What does it mean to "evaluate" an object identifier, I mean, "resolve" it?

I'm curious to know how the recipient uses an object identifier once he's got
it.

William

--- "Sathya[IT]" <[EMAIL PROTECTED]> wrote:
> Hi Justin,
> 
> Long ago, back in 1986, ASN.1 specification considered a wastage of octets
> to use 2 bytes for the first 2 roots. So they juxtaposed both into a single
> octet using the formula Root * 40 + Second root. This was due to the fact
> that there ar only 3 root nodes (ITU-T, ISO and Joint ISO-ITU). Since the
> values of OID are encoded in 7Bit encoded Integer. We can have only 128
> values for this juxtaposed integer to be represented in a single octet.
> 128/3 is approx. 40.
> The first 40 is given to ITU-T, the next 40 to ISO and the rest to joint
> iso-itu. This also explains why the second level arc cannot have more than
> 40 siblings.
> 
> Hope this will clarify your doubt.
> 
> regards,
> 
> Sathya Narayanan S
> RPG Cellular Services Limited
> GSM : +91 98410 48051
> 
> > -----Original Message-----
> > From:       Hwang, Justin 
> > Sent:       Thursday, November 15, 2001 10:13 PM
> > To: '[EMAIL PROTECTED]'
> > Subject:    RE: [ASN.1] itu-t (0) recommendation (0) h (8) 245 version
> > (0) 2
> > 
> > Hi,
> > 
> > I never decode OBJECT ID before, so please
> > help me with the following questions.
> > 
> > > itu-t (0) recommendation (0) h (8) 245 version (0) 2
> > > 1) 40 * 0 + 0 = 0
> > 
> > ===> Why 40? where 40 comes from? and why only 1 byte for both "itu-t (0)
> > recommendation (0)"? why not 2 bytes? 1 byte (0) for itu-t and other byte
> > (0) for recommendation?
> > 
> > > 2) 8
> > > 3+4) 245 = 11110101B => 1 0000001 0 1110101 = F1 75
> > 
> > ===> How "11110101B" is converted to "1 0000001 0 1110101"?
> > 
> > > 5) 0
> > > 6) 2
> > 
> > 
> > Thanks!
> > 
> > Justin
> > 
> > 
> > -----Original Message-----
> > From: Sathya[IT] [mailto:[EMAIL PROTECTED]]
> > Sent: Thursday, November 15, 2001 3:35 AM
> > To: [EMAIL PROTECTED]
> > Subject: RE: [ASN.1] itu-t (0) recommendation (0) h (8) 245 version (0)
> > 2
> > 
> > 
> > Hi Bernd,
> > 
> > While I encode this, the octets turn out to be 00 08 81 75 00 02
> > 
> > I dont understand how you arrived at f1 instead of 81. Is there a
> > significance 
> > for the deviation?
> > 
> > regards,
> > 
> > Sathya Narayanan S
> > RPG Cellular Services Limited
> > GSM : +91 98410 48051
> > 
> > > -----Original Message-----
> > > From:     Bernd Kunze 
> > > Sent:     Monday, November 05, 2001 9:15 PM
> > > To:       '[EMAIL PROTECTED]'
> > > Subject:  RE: [ASN.1] itu-t (0) recommendation (0) h (8) 245 version
> > > (0) 2
> > > 
> > > Hi,
> > > 
> > > itu-t (0) recommendation (0) h (8) 245 version (0) 2
> > > 
> > > 1) 40 * 0 + 0 = 0
> > > 2) 8
> > > 3+4) 245 = 11110101B => 1 0000001 0 1110101 = F1 75
> > > 5) 0
> > > 6) 2
> > > 
> > > => 00 08 F1 75 00 02
> > > 
> > > Bernd


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