[Asterisk-Users] Polycom-Asterisk hints/presence

[Damon Estep]

> 
>  You're right in that there is nothing in technology spec to support
> the concept of shared line appearance, but I think what was more to my
> point was that you could get access to a "shared line" from more
> channels than just a SIP channel. I'd probably want the ability to
> have two SIP channels and an IAX channel in a "shared line group", and
> while SIP provides for structured communication to ask for a
> grant/deny access to this resource, there isn't any reason the same
> couldn't be done off the IAX channel via feaure mapped DTMF just as
> you can "park" a call off of a Zap channel today even though the
> underlying technology has no idea what the concept of Park really is.
> The concept of channels in Asterisk are not technology specific, and
> as a result, implementations of things like "shared lines" really
> shouldn't be either.
> 
> --
> Bird's The Word Technologies, Inc.
> http://www.btwtech.com/


What you are describing is an ability to dynamically "bundle" channels
in the dialplan, that is you would define the members of the group, and
then ring the group instead of the channel, this can already be done
manually.

That is not what the sip version of shared lines does, it allows
simultaneous registrations of multiple user agents into a user agent
account, and then allows any one of the registered UAs to seize the call
when it rings. When the SIP server evaluates where the INVITE should go
it sends it to multiple UAs, and that is the thing asterisk can not do
without a dialplan that tells it to do so and a unique account for each
UA to register on. It is limited to one registration per user account.

I understand your "technology agnostic position", and it makes sense,
however my vote (for the little that it is worth) would be to implement
a SIP rfc complaint shared line appearance capability (and/or bridged
line appearance), and then, if possible, extend it to support zaptel and
iax and whatever else is popular. SIP is arguably the most common choice
for NEW VoIP implementation, and it also appears to be the common ground
upon which all vendors of VoIP gear will meet for interoperability. IAX,
even with its advantages, will not likely progress to the same stage of
universal acceptance, it may very well be the choice of many asterisk
users, but in the end you will still have to talk SIP interoperate with
the "VoIP Revolution"

I can not imagine Nortel, Cisco, Lucent, Sonus, BroadSoft, and
(probably) Polycom, or any of the other commercial players, embracing a
protocol developed and supported by proponents of open source software
:)

If your comments echo those of past conversations on the matter I can
see that a bounty at this point would not be money well spent, since any
work the comes from it is not likely to make the cut. A bounty would
only be useful to accelerate the implementation of a feature where there
is widespread agreement on what the architecture should be.

Damon