[asterisk-users] Looking for wisdom - One Asterisk system - Multi-incoming trunks

[Steve Edwards]

On Wed, 29 Jul 2009, Myles Wakeham wrote:

> I have setup an Asterisk system for my home & home office.

[snip]

> The cost of all these lines with analog carriers was getting ridiculous, 
> so I'm moving over to a SIP carrier.  I created one account for a single 
> phone number with a SIP carrier (BroadVoice)

[snip]

I've never used BroadVoice, so I have nothing good or bad to say about 
them. I've used Vitelity.net for several years and am pleased with them.

I have a "nominal monthly fee, pay per minute" account. They get $1.49 a 
month for a DID and $0.0144 per minute. You'd have to use about 2,600 
minutes (about 44 hours) before it would cost as much as a $40 per month 
"analog." They have an "unlimited" inbound for $7.95 a month.

> I started the process today to get our other phone numbers moved over to 
> BroadVoice.

[snip]

Vitelity.net charges $18 per number ported. I've never done this.

> My approach is to have one trunk provided by the SIP provider.  All 
> numbers are allocated to that trunk (BroadVoice let me do that when I 
> setup the number transfer).  Asterisk receives an incoming call on that 
> trunk and determines the calling number that it was requesting (not sure 
> how to get this, but Broadvoice assured me I could).  Anyway after 
> determining what the call was destined for, I then route the call to the 
> appropriate context in the extensions to handle it.

The calls should be delivered with the DID (aka DNIS, DDI, etc). Usually 
you pick this up as the ${EXTEN} in your dialplan and go from there.

[snip]

> Broadvoice, however, won't let me change the outgoing caller ID. 
> Apparently they have to do this on a trunk by trunk basis.  So if I want 
> to have an outgoing call go through line 1 (let's say its ACME Inc), I 
> want it to show 'XXX-XXX-XXXX Acme Inc' for the Caller ID.

[snip]

Being able to specify the caller ID number depends on the carrier. 
Vitelity.net does. Specifying the caller ID name is not going to work. The 
way it works (from 40,000 feet) is that the name is not passed onto the 
"real" telephone system. The carrier for the dialed number looks up the 
number in a database and presents that to the dialed number. If you dial 
another VOIP account (sip:john-smith at example.com) your caller ID name 
should be passed.

> Does this sound right?  Should I have purchased all separate trunks up 
> front and then have the phone number transfer associated with the trunk 
> for it?  Or is this only something that will affect outgoing calls, so 
> its not a big deal?  And what about when the line is busy?  How is that 
> handled?  I was on the phone yesterday when another call came in, and it 
> came in, jumped to a different extension and then eventually went to 
> voice mail as I didn't answer it.  Will my plan to use one trunk for all 
> incoming lines make sense here, or am I likely to get all of this mixed 
> up with calls coming in for one business and being routed to the wrong 
> place?

I'm more comfortable with the word "account" than "trunk." You can have 
multiple DIDs numbers associated with the same account. Some providers 
make you specify (via their web site) where you want the calls to go. Some 
make you configure your Asterisk server so it "registers" with their 
server. I prefer registration because it let's me change things around 
easier.

-- 
Thanks in advance,
-------------------------------------------------------------------------
Steve Edwards       sedwards at sedwards.com      Voice: +1-760-468-3867 PST
Newline                                              Fax: +1-760-731-3000