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

2000-06-22 23:46:37
Right,

OID string representation is not part of the ASN.1 languange specification.
ASN.1 is used for specification of protocols, mostly in OSI, and ITU-T
standards. 
I think you should take a look at the RFCs dealing with string
representation syntaxes. 
In particular RFCs related to X.500 and LDAP technology.

Panagiotis Tsigaridas

IT Architecture Manager




-----Original Message-----
From: Christian Huitema [mailto:huitema(_at_)microsoft(_dot_)com]
Sent: Friday, June 23, 2000 4:07 AM
To: 'Peter Furniss'; 'ietf(_at_)ietf(_dot_)org'; 'Michael Mealling'
Subject: RE: Where is the OID "dot convention" spelled out?


The notation of OID strings as 1.3.6.1.4.1 started appearing in the ISODE
ASN.1 compiler, in the late 80's. It was not part of the ASN.1 standard; in
fact, ASN.1 defines its own set of format, that can mix numbers and
litterals. In ASN.1, this was called a "value notation." A standard ASN.1
textual representation would have been, for example, {1 3 6 1 4 1}, or {1 3
6 foo(1) bar(4) 1}, as in
        fooBar OBJECT IDENTIFIER ::= {1 3 6 foo(1) bar(4) 1}
Why the ASN.1 representation never really caught up in user interfaces is
left as an exercize for the reader...

-----Original Message-----
From: Peter Furniss 
[mailto:p(_dot_)furniss(_at_)mailbox(_dot_)ulcc(_dot_)ac(_dot_)uk]
Sent: Thursday, June 22, 2000 4:13 PM
To: 'ietf(_at_)ietf(_dot_)org'; 'Michael Mealling'
Subject: RE: Where is the OID "dot convention" spelled out?


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