PER is a fixed set of encoding rules. You have no control over the
encoding (other than by writing contorted ASN.1). With ECN, however,
you have complete control over the enocoding, and in particular can
specify byte reversal, swapping of byte half-units, or reversal within
half-units before the bits are sent down the line.
ECN is designed to make it possible to write "clean" ASN.1 for any
legacy protocol, with no change to the bits on the line. However, for
this to be useful, you need tool support for ASN.1+ECN. Such support is
still at the alpha/beta test level.
John L
OSIX Mark Svensson wrote:
>
> Do I have the possibility to decide if types are to be read with the least
> or most significant bit first? Can I do it using PER? Can I do it using ECN?
> For example the MTP protocols use least significant bit first whilst IP use
> most significant bit first.
>
> /Mark
> ____________________________________________
> Mark Svensson
> OSIX AB, Lumavägen 6, SE-120 31 Stockholm, Sweden
> Tel +46(0)8 50 600 668, Fax +46(0)8 50 600 601
> Mob +46(0)709 703 201, http://www.osix.se
--
========================================================================
Prof John Larmouth
1 Blueberry Road, Bowdon, Altrincham, Cheshire WA14 3LS, England.
j.larmouth @ salford.ac.uk Tel: +44 161 928 1605
Fax (work): +44 161 745 8169 Tel (work): +44 161 295 5657
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