SSM
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... general requirements that must be followed by systems that implement
the SSM service model; this document defines the concrete application
of those requirements ...
... portions of IGMPv3 and MLDv2 for use with SSM, and presents a number
of clarifications to their behavior when used with SSM addresses ...
... MLDv2 for use with SSM, and presents a number
of clarifications to their behavior when used with SSM addresses.
This document updates the IGMPv3 ...
... requirements of an SSM-aware host. It is important to note that SSM
can be used by any host that supports source filtering ...
... modifications described in this section make SSM work better on an
SSM-aware host, but they are not strict prerequisites for the use of
SSM ...
... SSM-aware host, but they are not strict prerequisites for the use of
SSM.
The 232/8 IPv4 address ...
... semantics
[RFC3306], although today SSM allocations are restricted to
FF3x::/96. ([SSM] has a more thorough discussion ...
... discussion of this topic.) A
host that knows the SSM address range and is capable of applying SSM
...
... host that knows the SSM address range and is capable of applying SSM
semantics to it is described as an "SSM ...
... host or router SHOULD have a configuration option to set
the SSM address range(s). If this configuration option exists, it
MUST default to the IANA ...
... address range(s). If this configuration option exists, it
MUST default to the IANA-allocated SSM range. The mechanism for
setting this configuration option MUST at least allow for manual
configuration ...
... If the host IP module of an SSM-aware host receives a non-source-
specific request to receive multicast traffic ...
... host receives a non-source-
specific request to receive multicast traffic sent to an SSM
destination address, it SHOULD return an error to the application, as
...
... destination address, it SHOULD return an error to the application, as
specified in [MSFAPI] (MODIFICATION). On a non-SSM-aware host, an
application that uses the wrong API ...
... MLDv2) to request delivery
of packets sent to an SSM address will not receive the requested
service ...
... address will not receive the requested
service, because an SSM-aware router (following the rules of this
document) will refuse to process the request, and the application
...
... This section defines the behavior of the SFGMP protocol module on an
SSM-aware host, including two modifications to the protocols as
described in [IGMPv3 ...
... MLDv2]. It also includes a number of
clarifications of protocol operations. In doing so, it documents the
behavior of an SSM-aware host with respect to sending and receiving
...
... router(s) cannot
provide the SFGMP support needed for SSM, and an error is logged when
the host enters compatibility ...
... the host enters compatibility mode for an SSM address, as described
below. In this situation, it is likely that traffic ...
... IGMPv3 or MLDv2 Membership Record. An
SSM-aware host, however, MUST NOT allow its report to be suppressed
in this situation (MODIFICATION). Suppressing reports in this
...
... in this situation (MODIFICATION). Suppressing reports in this
scenario would provide an avenue for an attacker to deny SSM service
to other hosts ...
...
A host implementation may report more than one SSM channel in a
single report either by including multiple sources within a group ...
... State-Change Record
A report may include both SSM destination addresses and non-source-
specific, i.e., Any-Source Multicast ...
... Additionally, a CHANGE_TO_INCLUDE_MODE record may be sent by a host
in some cases, for instance, when the SSM address range is changed
through configuration. A router ...
... IGMPv3,MLDv2], imposing a restriction on
its use for SSM destination addresses. The rationale is that EXCLUDE
mode does not apply to SSM ...
... SSM destination addresses. The rationale is that EXCLUDE
mode does not apply to SSM addresses, and an SSM-aware router ...
... mode does not apply to SSM addresses, and an SSM-aware router will
ignore MODE_IS_EXCLUDE and CHANGE_TO_EXCLUDE_MODE requests in the SSM ...
... SSM-aware router will
ignore MODE_IS_EXCLUDE and CHANGE_TO_EXCLUDE_MODE requests in the SSM
range, as described below.
...
... IGMPv2,
or MLDv1 to report interest in all SSM destination addresses,
unqualified by a source address ...
... destination addresses,
unqualified by a source address. As a result, SSM semantics will no
longer be applied to the multicast group address ...
... MLDv1 query for an address in the SSM range; thus, this
situation only occurs either if the router ...
... range; thus, this
situation only occurs either if the router is not SSM-aware, or if
the host and the router ...
... the host and the router disagree about the SSM address range (for
instance, if they have inconsistent manual configurations).
...
... IGMPv2
Leave and MLDv1 Done messages should not be sent for an SSM address,
unless the sending host ...
... router is not
compliant with this document or that it is not configured with the
same SSM address range(s) as the receiving host ...
... Group-Specific Query for an
SSM address, it must respond with a report if the group matches the
...
... group, again as required by [IGMPv3,MLDv2]. The use of an SSM
address does not modify the behavior of the SFGMPs in this regard.
...
... SSM address range and
is capable of applying SSM semantics to it as described in this
section is described as an "SSM ...
... SSM semantics to it as described in this
section is described as an "SSM-aware" router. An SSM-aware router ...
... section is described as an "SSM-aware" router. An SSM-aware router
MAY have a configuration option to apply SSM ...
... SFGMP Reports are used to report source-specific subscriptions in the
SSM address range. A router SHOULD ignore a group ...
... router SHOULD ignore a group record of either
of the following types if it refers to an SSM destination address:
...
... MLDv2] to prevent non-source-specific
semantics from being applied to SSM addresses, and to avoid reverting
to older-version ...
... address in the source-specific
range could be sent by a non-SSM-aware host. A router SHOULD ignore
...
... It is important that a router not accept non-source-specific
reception requests for an SSM destination address. The rules of
[IGMPv3 ...
... destination address, thus creating a potential for
an attacker to deny SSM service to other hosts on the same link ...