Some beginner questions

Hey all, I have just entered the world of Asterisk, and as my background is in Software Development and not Telephony, I will admit to being a bit confused. I have ventured down this path partially due to some ideas I’ve had and partially becuase I’m always playing with new toys.

I’m hoping you all could help with some basic questions:

  1. First an easy one… Is there any advantage of digital over analog connections to the phone network. I realize there are financial advantages, but from a techincal side, does digital systems like T1 offer better clarity, less echo, less CPU processing per channel? Anything other than price?

  2. I will apologize for asking this up front, as I have probably read 100 articles and websites on this topic, but I cannot find the information I am looking for. For one of my projects I am looking to receive and possible send SMS messages. I know support exists in Asterisk, but from what I read, it seems that most of it does not work for the US, which is where I am. I know there are SMS gateway services out there, but they all seem to offer more than what I need, not exactly what I need, and charge a lot for it.

To simplify what I am trying to do, assume I have a virtual office of 50 sales people, each with a mobile phone. I want to give each sales person a personal “office” DID line that can receive calls or SMS messages. for calls, I want to connect the sales person with the caller, for SMS messages I want to receive the message into a server, and then either email the sales person with the message or perhaps send it to their phone.

My thought process is as follows:

  1. I need to purchase DID numbers. I’ve setup a call center, and I have been through the process of getting DIDs, trnking them on a T1, etc. but SMS throws a wrench in my plans. Questions:
  • Do I need to buy a DID from a Mobile carrier instead of someone like Qwest? I know certain prefixes are “mobile” numbers, or at least used to be.
  • Does number portability cross land-line/mobile boundries? Can I go into T-Mobile and say I want to port my home phone number to my cell phone?
  1. I need to receive the calls and connect the sales people. This part I see no issue with. Simple PBX functionality.

  2. I need to receive SMS messages. NO idea how this is done, I understand about connecting to an SMSC to send/recv messages but:

  • Can I get a SMS message down a traditional T1 in the US?
  • Would say T-Mobile really peer with me, a lowly business man?
  • Are their carriers that are more small-business friendly?
  • Will SMS service providers, allow you to use your own (possible non-mobile) phone number to use their services, most web sites I read seem to say No.
  • Will VoIP/IP PBX service provides process SMS messages? I know the phones can do it, but I see no mention of SMS services on any of the popular VoIP providers websites.
  1. I need to send SMS messages. This seems tedious, but doable, Each mobile carrier has their way of sending an SMS from some API, I only need US support, and probably only need the top 4-6 carriers. So I just implement code for each carrier.
  • Unless I connect to an SMSC like above…

Thanks for any help you can provide,

Since you want DID’s you are much better off with a PRI T1 (even a partial). You can technically get DID’s with analog lines but its not nearly as straight forward as with a T1. There should be no difference in call quality between a good analog line and a good digital line. The main challange with analog is if you have 10 lines 5 could be good and 5 could be crap. With digital there either all good or all crap (if there crap keep on the phone company to find you a good pair and dont let up - there is no reason to suffer through a crappy digital line).

As far as SMS goes - in the brief amount of time I have looked into it it seems pretty hard to do in the US. Sounds like you have done more research than I have so I will leave it at that. You may fing some info on the following link.