Use line buttons to select trunk

[wotech]

Hi all,

Question #1
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I am fairly new to SIP/IAX/Asterisk and the like. I've been doing a lot of reading the past couple weeks on VOIP and Asterisk and SIP. I have a small business and currently I have 4 POTS line from my telco. I have a Panasonic digital key system (just a plain little phone system) and my phone has 4 buttons on the top labeled 'Line 1', 'Line 2', 'Line3', 'Line 4'. Whenever I want to use one of those lines, I just push whichever line button I want to use, then proceed dialing.
My question is, can I do this with Asterisk and a SIP phone and extension? Where I would have a Polycom 600 phone or a Grandstream 2000 with the 4 Line buttons at the top, and have each POTS line configured as a trunk in Asterisk. Then I could push the 'Line 3' button so I would be using trunk #3, and dial the number i want.
I'm guessing I could do this with a dialing plan? e.g. Line 1 would be "9|NXXXXXX" Line 2 would be "8|NXXXXXX", etc. However, I don't want to do this, because it's easier to just hit the button for the line I want to use and dial that way (and that's what my employees are used to; I don't think I could get them to remember wut prefix to dial for each line).

Question #2
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Is there a way to identify which trunk line is ringing when someone calls?
I actually own 2 business, one is mine that I started, and the other business I bought a couple years ago (however for the most part we operate as one biz). When I bought the other biz, I acquired their phone number too. So it's nice to see if someone is calling on business 1's line or business 2's line; as it allows me to handle the customers a little better. So is there a way to show on the phone's display which trunk the call is coming in on?

Any help/advice/information would be unbelievably appreciated!! If you need clarification on what I'm trying to do, I would be happy to provide it. Thanks in advance!!

-Ross

[klkunzler]

Question: Why does it matter what line they dial out on? If it is for long-distance charges etc, you could use an outbound route so that if they dial (564-xxx-xxxx) it would use line one, (565-xxx-xxxx) would use line 2, etc. Or are you worried about intercepting a call in progress while tryin to dial-out (which asterisk takes care of for you automatically). If it doesn't really matter what line they dial-out on and you only have 4 line so that if one is busy, they can use the next you can set this up in outbound routing in AMP (AAH) as well.