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RE: Where is the OID "dot convention" spelled out?

2000-06-22 16:30:03
Michael Mealling sent :

For all the ASN.1 folks out there:

I'm in the midst of writing up the OID URN namespace document 
(see http://www.ietf.org/internet-drafts/draft-mealling-oid-urn-00.txt)
and it has come to my attention that none of the ASN.1 standards 
define the dot-notation that we use in all sorts of RFCs. I'm specifically
referring to the practice of inserting dots in between each arc as in:
1.3.6.1.4.1

Is anyone aware if this is actually spelled out somewhere? I don't
have the newest ASN.1 docs in front of me so if the're in there
a page reference would be great.

It is an IETF convention, not one defined in the ASN.1 standards. It is used at 
least as early as RFC 1157 (snmp), which refers to "the familiar dot notation" 
- familiar, I'd assumed, in the dot notation of IP addresses. (which seems to 
be first mentioned in RFC 790, though it says it was already in use then (and 
had leading zeros)
 
The ASN.1 standards use spaces between the fields and {braces} round the whole 
lot in text representations. They also use name(number) to identify what the 
fields are, and the first part of a text representation can also be an assigned 
asn.1 value (so a whole subtree can be specified without repeating the value of 
the root all over the place)


Peter Furniss
ISO/IEC JTC1 OSI Maintenance Rapporteur (on behalf of BSI)
OSI Maintenance website: http://www.furniss.co.uk/maint