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Hope someone can answer these:

1. Are there any VoIP, packet voice related forums that I could
subscribe to? I am a newbie at VoIP, though I have some
telecom experience.

2. I have a question on the implementation of protocol message
parsing for a protocol like, say, Q.931:
How are Q.931 messages from the network parsed? Some sort of
state machine, obviously, but how does one specify the
mandatory IEs, the message format etc as part of the parser?

Are there any books/online resources that deal with such
protocol design and implementation issues?

3. I have some experience in telecom, and would like to know more
about VoIP. Which book can I refer to? I am not looking for a
"VoIP for Dummies" kind of a book. I know a great deal of telecom
fundamentals, including a fair bit of Q.931. I want to learn
about VoIP architecture, implementation, technologies and
engineering issues.

Also, if there are downloadable resources on this subject on the
Internet, please point me to them.

Thx,
Sicher

"wonna" <> wrote in message
news: om...
> Hope someone can answer these:
>
> 1. Are there any VoIP, packet voice related forums that I could
> subscribe to? I am a newbie at VoIP, though I have some
> telecom experience.

Try news:comp.dcom.voice-over-ip, but it's not very active.

> 2. I have a question on the implementation of protocol message
> parsing for a protocol like, say, Q.931:
> How are Q.931 messages from the network parsed? Some sort of
> state machine, obviously, but how does one specify the
> mandatory IEs, the message format etc as part of the parser?

ASN.1 was invented to solve precisely this problem, but Q.931 was written
before ASN.1 existed and there is no precise definition of the parsing of
Q.931 that I am aware of. You have to read through Q.931 very carefully and
craft code that implements the (sometimes ambiguous) requirements. Or else
buy a commercial stack.

> Are there any books/online resources that deal with such
> protocol design and implementation issues?
>
> 3. I have some experience in telecom, and would like to know more
> about VoIP. Which book can I refer to? I am not looking for a
> "VoIP for Dummies" kind of a book. I know a great deal of telecom
> fundamentals, including a fair bit of Q.931. I want to learn
> about VoIP architecture, implementation, technologies and
> engineering issues.
>
> Also, if there are downloadable resources on this subject on the
> Internet, please point me to them.

Try www.voip-info.org

--
Phil McKerracher
www.mckerracher.org

(wonna) wrote in message news:<. com>...
> Hope someone can answer these:
>
>
> 2. I have a question on the implementation of protocol message
> parsing for a protocol like, say, Q.931:
> How are Q.931 messages from the network parsed? Some sort of
> state machine, obviously, but how does one specify the
> mandatory IEs, the message format etc as part of the parser?
>
> Are there any books/online resources that deal with such
> protocol design and implementation issues?

The Encoding Control Notation (ECN) associated with ASN.1 allows to
formally specify legacy encodings. When an ECN specification is given
to an ECN compiler, the tools output encoding/decoding functions that
are capable of parsing messages.

More information about ECN at:
http://asn1.elibel.tm.fr/ecn/

OSS Nokalva (http://www.oss.com) might give you more information about
an ECN specification for Q.931.

Olivier Dubuisson