[rohc] rfc5225 msn_lsb improvement

[Klaus Warnke <[e-mail]>]

Hello everybody,

I think, the msn_lsb() encoding method could be improved:

msn_lsb(k)
{
...
   COMPRESSED none {
     ENFORCE(reorder_ratio.UVALUE == REORDERING_NONE);
     master =:= lsb(k, 1);
   }
...
}

For reorder ratio REORDERING_NONE the
     master =:= lsb(k, -1);

is sufficient. That is, offset_param = -1,
If there is no reordering, there is no need to have a lower bound -1 
before the ref_value.
If the msn increase by +1, the lower bound could be ref_value +1.

See also rfc3095:

    a) For field values that are expected always to increase, p can be
       set to -1.  The interpretation interval becomes
       [v_ref + 1, v_ref + 2^k].


Any comments?

Regards,
Klaus

-- 
Klaus Warnke		[e-mail]
http://www.acticom.de
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