Subject: Signals

From: John Segers <[email-masked]>
Date: Thu, 28 Oct 1999 19:39:50 +0200

People,

Based on the discussion, I have drafted the following text.  After
sending it to Brian R., I realized I'd forgotten to include StreamID as
an optional parameters, but that doesn't change the idea.

I left the text for "brief" unchanged; I'm willing to make brief
uninterruptable.

Comments?

John
--
John Segers                                  email: [email-masked]
Lucent Technologies                                        Room HE 306
Dept. Forward Looking Work                      phone: +31 35 687 4724
P.O. Box 18, 1270 AA  Huizen                      fax: +31 35 687 5954

Subject: Signals
From: John Segers <[email-masked]>
To: Brian Rosen <[email-masked]>
Date: Thu, 28 Oct 1999 19:18:08 +0200

Brian, Tom,

Here's some draft text for the signals descriptor section.  It does
basically what you proposed, but is slightly more general.  Let me know
what you think.

John

A SignalsDescriptor is a parameter that contains the set of signals that
the Media Gateway is asked to apply to a Termination. A
SignalsDescriptor contains a number of signals and/or sequential signal
lists.  A SignalsDescriptor may contain zero signals and sequential
signal lists.  Support of sequential play lists is optional.

Signals are defined in packages.  Signals shall be named with a Package
name (in which the signal is defined) and a SignalID.  Signals may have
parameters.  This allows a single signal to have some variation in
meaning, obviating the need to create large numbers of individual
signals.

There are three types of signals:
· on/off - the signal lasts until it is turned off,
· timeout - the signal lasts until it is turned off or a specific period
of time elapses,
· brief - the signal duration is so short that it will stop on its own
unless a new signal is applied that causes it to stop; no timeout value
is needed.

A sequential signal list consists of an identifier, a sequence of
signals to be played sequentially, and a signal type.  Only the trailing
element of the sequence of signals in a sequential signal list may be an
on/off signal.  If the trailing element fo the sequence is an on/off
signal, the signal type of the sequential signal list shall be on/off as
well.  A signal list is treated as a single signal of the specified type
when played out.

Multiple signals and sequential signal lists in the same
SignalsDescriptor shall be played simultaneously.

Signals are defined as proceeding from the termination towards the
exterior of the Context.  When the same Signal is applied to multiple
Terminations within one Transaction, the MG should consider using the
same resource to generate these Signals.
 
Production of a Signal on a Termination is stopped by application of a
new SignalsDescriptor, or detection of an Event on the Termination (see
Section 7.1.9).
 
A new SignalsDescriptor replaces any existing SignalsDescriptor.  Any
signals applied to the Termination not in the replacement descriptor
shall be stopped, and new signals are applied.  Signals present in both
the existing and replacement descriptor, with the same parameters in
both, shall be continued.  If the replacement descriptor contains a
sequential signal list with the same identifier as the existing
descriptor, then
· the sequence of signals in the sequential signal list in the
replacement descriptor shall be empty, and
· the playing of the signals in the sequential signal list in the
existing descriptor shall not be interrupted.

-- 
John Segers                                  email: [email-masked]
Lucent Technologies                                        Room HE 306
Dept. Forward Looking Work                      phone: +31 35 687 4724
P.O. Box 18, 1270 AA  Huizen                      fax: +31 35 687 5954