Trunk Overflow

[baschul]

I am an NT/Cisco engineer for a medium-sized company. The person who has been responsible for the definity phone switch and voice mail quit a couple of weeks ago. I wa told that I would be responsible for it from now on. I understand most of the basics from the books and the online help, but there is a problem that I need to correct asap and I do not know where to begin. We have had complaints of busy signals from people trying to call in to our office unless they are dialing one of the 800 numbers.

Trunk group 1 is a CO group with 14 two way lines. Trunk group 2 is a DID group with 8 incoming lines. Trunk group 3 is a tie group (T1) to AT&T for long distance/800 access.

The long distance/incoming 800# calls are getting through on trunk group 3. We are not having a problem getting an outside line due to the fact that we have 14 two-ways on trunk group 1. When someone tries to call in locally it comes in on trunk group 2 (8 DID lines). Once these 8 DID lines are all occupied, all other calls get a busy signal.

I am told that when the system was first set up, the 8 DID lines used the 14 two-way lines as an overflow. I have no way of knowing that this was ever really set up this way or not. I would, however like to know how to set this up so that when trunk group 2 was full, it would roll over to trunk group 1.

Is this a setting on each individual trunk group or does it have to do with the route-pattern setup, or something else completely?

I would greatly appreciate any help that anyone out there could provide.

Thanks,

Brian

 

[netcon1]

That configuration will not work efficiently.

The DID trunk group is for incoming calls only. You could have your Bell carrier overflow the calls to the 14 trunks in trunk group 1 but that will not work as the calls will just blast the one incoming destination in the trunk group.

What you may want to do is re-engineer the T1 service and make it a PRI/T1 service and put the DID numbers through it. That way the 800 services, the did numbers and the outgoing calls can contend for the 23 channel on the T1/ISDN pipe. The outgoing calls could be routed over the copper first and then the T1/ISDN so it does not impact the incoming calls, and the incoming DID's and the Incoming 800s can then both share the T1/ISDN pipe. No blocking will occur as you have line sharing for incoming calls.

Also make the T1/ISDN pipe overflow to the 14 copper lines so that if the T1 were to go down, then all the calls will overflow to the 14 coppers in your switch.

Cancel the DID trunk circuits and move the DID numbers to the T1/ISDN circuit. This will save you in trunking charges.

This would be a better way to share resources and reduce costs on your telco services.

Netcon1
(Mark if useful!!!)

 

[baschul]

Your suggestion is what we would like to do eventually. I have been asked not to make that kind of change just yet. I was told by my local telco just yesterday that they could not roll the did overflow to the other trunk group. They said that I would have to do it on my switch.

As a temporary fix, for incoming calls I would like trunk group 1 to serve as an overflow to trunk group 2.

Let me know if you know how to do this.

Brian

 

[mottelecom]

Contact your local Telco and have them set up the roll over, as they would be the only ones capable. The Definity cannot rollover DIDs to a separate trunk group without intervention from the CO. Simply put; if the call is getting a busy before it hits your switch, the switch cann’t tell the call what to do.

Good Luck,

Casey

 

[mottelecom]

Contact your local Telco and have them set up the rollover, as they would be the only ones capable. The Definity cannot rollover DIDs to a separate trunk group without intervention from the CO. Simply put; if the call is getting a network busy before it hits your switch, the switch won't have the chance to roll the call anywhere. I agree with Netcon1, install a 2-way DID T-1 and route local/toll-free outbound traffic and DID traffic on that T-1.

Good Luck,

Casey