2, 1, and 0, regardless of the current mode of operation [2].
CCE() may be used when the checksum coverage deviates from the change
pattern assumed by the compressor, where the field could previously
be compressed. This packet is useful if the occurrence of such
deviations is rare.
5.3.2.2. Properties of CCE(ON)
In addition to the updating properties of the inner packet type,
CCE(ON) updates context(CFP) to a nonzero value; i.e., it effectively
turns on the presence of the Checksum Coverage field within the
general packet format. This is useful when the predominant change
pattern of the checksum coverage precludes its compression.
CCE(ON) can extend any of the context-updating packets of type 2, 1,
and 0; that is, packets with a compressed header containing a CRC
[2]. Specifically, R-0 and R-1* headers MUST NOT be extended by
using CCE(ON).
5.3.2.3. Properties of CCE(OFF)
In addition to the updating properties of the inner packet type,
CCE(OFF) updates context(CFP) to a value of zero; i.e., it
effectively turns off the presence of the Checksum Coverage field
within the general packet format. This is useful when the change
pattern of the checksum coverage seldom deviates from the pattern
assumed by the compressor.
CCE(OFF) also updates context(CFI) to a nonzero value, if field(UDP-
Lite Checksum Coverage) is equal to the packet length; otherwise, it
must be set to zero. Note that when context(CFI) is updated by using
packet type CCE(OFF), a match of field(Checksum Coverage) with the
packet length always has precedence over a match with
context(Checksum Coverage). Finally, context(UDP-Lite Checksum
Coverage) is also updated by CCE(OFF).
Similarly to CCE(ON), CCE(OFF) can extend any of the context updating
packets of type 2, 1, and 0 [2].
5.4. Compressor Logic
If hdr(UDP-Lite Checksum Coverage) is different from context(UDP-Lite
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