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New Member

Need some suggestions for office setup..

I have a client that wants to setup voip for their office.

They want to setup 5 IP phones. Each with their own extension for calling each other. But each phone needs to use the single outgoing connection to the PTSN network. They have a Cisco 2611 Router. What Modules would they need? Software? Callmanager?

Is it even possible to setup voip for internal use like this, but then able it to go outside using only 1 ptsn phone line?

Thanks for your help..


Re: Need some suggestions for office setup..

You would need the Call Manager software, a qualified server to run it on if you did not purchase it as a bundle and the module for the 2611 depends on what kind of connection you have to the PSTN. Analog? PRI?What?

It is very doable to have a setup like this with the one outgoing phone line but a bgger question is why? What are you gaining by having an IP phone systems with only 5 users as opposed to hanging 5 phones off of the connection to the PSTN? Unless the 5 users are not in the same office I am missing what the benefit would be when weighed against the cost, time needed and effort required to rollout and maintain an IP Phone system when all of your outbound calls are going over the PSTN anyway. I am the last person to try and talk someone out of buying some Cisco gear but I don't see the rationale behind chosing this route. Can you elaborate on why they want to do this?

New Member

Re: Need some suggestions for office setup..

For 5 phones you could run the Keyswitch software provided by cisco on the router. This will enable you to have you 5 phones with extension and on outbound liine. You would need the correct card on the router with the NM-2V card with the pri or fxo card. This allows you to use the router as the call manager and setup phones with speed dials.

New Member

Re: Need some suggestions for office setup..

Travis: I totally agree. But the Manager there wants to "commit" to the future of the company. (Plus I think he read it in a Magazine, so sad). And right now he has the budget to do this, so I figure okay if you really want it, let me go find out some information.

rwykoff: That sounds even better then using the callmanager server. Since their is only 1 outgoing ptsn analog line, I'm guessing the nm-2v with a fxo card. Then just get 5 ip phones, and get them setup on the network with correct extensions, and all with same outbound line.

If I did run call manager on a server, is it possible to run cisco's unity software on their as well with this type of setup? ie. Have the system also act like a voicemail server, and forward messages into outlook with exchange server.?

Thanks for your help guys, I really appreciate it.

New Member

Re: Need some suggestions for office setup..

I would have to say that you should go with the ios key switch. for only 5 phones this is a very acceptable solution. plus they phones and gateway cards that you purchase will work with a full blown call manager. If you boss still would like to have callmanager Cisco does sell a version that is ment for 100 or fewer phone. it has all bells of a regular version except you cant expand the system beyond a publisher and a subscriber.

hope this helps


New Member

Re: Need some suggestions for office setup..

Scott, That sounds good to me.

I was thinking of implementing this into a 2611 Router. Is the NM-2V the right module, with a FXO Card the right solution?

Also, I'm thinking that the 2924xl switch that we have here, is enough to put the phones into, and then the FXO card to the one analog pstn for outgoing calls.

Does that sound about right?

Re: Need some suggestions for office setup..

First to utilize ITS ( IOS Telephony Service) you must purchase the license for the software ( same as SRST ) for your router 2611, second, you must have enough memory in the router, I believe you need 16 flash, 32dram mim. Then you must configure and provision the router for the PSTN POTS line which would connect to the FXO port, The C-Voice NM will support 2 VWICs, I would suggest 1 FXS and 1 FXO ( this gives you 2 ports of each). You will then need cisco IP Phones and the 2924 switch will work fine. Please keep in mind that ITS is not Call Manager and features are limited in ITS. As for Voice Mail, ITS can connect to a unity server. All this hardware can be utilized in a full blow Call Manager enviroment.

Hope this helps.


New Member

Re: Need some suggestions for office setup..

Thanks for the info Todd.

One more question. If all 5 phones are connected,and each one has an extension #, Can I make it so all 5 ring when a call is incoming thru the FXO port on the router?

Basically I need to setup the phone so that they a) all can talk to each other with conferencing, b) Need to be able to answer the pstn phone line from any phone (ie rings on all of them).

Is that possible with Call Manager or ITS?

New Member

Re: Need some suggestions for office setup..


we have a great experience with ITS and I must say it is a really interesting feature of IOS for SMB or small branches.

The new version of ITS coming out soon will have many new features, I'd say 99% of what CCM does.

Concerning your project:

- We've had many problems using analog lines so I'd suggest you to switch to ISDN lines if possible. If not ... go for the FXO !!

- We have developed several products for ITS including a Voicemail Software (less features than Unity, of course, we're not competing with it, but also much lower cost and complexity). You can find all info and downloads on

- Concerning making 5 IP Phones ring toghether, you have several alternatives

- 1 - Make a shared line but if 1 person uses it nobody else can use it. By the way, if you have just 1 PSTN line it might be ok

- 2 - Next release of ITS will support Call Pickup, which in many cases is ok

- 3 - Another opportunity is to use a TCL script which makes phones, even with different numbers (no shared line) ring toghether. We've created TCL Scripts that perform this feature but there is a limit on the number of phones ringing toghether to 3 !! What we did is to develop TCL scripts that welcomes the caller, rings 3 phones, plays a message and finally makes other 3 phones ring.

- Finally, with ITS you can conference up to 3 phones at the same time with G711. You can add other phones in a sort of "chain"

ex. A calls B -> B conferences C (Conf. ABC) -> C adds D to the conference (ABCD) -> D adds E -> (Conferenece ABCDE) The matter is that if B leaves the conference, the chain is broken, A is out and CDE keep on conferencing.

I hope I was clear enough (quite strange example).

I hope I could help you, let me know if you need any other information

Best regards


New Member

Re: Need some suggestions for office setup..

ITS is in controlled release which means each deployment requires the approval of the product management team. ITS is not supported on Classic 2600 (2610, 2611, 2613, 2620, 2621) because of memory limitations. Use 1751, 1760, 2600xm, 3700. ITS 2.1 needs 32 flash and minimum of 64/96 dram (1700/2600XM).

I would suggest engaging an authorized Cisco IPT partner. If you are an authorized reseller I would consult a Cisco Channel SE before moving too far down the ITS path.

If this is a trial before implementing a larger solution you should consider CallManager (maybe ICS voice bundle) since most ITS features operate differently from CallManager and the user experience will be significantly different. Someone commented above that ITS is re-deployable as part of a CallManager implementation and that is true (assuming appropriate licenses have been acquired). ITS license becomes SRST license and ITS phone license becomes SCCP phone license.

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