIGURATION OVERVIEW ...
Страница 52: ......
Страница 70: ...70 CHAPTER 3 INSTALLING MANAGEMENT MODULES ...
Страница 110: ...110 CHAPTER 4 CONFIGURING AND USING EME OPTIONS ...
Страница 130: ...130 CHAPTER 5 MANAGING THE CHASSIS POWER AND TEMPERATURE ...
Страница 222: ...222 CHAPTER 11 IP MULTICAST FILTERING WITH IGMP ...
Страница 240: ...240 CHAPTER 13 RESILIENT LINKS ...
Страница 304: ...304 CHAPTER 14 VIRTUAL LANS VLANS ...
Страница 350: ...350 CHAPTER 15 PACKET FILTERING ...
Страница 506: ...506 CHAPTER 19 OPEN SHORTEST PATH FIRST OSPF ROUTING ...
Страница 534: ...534 CHAPTER 20 IPX ROUTING ...
Страница 612: ...612 CHAPTER 22 QOS AND RSVP ...
Страница 656: ...656 CHAPTER 23 DEVICE MONITORING ...
Страница 657: ...IV REFERENCE Appendix A Technical Support Index ...
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