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What is the major difference of sending an 800 number over a PRI piggy-backed to a DID or sending DNIS?  I understand that in all cases without DNIS, dedicated access is not an option.  What if I had the 7 (800) numbers in our office sent down our T1 pipe with DNIS?  How do I program my Definity G3iV3 to accept DNIS and send it to the appropriate hunt group?  Or better yet, what will I gain other than Dedicated access?


I want to back up a little to answer your question.  Usually 800 service comes in two flavors, one where you have trunks that are connected to your long distance carrier (i.e Megacom 800 service for AT&T).  With the other, the 800 number routes the call using a local provider (i.e. 800 Readyline service for AT&T).  If you have dedicated trunks, you work withe the long distance provider on which number (DNIS) is passed in the ISDN setup message.  This is usually on a per 800 number basis, although there are long distance network features that can route to other DNIS numbers depending on prompting the caller or NPA/NXX routing tables (these are developed by the long distance carrier customer).  On the PBX, the DNIS can be an Extension, a VDN or a Hunt Group lead number.  
The second 800 service (800 Readyline)routes to a 10 digit number.  A call to this 800 number would be routed to CO switch that provides the PBX's local service.  It comes in like a DID number (the number that is provided to the long distance company for the 800 number routing must be in the DID range).  Depending on how your DID numbers are set up, ARS (for adding or stripping digits) may be involved.
To set up 7 different 800 numbers to seven different hunt groups, you would set up the hunt groups with 7 different hunt group lead numbers.  You would then get with your long distance provider.  If you have trunks connecting you with the long distance provide, you would give them the 4 or 5 digit hunt group lead number(DNIS).
If you are going to route the call through your local service provider, you would give the long distance provider a 10 digit numbers to route the call.  The ten digit numbers would be part of your DID range.  The last 4 or 5 digits (Assuming no ARS digit insert or deletion) would be the lead hunt group number.

Hope this helps
Leo V. Brown


So Basically DNIS is or can be any number or combination of numbers that I inform our provider.  Unless the number is directed to the LEC, which they would point to a 10 digit number.   Which way is better?


That would depend on your call volume, cost of trunks from your long distance provider and the cost per minute for the calls.  The rate per minute for Megacom 800 type services are usually cheaper than 800 Readyline type services (the reason is the long distance provider has to pay the local service a portion of the call revenue). While the per minute cost of the calls is cheaper, you have to pay for  dedicated T1 pipe(s).  If your call volume is thousands of calls a day, a dedicated trunking arrangement like Megacom may be cheaper.  If your call volume is in the hundreds per day, then having the call passed through the local carrier may be better.  
There is other factors that also come into play and one of them is distance from your long distance provider.  Many of the long distance providers charge per mile for T1 spans.  
The best thing is to sit down with a long distance provider and discuss their different options and costs.  Check out a couple of different companies because rates can vary.

Leo V. Brown


Can you pls eloborate more on the second type of 800# that you described in prev reply, I would like to understand it, I can't get much out of it from the above reply.



Leo, is it more effective to use DNIS digits versus pointing an 800 number to a DID?  Also, how does DNIS work.  Currently, I am pointing our 800 numbers to DID's coming to us from the LEC.  What do you think?


The 800 Readyline type service (AT&T's name for the service) points an 800 number to a 10 digit local number.  In effect, you could get a long distance provider to point an 800 number to your home phone.  
For a PBX application, a 800 number is set up to point to a 10 digit number on the PBX. This 10 digit number is in the DID range of the PBX and this case DID and Dialed Number Identification Service(DNIS) are the same.  DNIS is just a term to refer that incoming calls (via ISDN) carry a number with the call that the PBX then uses to internally route the call.  
If you call the 10 digit number instead of the 800 number, your call will end up at the same place.  
The hunt group lead number is 4567.
The DID Range 555-4000 to 555-4999.
The Area Code is 313.
The 800 number 888-888-1234.
When someone calls 888-888-1234, the long distance provider routes the call to 313-555-4567.
The Local service provider receives the call and strips off the leading 6 digits and sends 4567 to the PBX (this is the same treatment that it does with any DID call).  The PBX receives 4567 and routes the call to the hunt group.

With Megacom 800 service (again AT&T's name), you have dedicated trunks between your PBX and the long distance provider.   In this case the long distance provider does not need the 10 digit number but just an extension number to pass to the PBX (the extension number can be a hunt group lead number, VDN, etc.).  With Megacom calls, the long distance provider's 800 database contains information on where the physical location of the trunk connections (i.e. what network switch has the trunk group that connects your PBX) along with the extension number to pass down to the PBX.  In this case the extension number is referred to as the DNIS.

The hunt group lead number is 5678
The 800 number 888-777-0987.
The PBX is connected to the long distance provider's tandem switch 47 and trunk group 1445.
The DNIS programmed into the 800 data base is 5678.
When you call 888-777-0987, the 800 data base directs the call to switch 47 and trunk group 1445 and passes the DNIS 5678 to the PBX.  The PBX routes the call to the hunt group.

Sorry I confused you before.  I hope this is a little clearer.

Leo V. Brown


What Leo touched on in his first message is an important feature of DNIS that I'm not sure routing through the LEC can provide; a DNIS can be defined on a per NPA/NXX basis thereby allowing different routing based on the area from which the call originates.  

Like I said, as I've never gone through a LEC for 800 I'm not sure that routing through your LEC can't do this but this has been an invaluable feature that routing via DNIS has provided to me in the past.  In dispatch situations or even inside sales where specific agents in a group are experienced with or responsible for specific regions one 800 number can be used to route automatically to the proper agent thereby decreasing cost not only through more intelligent call routing but increasing customer satisfaction by automatically handing them off to the most knowlegeable agent.


You can set up routing within the long distance network based on NPA/NXX (or other routing criteria).  Again some of this depends on your carrier but several have these features.  With AT&T the feature is called Route-It!.  Route-It! can also be combined with other AT&T Advanced features to perform specific routing tasks.  
Lets say you have two hunt groups, one grouphandles all calls for Colorado and another handles all calls for Wyoming.  In the Route It! tables for your 800 number you can have it examine ANI of the incoming call so all area codes for Colorado (720, 303, 719, 970) are routed to one 10 digit DNIS and calls to Wyoming (307) are routed to another 10 digit DNIS or in this case DID number.  You can also prompt in the network but that can get expensive. You are charged for each call that hits an announcement (The instructions for the call prompting) and also there is a per minute cost for connection per announcement.  AT&T's web page gives an overview of the advanced features.  I used to be familar with Sprint and MCI but it has been 4 0r 5 years since I worked with their network features.

If you want to prompt the caller on a single 800 number, you may want to look into the Deluxe or Enhanced Call Center package for the Definity.  This adds Call Vectoring to the Definity and you can prompt in the Definity to send the calls to different hunt groups.  You can also do some routing on NPA/NXX by using vector routing tables.  If this is of interest, you can go to the AVAYA web site and download a couple of their call center manuals.  The link is: http://support.avaya.com/cgi-bin/gx.cgi/AppLogic+Elmo.
Select the ELMO ARCHIVE link, select the Document Number radio button and type 555-230-520 in the box.  This will bring up the EAS and Vectoring guide.

Leo V. Brown


Sprint & MCI both offer similar packages and charge for the front end announcements if you wanted to look at call prompting.  

I wouldn't go to prompting, though, whether it be in house or from the provider.  The point of using the ANI & DNIS together for call routing is to cut down on the amount of time spent in getting a call to the right person and, in turn, reduce overall cost by cutting down on the total length of the call.  A prompting scenario just adds time to the call when, really, your provider can narrow regions down to a specific area within a city or a specific county within a state that sends a particular DNIS and is then handed to the individual or hunt group that handles that area.  Now, that of course involves some database maintenance on the technician's part but I've found that once you set something like this up, the users won't hesitate to let you know when the routing isn't working properly.

You can do this even without vectoring but you add vectoring into the mix and you can do some really fancy stuff.


You guys hit all the answers.....Thanks.....

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