atcomsystems.ca/forum Forums General General Telephone & Systems Information Multiple lines under one phone number

I have always been baffled by how hundreds of people can call a customer service hotline such as Xbox Customer Support and not get a busy signal when someone else is using the line.

I have a theory:

The company opens a customer service office and sets up their PBX. They rent a 800 number from the telco. The building the customer service office is located in currently only has one line coming in, so if Line 1 is busy any callers will get a busy signal. So the company calls the telco and wants more lines installed. The telco technician runs more copper/fiber optic cable from the Central Office to the company's office and assigns the same 800 number to all of them so someone is always available to help the customer.

Is this how it works?

You are thinking 1FB. DID numbers are not limited to one call. Any DID number can receive as many calls as there are channels or call paths available. Thats how 100 users can all have a DID number even though only a maximum of 24 can be called at any one time. Of course if the channels are all busy, the next call will get a busy even if the station isn't.

A little expansion on MNDAVE's post. Using POTS, the customer leases 5 lines, as an example. Historically, they were in order, ie XXX-YYY4 through XXX-YYY8. (It was a mechanical thing. Once the electronic CO's deployed, the lines were no longer required to be in order.) These were/are connected thru the magic of central office wiring (later, progamming) so that when the 1st line was busy the call was diverted to the 2nd line. If line 2 was busy, the call was diverted to the 3rd line,etc. This is called 'hunting'. Basic hunt group. There are other forms and 'wonderous' things that evolved from the basic hunt group. At any rate, a number can actually be assigned to all 24 channels of a T1, or 23 channels of a PRI. (Historically called a 'Terminal Hunt' group, because only 1 REAL phone number was assigned and if the lines were individual copper pairs, they were ID'd with 'Terminal' numbers for accounting and installation/repair purposes) Or, a block of numbers can be assigned to the T1 or PRI. AS for '800' calls, they can be a dedicated group of lines assigned to that number, or the 800 number can effectively be 'call-forwarded' to a local phone number. The dedicated group of lines, or the local phone number, can be part of a hunt group of copper lines, or a T1/PRI.
Now that you've got more than you wanted to know, 'at'll larn ya' not to ask too many questions! John C.

The replies above are most likely scenario. They probably have a T1 or T1's setup as a trunk group and they have hunting on that group. XBox might have a hundred operators I don't know but if they do then they need 100 call paths. That would be 5 T1s in a trunk group able to take up to 120 simultaneous calls before a caller hits a busy signal. Good question.

Wow! That's a lot more sophisticated than I though! Thanks for the knowledge.

To add to that, there are advanced toll-free services provided by the carrier that can split traffic different ways to a customer before it reaches them...for example, one call center may have 5 T1s, but the call routing on that trunk group may be set up with the carrier that overflow traffic is routed to a different trunk group that could have another 5 T1s at a completely different location.

Hi there,

What enables a successful customer service so no busy tone will be heard is with the use of a call queue found on some small business phone system