FXS, FXO, DID, DNIS, VoIP What plugs into what? 2

[AlanEvans]

The IT Department at my company has been asked to wear a new hat, Voice <puts voice hat on> and I am new to voice. Our first project is to create a VoIP trunk between our corporate office and one of our remotes sites.

At our remote site we have a Norstar 824 and I have spare parts pulled from a site that we just closed. Including 0x12 and 2x analog trunk module + 1 DID trunk module.

At our corporate site we have an Option 11 with no free trunks/PRI so we will have to buy something for that of course. I am thinking PRI to my Cisco 2600 then I get DID and Caller ID.

Can an FXS port from say a Cisco or Adtran router provide DID info to the DID lines of the DID trunk module? This way I can do 3 or 4 digit dialing from my corporate office? Or will corporate users be relegated to dialing a phony TN to get a trunk to remote location then dial extension?

I get:
[FXO Port] <---> [FXS Port]
[FXS Port] <---> Analog Phone

But how about these?
Router[FXS Port] <---> [Analog Trunk]Norstar824 ???
Router[FXS Port] <---> [DID Trunk]Norstar824 ???
Router[FXO Port] <---> [Analog Trunk]Norstar824 ???
Router[FXO Port] <---> [DID Trunk]Norstar824 ???

Thanks in advance.
-Alan

 

[PERRYPJ]

NO FXS,FXO ARE EITHER LOOP START OR GROUND START TRUNKS
FXS= SUBSCRIBER
FXO= OFFICE

OLD ROLMEN WORKING ON NORTELS

 

[CBasicAsslember]

First rule of design is to define what and how you want it to function. IMO the numbering plan is most important. All extensions should have the same number of digits. It is best if each site has a unique first digit. This will serve a couple of purposes. First it will make upgrading to a more sophisticated system easier in the future. Second, it will make it easier on the user as they will know which site the call is going to. A few questions to start:

1) What is Numbering plan for each site?
a. Number of digits in an extension number
b. Extension range (example, you might have four digit extensions on the option 11 that span 4400 - 4600)
c. How much traffic do you expect between sites at any one time?
d. How much data travels between sites? IOW, how much bandwidth do you need for data.

 

[AlanEvans]

CBasic:

I agree with your first rule, that's why I am posting. I think a valueable part of planning is knowing what you have and what you need.

Its slow going gathering all of the information you mentioned as our phones have been managed by the purchasing department until now. Yeah I know... I think that goes back to when each location had one phone that you had to reserve by putting your name on a list. (Probably only 6 months before I started in 2004.)

Further complicating the matter is that the company is split in two because the two brothers (privately held) can't play nicely in the same sandbox. As a result at our corporate location we have one Opt 11c that services 'upstairs' and 'downstairs'.

To answer your questions:
1. Corp = DID 8200-8299 with second line 42something (need to find this range still), DID 5900-5999 plus some other second range i believe
Site1 = 300-340, no DID
Site2(Not in project but planning for it JIC) = 400-499 DID as 6400 - 6499
Site3(Also not in inital project) = 200 - 215, really small I think 3x8 key system, non - norstar if I recall
a. See 1
b. Waiting on some electronic copies of our phone bills to mull over
c. 768K lines, typ 40ms latency with option for QoS, utilization is relatively low excluding bursts. (I use cacti to collect utilization from a lot of devices on the LAN, really useful)

 

[acewarlock]

I don't often say this but I think this project is beyond the scope of this Forum and your ability. You should call a Nortel Partner. I've been doing this for more than 25 years and I would call a Vendor for this.

 

[CBasicAsslember]

I am with acewarlock 100%. Input from a qualified vendor will be invaluable to you, and at least initially, will only cost you a little bit of time.

Caller ID:
With the 8x24 caller ID is not really an option. It was available for a time but you would have to locate a used caller ID box for the 8x24. The system has been discontinued for over 10 years now. The best your going to do is a pseudo caller ID. You will know, by virtue or the trunk/station the call comes in on, what branch the call originated from. The set the call originated from will not be available.

VoIP:
Approach with extreme caution. A common myth is that voice “is just data”, it is not. When transferring data the order the packets arrive in is not critical, with voice it is. Data utilizes hand shaking to insure that lost or corrupt data packets are resent, time constraints make this option unavailable for voice. The bottom line is IP was not designed for voice. One of the arguments for VoIP is cost savings. Those savings may or may not be realized when you consider the hidden cost of the extra time needed to maintain the system. Voice quality and reliability must also be factored in. One of the myths I run into is, because VoIP new, it is better. At the very least people seem to believe that they will get the same product at a lower cost.

Considering the above I would recommend the following on experimental basis.

Option 11 500 set ports <--> FXO <--> 768K line <--> FXS <--> Norstar 8x24

Set up as many lines as you will eventually need and program the routing so that calls to this office will go over the VoIP lines. Make it clear to the powers above you that this is just for evaluation. There will be minimal costs as you seem to have the equipment that you need already. It will also serve to CYA. IMO there is a high probability that you will have, at the very least, intermittent voice quality issues (this will of course depend on the call and data volume). Let the powers that be make the costs/benefit decision as to whether the savings are worth the probable loss of quality.

 

[AlanEvans]

acewarlock:

Way ahead of you. Meeting with our vendor on Monday. I may be ambitious but I am not a dummy.

Thank both of you for your thoughts. I think I am all set until my meeting Monday.