Path: utzoo!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!mit-eddie!minya!jc
From: jc@minya.UUCP (John Chambers)
Newsgroups: comp.protocols.iso
Subject: Just what are the ASN.1 type codes?
Keywords: ASN.1, PER
Message-ID: <544@minya.UUCP>
Date: 6 Mar 91 04:49:43 GMT
Distribution: comp.protocols.iso
Lines: 33

For some time now, I've been trying to get together in one .h file a
definitive list of the ASN.1 type codes.  This isn't easy.  I found
some of them in an OSI doc. (8825?  It's at work and I'm not, so I'm
probably not remembering the number right.)  Others appear in various
programs' .h files around where I'm working.  I'm generally not too
sure that everything I see is even correct.  For instance, I've seen
several .h files define an IP Address type:
	#define IPID              0x40
which I suspect is not really an ISO standard; then again maybe it 
is, but I've yet to find this code in any ISO document.

Has ISO published the obvious table anywhere?  Have I been staring
at it all along and not recognizing it?  Can someone tell me where
to RTFM to find it?  Or is it all just folklore?

Particularly interesting would be some sort of coherent explanation
of how ISO (OSI?) addressing is really supposed to work; especially
how one might recognize (i.e., parse) one in a message, and what is 
legal to generate in a message.

Note that I'm not particularly interested in the symbolic meta-language
used in most ISO documents.  I need to generate and parse actual packets
as they appear on the network.  So far, the meta-language has been not
very useful in tackling this job.  A table of hex codes would be much
more valuable...

[BTW, is there an ISO FAQ file somewhere?  I've yet to see one.]

-- 
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