> -----Original Message-----
> From: Barry Desborough [mailto:[EMAIL PROTECTED]]
> Sent: Tuesday, May 22, 2001 9:20 AM
> To: [EMAIL PROTECTED] (E-mail)
> Subject: FW: [Sip-implementors] plug/unplug SIP phone ??
>
>
> Yes. The REGISTER method is meant to indicate the presence of
> users, not
> phones, but if there are no current registrations associated
> with a SIP
> phone, there's nobody to call even if the phone _is_ on the net.
>
> Barry Desborough
REGISTER conveys address bindings. This means it indicates that a user is
now available at a specific location, which may or may not be a device (I
can register that I, sip:[EMAIL PROTECTED], am now available at
sip:[EMAIL PROTECTED], for example. In this case,
[EMAIL PROTECTED] is not a device, but another identity for myself).
So, the existence of a registration for some user can be used by a SIP
provider to determine that the user is reachable, through a device or some
other means.
-Jonathan R.
---
Jonathan D. Rosenberg, Ph.D. 72 Eagle Rock Ave.
Chief Scientist First Floor
dynamicsoft East Hanover, NJ 07936
[EMAIL PROTECTED] FAX: (973) 952-5050
http://www.jdrosen.net PHONE: (973) 952-5000
http://www.dynamicsoft.com
>
> -----Original Message-----
> From: Bob Penfield [mailto:[EMAIL PROTECTED]]
> Sent: 22 May 2001 14:08
> To: Barry Desborough; [EMAIL PROTECTED]
> Cc: [EMAIL PROTECTED]
> Subject: Re: [Sip-implementors] plug/unplug SIP phone ??
>
>
> Actually, the REGISTER message can be viewed as a SIP phone's
> "here I am,
> I'm up" depending on the expiration time in the registration.
> If the SIP
> phones re-registration interval is relatively short (on the
> order of a few
> minutes) the outbound proxy knows that it is there. If the
> proxy does not
> receive another REGISTER when the registration expires, it
> could consider
> the phone down and stop sending it INVITEs.
>
> (-:bob
>
> Robert F. Penfield
> Chief Software Architect
> Acme Packet, Inc.
> 130 New Boston Street
> Woburn, MA 01801
> [EMAIL PROTECTED]
>
> ----- Original Message -----
> From: "Barry Desborough" <[EMAIL PROTECTED]>
> To: <[EMAIL PROTECTED]>
> Cc: <[EMAIL PROTECTED]>
> Sent: Tuesday, May 22, 2001 8:10 AM
> Subject: RE: [Sip-implementors] plug/unplug SIP phone ??
>
>
> > The absence of any current registrations, and the absence of INVITE
> > responses - that's all there is within the scope of SIP as
> far as I know.
> > There are no <<here I am, I'm up>> messages specified for the phone
> itself.
> >
> > Maybe I don't understand your question, but you _have_ to
> try sending
> > messages to see if a SIP phone is on the net. Hopefully,
> all SIP phones
> > support PING. Some may support SNMP.
> >
> > Barry Desborough
> >
> > -----Original Message-----
> > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]
> > Sent: 22 May 2001 12:47
> > To: Barry Desborough
> > Cc: [EMAIL PROTECTED]
> > Subject: RE: [Sip-implementors] plug/unplug SIP phone ??
> >
> >
> > Quoting Barry Desborough <[EMAIL PROTECTED]>:
> >
> > > If you're concerned about a SIP phone being unplugged
> with a call up,
> > > you
> > > can send periodic INVITEs for the current call leg and check for
> > > responses.
> > > Also, you could also check for ICMP destination/port unreachable
> > > messages
> > > for signaling and media.
> > >
> > > Barry Desborough
> >
> > OK, but we are not notified that a SIP phone is unplugged
> when no call is
> > up.
> > To Check ICMP messages I have to send messages. What if no
> messages are
> sent
> > ?
> > Does it mean that there no offcial mechanism to check
> plug/unplug state of
> a
> > SIP
> > phone?
> >
> > patrick
> > _______________________________________________
> > Sip-implementors mailing list
> > [EMAIL PROTECTED]
> > http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
> >
> _______________________________________________
> Sip-implementors mailing list
> [EMAIL PROTECTED]
> http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
>
_______________________________________________
Sip-implementors mailing list
[EMAIL PROTECTED]
http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
