integrity transform
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... ROC is carried in
the authentication tag of a special integrity transform in selected
SRTP packets.
...
... The benefit of this approach is that the functionality of fast and
robust synchronization can be achieved as a separate integrity
transform, using the hooks existing in SRTP. Furthermore, when the
ROC ...
... sender computes the MAC in the same way as is done
when using the default integrity transform (i.e., HMAC-SHA1(auth_key,
...
... TAG and verifies the MAC computed (in the same
way as if the default integrity transform was used) over the
authenticated portion of the packet (as defined in [RFC3711 ...
... the packets that do not have SEQ equal to 0 mod R MUST be protected
using the default integrity transform (this will be referred to as
mode 2).
...
... RCC requires that a few parameters are signaled out of band. The
parameters that must be in place before the transform can be used are
integrity transform mode and the rate, R, at which the ROC will be
transmitted. This can be done using, e.g., MIKEY ...
... RFC3830].
Table 2. Integrity transform parameter
Type | Meaning | Possible values
...
... using RCCm1 or RCCm2, as with the default integrity transform in RFC
3711prop, the tag-length ...