Subject: RE: [Megaco] Hexa representation for octet string

From: Padmaja Musti <[email-masked]>
Date: Thu, 11 Oct 2001 10:23:55 +0530

Troy,
In the Implementer's Guide Jun 2001 item 6.40, it is 
suggested to follow the uniform format to send the octet
string in the ABNF. New format is to represent octet strings in
hexa.
regards,
Padma

-----Original Message-----
From: Troy Cauble [mailto:[email-masked]]
Sent: Wednesday, October 10, 2001 7:44 PM
To: Padmaja Musti
Cc: [email-masked]
Subject: Re: [Megaco] Hexa representation for octet string

Padmaja Musti wrote:
> 
> Hi,
> As per IG Jun 2001 - octetString need to be represented in Hexa format.
> This effects SDP,MTP address ... IG does not mention that this Hexa
> should be started with 0x. In other cases like Authentication Header
> and Packages (IG 6.80) Hexa is always started with "0x". Can
> we have a uniform definition.
> regards,
> Padma.

octetString is a misnomer.  It is not in hexadecimal format.

   localDescriptor      = LocalToken LBRKT octetString RBRKT

   remoteDescriptor     = RemoteToken LBRKT octetString RBRKT

   ; octetString is used to describe SDP defined in RFC2327.
   ; Caution should be taken if CRLF in RFC2327 is used.
   ; To be safe, use EOL in this ABNF.
   ; Whenever "}" appears in SDP, it is escaped by "\", e.g., "\}"
   octetString          = *(nonEscapeChar)
   nonEscapeChar        = ( "\}" / %x01-7C / %x7E-FF )

-troy

_______________________________________________
Megaco mailing list
[email-masked]
http://www1.ietf.org/mailman/listinfo/megaco

---

From: Troy Cauble <[email-masked]>
Date: Thu, 11 Oct 2001 10:37:03 -0400

Padma,

I think you mean IG 6.44.

It confused me too when I first saw it and I posted a very
incendiary letter to the list :)  I was told that IG 6.44
was for "something else not defined yet".  I think someone
even pointed out that (most of!) 6.44 referenced "octet string"
and of course that isn't the same as "octetString"!

The 6.44 description should really be changed.  It states
EXACTLY what you think (and I once thought), but I've been
assured that that's not what was meant!  (Think of the SDP.
Nobody wants to hex encode that.)

The ABNF definition of octetString takes 8-bit characters.
You don't *need* to hex encode it.

-troy