C
HAPTER
18
| Multicast Filtering
Layer 2 IGMP (Snooping and Query)
– 452 –
C
OMMAND
U
SAGE
Multicast Router Discovery
There have been many mechanisms used in the past to identify multicast
routers. This has lead to interoperability issues between multicast routers
and snooping switches from different vendors. In response to this problem,
the Multicast Router Discovery (MRD) protocol has been developed for use
by IGMP snooping and multicast routing devices. MRD is used to discover
which interfaces are attached to multicast routers, allowing IGMP-enabled
devices to determine where to send multicast source and group
membership messages. (MRD is specified in draft-ietf-magma-mrdisc-07.)
Multicast source data and group membership reports must be received by
all multicast routers on a segment. Using the group membership protocol
query messages to discover multicast routers is insufficient due to query
suppression. MRD therefore provides a standardized way to identify
multicast routers without relying on any particular multicast routing
protocol.
N
OTE
:
The default values recommended in the MRD draft are implemented
in the switch.
Multicast Router Discovery uses the following three message types to
discover multicast routers:
◆
Multicast Router Advertisement – Advertisements are sent by routers to
advertise that IP multicast forwarding is enabled. These messages are
sent unsolicited periodically on all router interfaces on which multicast
forwarding is enabled. They are sent upon the occurrence of these
events:
■
Upon the expiration of a periodic (randomized) timer.
■
As a part of a router's start up procedure.
■
During the restart of a multicast forwarding interface.
■
On receipt of a Solicitation message.
◆
Multicast Router Solicitation – Devices send Solicitation messages in
order to solicit Advertisement messages from multicast routers. These
messages are used to discover multicast routers on a directly attached
link. Solicitation messages are also sent whenever a multicast
forwarding interface is initialized or re-initialized. Upon receiving a
solicitation on an interface with IP multicast forwarding and MRD
enabled, a router will respond with an Advertisement.
◆
Multicast Router Termination – These messages are sent when a router
stops IP multicast routing functions on an interface. Termination
messages are sent by multicast routers when:
■
Multicast forwarding is disabled on an interface.
■
An interface is administratively disabled.
■
The router is gracefully shut down.
Содержание ES3510MA
Страница 1: ...Management Guide www edge core com 8 Port Layer 2 Fast Ethernet Switch...
Страница 4: ...ABOUT THIS GUIDE 4...
Страница 30: ...CONTENTS 30...
Страница 40: ...FIGURES 40...
Страница 46: ...TABLES 46...
Страница 48: ...SECTION I Getting Started 48...
Страница 72: ...SECTION II Web Configuration 72...
Страница 88: ...CHAPTER 3 Using the Web Interface Navigating the Web Browser Interface 88...
Страница 115: ...CHAPTER 4 Basic Management Tasks Resetting the System 115 Figure 23 Restarting the Switch Regularly...
Страница 116: ...CHAPTER 4 Basic Management Tasks Resetting the System 116...
Страница 154: ...CHAPTER 5 Interface Configuration VLAN Trunking 154...
Страница 216: ...CHAPTER 8 Spanning Tree Algorithm Configuring Interface Settings for MSTP 216...
Страница 350: ...CHAPTER 14 Security Measures DHCP Snooping 350...
Страница 440: ...CHAPTER 17 IP Services Displaying the DNS Cache 440...
Страница 484: ...CHAPTER 19 Using the Command Line Interface CLI Command Groups 484...
Страница 554: ...CHAPTER 21 System Management Commands Switch Clustering 554...
Страница 574: ...CHAPTER 22 SNMP Commands 574...
Страница 582: ...CHAPTER 23 Remote Monitoring Commands 582...
Страница 636: ...CHAPTER 24 Authentication Commands Management IP Filter 636...
Страница 736: ...CHAPTER 29 Port Mirroring Commands RSPAN Mirroring Commands 736...
Страница 816: ...CHAPTER 34 VLAN Commands Configuring Voice VLANs 816...
Страница 830: ...CHAPTER 35 Class of Service Commands Priority Commands Layer 3 and 4 830...
Страница 848: ...CHAPTER 36 Quality of Service Commands 848...
Страница 900: ...CHAPTER 38 LLDP Commands 900...
Страница 910: ...CHAPTER 39 Domain Name Service Commands 910...
Страница 916: ...CHAPTER 40 DHCP Commands DHCP Client 916...
Страница 948: ...CHAPTER 41 IP Interface Commands IPv6 Interface 948...
Страница 950: ...SECTION IV Appendices 950...
Страница 982: ...INDEX 982...
Страница 983: ......
Страница 984: ...ES3510MA E032010 ST R01 149100000046A...