Directory Number Planning

cyoungblut · ‎03-06-2007

We are getting ready to implement a new CISCO VoIP system with CCM 5.0 and I have a question on directory number planning. The group of D-I-D numbers that is assigned to us begin with 08xx - 09xx. Not my first choice but what do you do. I don't want the new extensions to begin with 0 or 9 but I would like them to match the D-I-D number if possible. Perhaps I'm too hung up on that. My choices it seems are to stay with the same 3 digit extensions currently in use and just assign the new D-I-D numbers to those 3 digit extensions (they won't match) or to go to a 5 digit extension which would begin with a 2 (example 20850) but I really don't want to do that either. What are your thoughts/recommendations on new directory numbers. The new dn's do not need to be the same as what they are now. I have already told employees they probably won't be. Thanks for all your help - this is all somewhat new to me.

Chris Deren · ‎03-06-2007

Well, how many location are you going to have at the end? When designing a dialplan you need to take the entire enterprise into consideration.

How many digits are you planning on using inter-site and intra-site?

If your plan is to go to 5 digits than, I would recommand getting 5 significant digits from Telco instead of 4 and using all 5 digits for DNs.

I guess what I am trying to say is, provide as much information as possible. Tehnically with digit manipulation you can do whatever you want, the critical point of dialplan is to make sure that it's straight forward for all end users, and allows you to grow.

Chris

cyoungblut · ‎03-06-2007

Thanks for the response - this will be a single site install. I don't see us adding any additional sites in the near future. It is possible we could do something with a "parent" type organization long term that is currently utiliziing 4 digit extensions. As you said - I want this to be strait forward for the users. Initially we were planning on brand new 3 digit extensions but my thought was to go to 4 in case we ever did anything with this other organization.

Chris Deren · ‎03-06-2007

OK, 4 digit seems like right choice, the only drawback to using the 4 digits of your DID block it the first digit "0", which typically gets allocated to operator. If your users do not dial 0 for an operator, you can use the extnsions with the 0, if you prefer to use another first digit than simply add a translation pattern that translates from 0XXX to YXXX where Y is the desired digit.

This translaiton pattern would be assigned to a parition that only the CSS assigned to voice GW has access to, this way all calls coming from the GW with DNIS of 0XXX will be translated to YXXX, and delivered to the phones. At the same time users can simply dial YXXX internally.

HTH,

Chris