atcomsystems.ca/forum Forums General General Telephone & Systems Information DID and DNIS

No problem.

The ones you rang out that went to a dedicated group was either private CO line groups outside the main group or if you dial any number not assigned it will go to a dedicated point..usually the operator. I just had a customer that was getting spammed by an Awards Claim company promising a free Ford truck by calling back the 800 number and giving a claim number. Any unassigned number was ringing the operator. They had 400 DIDs and roughly half were unassigned. She was getting probably 200 calls a day. I took the DID table and sent all unassigned DIDs to a mailbox that says "Quit calling you worthless spammer."

RBF,
Thank you very much!

Justbill, You have it right. DID (direct inward dial) just hit a trunk group to a pbx and the pbx would complete the routing. The caller could dial digits if they knew an extension numer once they hit the pbx. The deal is, the number of DID's can be more than the number of actual trunks terminated to the pbx. Hence a block 100 DID's don't need 100 trunks to teminate to.

DNIS (dialed number identification service) dumps the last 3 or 4 digits of the DID automatically, although any digits can be sent.

I don't recall ever seeing anything other than digits (0-9) being sent as DNIS. Although I've seen * and # sent as the start and stop to some pbx's that use FG-D protocal with DTMF.

How would the PBX know where to dial unless it received identifier digits? The only digits dialed by the caller is the direct number..not any numbers after the PBX answers. What you are describing is DISA or auto attendant where the caller dials digits after answer to direct the call.

Ya know I've been doing google searches for a good down to earth type explanation and what you've said is about what I've found on the searches. DNIS is a DID that dumps digits after connected to the customer switch. I think I'm going to quit now, because I thought I knew and now I know I don't know what I thought I knew, but tomorrow is a new day so maybe I'll know tomorrow who knew what today.

:rofl: RBF, HaHa, If I did something like that the next call would be the CEO of the company mis-dialing one digit and hitting the smart-ass recording!

All DID and DNIS calls are routed after the PBX answers. The CO is pulsing a DID number or a DNIS number on a trunk that accepts inbound digits. The PBX then directs based upon info received.

Any digits can be sent by the carrier as DNIS, not just the last digit of the DID. I didn't mean any random digits. For example: you are using 3 digit dnis. Two of your DID's end's with 123. This causes a conflict with your routing. So you have the carrier send a different dnis number on one of the DID's.

Right. In my first statement it said DNIS was sent outside the DID block numbers. They have to tell you what DNIS they are sending since you already know what your established DID range would be. It does have to be different.

I got the OK from the big guys. At first I set it up to hit a mailbox that blind transfered to the 800 number. So everytime they called my customer it called them back on their 800 number. After scratching heads we figured that might be considered harrassment so we just went with the announce mailbox and hangup.