[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Protocol operations proposal deadline

Hi -

> Date: Fri, 6 Sep 2002 10:22:15 +0200
> Message-Id: <200209060822.g868MFcY017375@hansa.ibr.cs.tu-bs.de>
> From: Juergen Schoenwaelder <schoenw@ibr.cs.tu-bs.de>
> To: abierman@cisco.com
> Cc: eos@ops.ietf.org
> Subject: Re: Protocol operations proposal deadline
> References: <>
> Although we should learn from history and have a few unused bits in
> the new PDU format. The traditional Internet protocol formats always
> lead to some unused bits due to the alignment of various fields. ASN.1
> itself does not lead to some unused bits in this natural way and so
> they have to be designed into the protocol.

This is a limitation of the way the IETF has used ASN.1, rather
than ASN.1 itself.  By using "extensibility markers" or the
"DEFINED BY" constructs in the ASN.1 grammar, extensibility
is readily supported.  Examples include X.500 and that other
management protocol.

But, to the topic of this thread, I agree that "little tweaks"
to the PDU can sometimes increase implementation complexity
disproportionately. For new operation types, in the long run I
think it's simpler to define an operation syntax that suits the
requirements of the operation semantics, rather than forcing
everything onto the existing PDU layout.  This also forces us
to be honest about the fact that we're defining a new protocol.

 Randy Presuhn          BMC Software, Inc.  SJC-1.3141
 randy_presuhn@bmc.com  2141 North First Street
 Tel: +1 408 546-1006   San Jos, California 95131  USA
 My opinions and BMC's are independent variables.