foandoc

Things to watch out for:
Redundancy means two call manager servers with the associated UPS's etc. I've got 6509's on the edge and in the core. Powered blades on the edge required 208 power., not 110. Edge boxes also need UPS's etc.
The ROI numbers batted around in sales pitches are complete bull. With Smartnet costs on 6509's (i've got ten) to be around 10K a year (redundancy requirements), my data network is rather expensive to maintain. My Option maintenance is about 10K a year (switch to desktop).
Mainteance visits by my network intergrator are $220 an hour. My traditional voice provider would cost me $75.
Cisco TAC has come a long way but they still don't understand voice issues. It takes half a dozen emails to straighten out the confusion about hook switch problems on 7960's.
The greatest danger is techs on the data side. They don't have a problem rebooting servers without thinking about possible ramifications on the voice side. With the data base relationships between Exchange, AVVID, unified messaging and the like being so tightly intergrated , any minor "adjustment" on an exchange server could cause hours of trouble shooting on the voice side (trust me; I've pulled all nighters rebuilding servers because someone upgraded exchange without researching the field notes).
I've been saying it for years: VoIP is the data side raiding historically stable budgets. IT needs another source of revenue and they found it in voice.
Then there's the constant monitoring, secret prayers to the phone god that our firewall keeps out the badguys and now, the privacy/wiretapping issues.
VoIP works, dial tone sounds the same etc. Now if I could just get Nortel to act like a phone company instead of a Cisco wanna be.
I'm thirsty.

telecom116

I've got several VoIP systems going, so I'll present them if anyone has questions, then my take on things.

We opened a new data center 8 blocks from our headquarters this time last year. We were able to lease a pair of dark fiber from the City Utilities (plus we will have a gig microwave backup this year) and have 8600 core switches at both locations, so bandwidth and QOS is no problem. Management looked at a remote IP cabinet off the host 11c before choosing a standalone 11c with ITG trunking and TDM phones. I don't think our provider was even pushing us towards the IP line solution.

I also have three (soon to be 5) Nortel RLC/9150 systems (TDM phones with IP between the switch and remote site). Two (soon, four) of the systems are on the Gig fiber loop we're building; one is on a frame link.

This fall we evaluated our small rural branch banks for IP systems. All but one had Norstars, but with Nortel just getting the analog IP gateway out (too late for us) we went with the 3Com NBX. I really wanted the BCM, but for the cost of two of these we got NBXs at all of the five sites, plus a SS3 NBX to offload the VoIP to a T1 in the 11c. We reused all of our old Norstar phones on all systems (that was where the savings showed up). We have a 3 Mbps Ethernet link between the five branches and the data center (power company fiber to every building) from 130 to 200 miles away from the data center).

My opinions:
If you want reliability, have only one physical building you are feeding, and have the data network and the PoE in place (or easily accomplished), I would do the Nortel ITG line solution. I probably could have saved one card slot in my switch if we had done that. TDM is still, by far, the safest way of doing things in a critical environment. I used a shared wiring conceprt (data room patches from the MDF to desktop). In a banking environment with the number of tellers, high school and college student and workers destroying your equipment on a daily basis, you want to go with something you can replace as a commodity. Plus, security and that it will work all of the time is a major plus.

If you have the bandwidth and multiple switches, ITG trunking is the way to go.

The 9150 is good solution for survivability out at branch sites (IF you have BRI available), something you don't have with remote IP phones hanging off a central site. (Notice I'm getting rid of my telco data circuits and going with fiber where I can...now you know why :wink:

BCM - not cost effective for 16 or less phones (small branches). Too much overhead. I already have a router at the site. I don't need IVR; I've got a central one. I don't need a call center; I've already got a central one All I need something that can do 6 to 12 analog trunks (no digital trunking available), 12-32 phones, voice mail and IP trunking. If Nortel had just designed some sort of IP gateway for the MICS that could use the ITG trunking protocols... The BCM (price-wise) just doesn't scale well in my business environment.

3Com - we've have had issues and complaints with echo (involving the third-party Norstar interface) that we believe to have resolved. Mostly due to handset volume and CO line power issues, Still evaluating whether the "fixes" from 3Com will work. Quickly learning to dislike 3Com's licensing as the newest s/w version requires an upgrade fee (three months after installing the system), and each new IP phone requires a license (unlike the old 3Com IP phones)