chris@sparta.UUCP (Chris Chiotasso) (12/05/89)
I have the CMU public domain code and am porting it. There is an address in the documentation to direct questions to. The address given is: sw01+snmp@andrew.cmu.edu. I have tried this address in many different forms (eg. sw01 as #1 and letter l, snmp only etc) and have had them all returned to me. Does anyone have the correct address and/or an answer to the following question. I read the code and found that the object id's are encoded with the first 2 subids in a single subid field using (x*40)+y x=1st subid and y=2nd subid. I have also read the RFC's and have not found any reference to this. Am I missing something? Why are the first 2 ids combined?
aw0g+@ANDREW.CMU.EDU (Aaron Wohl) (12/05/89)
That address is sw0l+snmp@andrew.cmu.edu
karl@asylum.SF.CA.US (Karl Auerbach) (12/06/89)
In article <237@sparta.UUCP> chris@sparta.UUCP (Chris Chiotasso) writes: >I read the code and found that the object id's are encoded with the >first 2 subids in a single subid field using (x*40)+y x=1st subid >and y=2nd subid. > >I have also read the RFC's and have not found any reference to this. >Am I missing something? Why are the first 2 ids combined? You have stumbled onto a growing problem -- RFC's which require knowledge which is not present in the RFC itself or another RFC. The answer to your question is in an OSI document, named "ISO 8825 Information Processing Systems - Open Systems Interconnection - Specification of Basic Encoding Rules for Abstract Syntax Notation One (ASN.1)" You need to look at section 20. What it says is exactly what you found -- the first two object identifier components are combined into a single subidentifier. Why? I don't know -- probably because they felt they could save a byte. You'll probably find other things in SNMP that require refernce to ISO 8825 and its companion ISO 8824. You can get copies (for $$) from a number of sources. I tend to use Omnicom in Vienna, Virginia. You may also find that some SNMP implementations don't do perfect ASN.1 encoding. (For example, you may see COUNTERS, GAUGES [i.e. unsigned types] being mis-encoded as negative signed integers when high order bit is a 1. Problems haven't occurred because most of us tend to use machines that use 32 bit long integers and two's complement math.) --karl--
ww0n+@ANDREW.CMU.EDU (Walter Lloyd Wimer III) (12/07/89)
The E-mail address for comments about the CMU SNMP package is:
Steve Waldbusser <sw0l+snmp@andrew.cmu.edu>
That userid is "s" (as in "Steve"), "w" (as in "Waldbusser"), zero, ell.
The "+snmp" part is a hint to our mail system to direct such mail to
Steve's special SNMP mail folder.
Obviously, you needn't type Steve's whole name if you don't want to; the
part within angle brackets will suffice.
Walt Wimer
Network Development
Carnegie Mellon Universitylmg@hpindda.HP.COM (Lisa Gullicksen) (12/07/89)
> from / chris@sparta.UUCP (Chris Chiotasso) / 10:59 am Dec 4, 1989 / > > >I read the code and found that the object id's are encoded with the >first 2 subids in a single subid field using (x*40)+y x=1st subid >and y=2nd subid. > >I have also read the RFC's and have not found any reference to this. >Am I missing something? Why are the first 2 ids combined? The encoding of the first 2 subids in a single subid field as (x*40)+y is described in ISO 8825 "Specification of Basic Encoding Rules for Abstract Syntax Notation One (ASN.1)" in section 20.4. Section 20 covers "Encoding of an object identifier value." Lisa Gullicksen e-mail: lmg@hpindda.hp.com
jara@fulcrum.bt.co.uk (Jujhar Kandhola) (05/31/91)
Could somebody out there send me some information on the the
"Simple Network Management Protocol". A high level description
would be great along with details of where I can obtain some further
information.
If this is the not the newsgroup in which I should be asking this question
I apologise.
Cheers
Jarascoggin@delmarva.delmarva.COM (John Scoggin) (06/02/91)
I would suggest reading RFC's 1157, 1158, and 1159. There is an EXCELLENT book on the subject of SNMP - "The Simple Book" by Dr. Marshall T. Rose (Prentice-Hall, 1990). This is a good starting point. -- John ---------------------------------------------------------------------- John K. Scoggin, Jr. Supervisor, Network Operations Phone: (302) 451-5200 Delmarva Power & Light Company Fax: (302) 451-5321 500 N. Wakefield Drive Email: scoggin@delmarva.com Newark, DE 19714-6066 ----------------------------------------------------------------------
kzm@hls.com (Keith McCloghrie) (06/02/91)
> I would suggest reading RFC's 1157, 1158, and 1159. Oops, a typo. Actually, it's 1155 (for the SMI), 1156 (for MIB-I), 1157 (for the protocol, SNMP). 1158 is MIB-II but has been obsoleted by 1213. 1159 is on a different subject. (And if you're a glutton for punishment, I recommend 1212 also). > There is an EXCELLENT > book on the subject of SNMP - "The Simple Book" by Dr. Marshall T. Rose > (Prentice-Hall, 1990). > This is a good starting point. Agreed. Keith.