Hi Piotr,

The bytes are in big-endian order (most significant first).  But there is
more to it than that.  The contents are variable length as well, so direct
assignment to an integer type variable on a given system is most likely not
going to work.  You need to process each byte separately and either shift or
multiply by 256 to get the correct value on any given platform.  And you
need to take into account the leading bit to determine if you have a
positive or negative number.

Regards,

Ed Day
Objective Systems, Inc.
http://www.obj-sys.com


----- Original Message -----
From: "Piotr Stefanski" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Monday, August 23, 2004 6:53 AM
Subject: [ASN1] What is the bytes order in ASN.1 message?


> Hi All!
>
> It was a long time before I decided to write to you
> this e-mail.
> Finally I decided to write to you as I am a little bit
> confused with this "BIG/LITTLE ENDIAN" issues in ASN.1
>
> ASN.1 is the standard for communication between
> heterogeneous systems.
> What means also that it "doesn't care" about diversity
> of machine architectures.
> OK. So let's say sender machine encodes some messages
> in ASN.1 and send it on the wire.
> WHAT IS THE STANDARD FOR BYTES ORDER IN ENCODED ASN.1
> MESSAGE?
> Does this ASN.1 standard assume that for example
> mesage should be encoded in big/little endian format
> before sending
> the message in the wire ?
>
> I am asking about this because I am trying to write
> decoding asn.1 function for lenght of TLV and I don't
> know
> if I should check the format (big/little endian) of
> incoming asn.1 binaries first or I can assume already
> that incoming
> asn.1 mesage is in big/little endian format?
>
> Thanks for any kind of explanation ;)
>
> Best regards,
>
> Piotr
>
>
>
>
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