[Asterisk-Users] Silly question: Why multiple lines on SIP phones?

[Michael Graves]

On Sat, 29 Jan 2005 21:17:56 -0500 (EST), Paul Dugas wrote:

>This is probably going to sound really silly and I must be confused about
>it.  Maybe someone can set me straight.
>
>I've been tinkering for a while with * and a number of different FXO/FXS
>cards, SIP phones, and ATAs trying to get a feel for what works and what
>doesn't.  In the SIP phone group, I have a Cisco 7940G, a Polycom 500, and
>now an SPA-841.  Each of these allow me to configure at least 2 "lines". 
>What I'm wrestling with is what to do with the second lines.  With the
>cisco and the polycom, I have only one line configured and can
>successfully conference and transfer calls.  When I'm on the phone and a
>new call comes in, they display the second call and controls for switching
>between them.  (hmmm... what happens when the third comes along?)  The
>Sipura appears to be unable to do this without configuring a second
>extension.  (anybody got any insight on that?)  My question is basically,
>assuming all I want is the same kind of service I get on a traditional
>analog line with respect to call waiting and 3-way, do I need a multi-line
>phone?
>
>Back to the Sipura... If I configure it to only register the first line,
>it seems it cannot conference or transfer calls.  With my current configs,
>a second incoming call to the extension dumps straight to "busy" voice
>mail.  I guess I could setup my dial plan to roll to the phone's line 2
>but that seems like a mess.  It's not needed with the cisco or polycom so
>it's possible, right?

Some phones don't support multiple lines at all. The Zultys 4x4 and 4x5
phones provide 4 "call appearances" but only one registration. That
means that the phone is one extension, one line. However, a second,
third or fourth call incomming/outgoing uses another call appearance.
This acts sort of like a local hunt group...and has turned out to be
very natural to use. There's less administrative and dialplan overhead
than with my Polycom phones.

I started out with three extensions programmed in my Polycom IP600
phones, but eventually knocked them back to only 1. With each extension
having two call appearancs on the IP600 it's more than a mere mortal
can do to manage all the possible call activity.

Michael

--
Michael Graves                           mgraves at pixelpower.com
Sr. Product Specialist                          www.pixelpower.com
Pixel Power Inc.                                 mgraves at mstvp.com

o713-861-4005
o800-905-6412
c713-201-1262