IP multicasting
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... IP) to support multicasting. It is
proposed as a standard for IP multicasting in the Internet. This
specification is a major revision of RFC-988(-> 1112std5 | 1054(-> 1112std5)) ...
... There are three levels of conformance to this specification:
Level 0: no support for IP multicasting.
There is, at this time, no requirement ...
... requirement that all IP implementations
support IP multicasting. Level 0 hosts will, in general, be
unaffected by multicast ...
... destination address field; they should be quietly
discarded by hosts that do not support IP multicasting. Class D
addresses ...
... implementations.
Level 2: full support for IP multicasting.
Level 2 allows a host ...
... multicast IP datagrams. To support level
2 IP multicasting, a host must also support the reception of
multicast ...
... IP. It is required to be
implemented by all hosts conforming to level 2 of the IP multicasting
specification. IGMP messages are encapsulated ...
...
This appendix is not part of the IP multicasting specification, but
provides background discussion of several issues related to IP ...