The formal phrases are "encode into a bit-field" and "encode into an
octet-aligned bit-field", not "insertion of padding bits".  For
*unaligned* PER, *both* of the former are transmitted with no padding
bits.

So for unaligned PER any ambiguity over whether the encoding produces a
"bit-string" or an "octet-aligned bit-string" (and I have not checked
whether the text is ambiguous - I suspect it is NOT) is irrlevant.  The
end result is the same - no padding bits.

John L

> Ed Day wrote:
> 
> Hi,
> 
> There seems to be some question among some groups that we have dealt
> with whether PER unaligned is always unaligned.  It would seem to me
> that clause 7.7 is quite clear on this point that padding bits are
> never inserted, but others we have dealt with claim the note in clause
> 16 on OCTET STRING's indicates padding bits should be inserted because
> it does not discern between aligned and unaligned forms.  It simply
> states that "Octet strings of fixed length less than or equal to two
> octets are not octet aligned.  All other octet strings are aligned.
> etc..".
> 
> Can someone please definitively state that padding bits are never
> inserted, even in this case?
> 
> Thanks,
> 
> Ed Day
> Principal Engineer
> Objective Systems, Inc.
> [EMAIL PROTECTED]
> (484) 875-3020 (main)
> (610) 608-4930 (mobile)
> (610) 321-0361 (fax)
> (877) 307-6855 (toll-free)
> 
> 
> 

-- 
   Prof John Larmouth
   Larmouth T&PDS Ltd
   (Training and Protocol Development Services)
   1 Blueberry Road                     
   Bowdon                               [EMAIL PROTECTED]
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