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9. Rules for dropping or temporarily storing packets

When a decompressor receives a packet with a compressed TCP header with CID C, it MUST be discarded when the context for C has not been initialized by a full header.

When a decompressor receives a packet with a compressed non-TCP header with CID C and generation G, the header must not be decompressed using the current context when

  a) the decompressor has been disconnected from the compressor for
      more than MIN_WRAP seconds, because the context might be
      obsolete even if it has generation G.

  b) the context for C has a generation other than G.

In case a) and b) the packet may either be

  i)  discarded immediately, or else

  ii) stored temporarily until the context is updated by a packet
      with a full non-TCP header with CID C and generation G, after
      which the header can be decompressed.

      Packets stored in this manner MUST be discarded when

        *)  receiving full or compressed non-TCP headers with CID C
            and a generation other than G,

        *)  the decompressor has not received packets with CID C in
            the last MIN_WRAP seconds.

When full headers are lost, a decompressor can receive compressed non-TCP headers with a generation value other than the generation of its context. Rule ii) allows the decompressor to store such headers until they can be decompressed using the correct context.

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