Table of Contents

IP Multicast

General

cisco_ip_multicast_routing_protocols_43274.jpg

IGMP Snooping

Essentially, IGMP snooping is a layer 2 optimization for the layer 3
IGMP protocol. IGMP snooping takes place internally on switches and
is not a protocol feature.

IP multicast addressing

IP Multicast addresses are Class D subnet (first bits: 1110):

224.0.0.0/4    (224.0.0.0-239.255.255.255)

with reserved:

  224.0.0.0/24  network control traffic (routing protocols like OSPF)
  224.0.0.1     all-hosts = all systems on subnet
  224.0.0.2     all-routers = all multicast routers on a subnet
  224.0.0.5     OSPF All Routers
  224.0.0.6     OSPF Designated Routers
  224.0.0.9     RIP2
  224.0.1.1     NTP


  224.0.1.0/24  Internetwork Control Block (RSVP, DHCP) 

  224.1.0.0/16  ST Multicast Groups

  224.2.0.0/16  SDP/SAP Block

  239.0.0.0/24  reserved for boundaries

IP to MAC mapping

According to IPv4 multicast standards, the MAC destination multicast
address begins with 01:00:5e and is appended by the last 23 bits of
the IP address.
01:00:5e:00:00:00-01:00:5e:7f:ff:ff

224.128.64.32 -> 01:00:5e:00:40:20

MBONE

IGMP

wikipedia_igmp_550px-igmp.jpg

PIM

DVMRP

Novell Imaging over Multicast

http://www.novell.com/documentation/zenworks65/index.html?page=/documentation/zenworks65/dmadmin/data/a7jl098.html

The name of the multicast session. Each workstation joining the
session uses the same value for this parameter.

NOTE:  The name must be unique among concurrent multicast sessions.
It is hashed by the imaging engine to produce a Class D IP address
for the multicast session. To facilitate troubleshooting (wire
sniffing), all Desktop Management Workstation Imaging multicast
addresses start with 231. For example, the session name doug produces
the multicast address 231.139.79.72.

Reliable Multicast

Cisco

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