To start off with, I work for an Avaya Business Partner. We also do Nortel but won't touch the Cisco Call Manager except to integrate to it.
As far as picking a PBX, it really depends on your Business Model needs. Here are some items to address.
Don't buy into the Cisco "Voice is just another application on the network" sales pitch. They want everyone to look at it this way so that you will spend a whole lot of money to upgrade your network to support the VoIP deployment and then add the Call Manager application on top. Do you really need to upgrade your network and if you go Avaya how much of an upgrade do you need on the network?
I have a customer that is 100% Avaya. Cisco has been trying vey hard to get in. The customer has a Cisco network. They were going to try out a Call Manager for one of the small office deployments. It looked like a viable solution since they had to put in a router anyway so the cost would just be the addition of the Call Manager/Phones. I asked them if they went with an Avaya Media Gateway would't they be able to use a smaller router since it wouldn't have to support the DS1's for voice? A light went on. Also, if you went with the Cisco solution and the router went out wouldn't you lose both your voice and data? With the Avaya solution and a Local Survivable Processor, a WAN outage simply results in the gateway failing over to the Local Survivable Processor for continued operations. It is also the elagant solution (unlike SRST you have full feature functionality). If the Avaya Media Gateway goes out the network is still up and your IP Phones can still use the resources at the main site. The only loss is DID service.
Now let me state, that this doesn't mean that it is the solution for you. Again, you have a business model decision to make. You need to get proposals from both sides. If the data team is saying that they need to upgrade the network equally with both solutions, then it's time to bring in Juniper/Exreme/Foundry/HP/anyone else and fire your data team since they clearly don't understand VoIP. If SRST is good enough for survivability then so be it. Most customers fail to clearly define what it is they need and what they want. That means the vendor gets to take the lead.
Either way, your data team will probably need to be educated on what QoS is. Auto QoS is nice but doesn't complete the picture. I have installed hundreds of thousands of IP Endpoints and have only ran across 2 or 3 really strong data teams that know what Real Time traffic requires and get it right in round 1. If you think that doesn't mean you then get off your horse. I'm not talking about a bunch of mom and pop shops but a significant number of Fortune 500 companies. The best analogy I was ever given was by a customer who said "I didn't realize when we deployed VoIP that I would be putting 1500 network sniffers out there". The reality is that applications work with 500 ms delays but Toll Quality Voice on a VoIP network doesn't no matter what solution you purchase.
YOU WILL NEED MONITORING TOOLS. If you go Avaya the bare minimum is to deploy the VoIP Monitoring Manager. Having the loss, jitter, and delay statistics in black and white will be the only way you can convince the data network folks they have a problem. You also need to be very specific if you are negotiating WAN contracts. Not all WAN's are created equal and not all WAN's support class markings. CNA is a great tool for muti-site deployments but also costs.
Cisco is fine for administrative staff. DO NOT MIGRATE OFF OF AVAYA IF YOU HAVE A CALL CENTER. It might just end your employment. Cisco is in no way equal to Avaya in the call center arena. Cisco went out last year and finally purchased an IVR company. They have a dialer which I believe is the old Geotel Peripheral Gateways reworked to support outcalling. If Cisco is proposing a call center solution then get 5 references of equal size. Compare the funtionality of the phones, ease of programming the call routing, capacity, and reporting.
Ask the question, how long does it take you to do an upgrade. I have personally done four Avaya S8700 systems (8 media servers and 11 LSPs) in one night.
Don't forget voicemail. Both Avaya and Cisco have "UM" products. Unfortunately, nobody has clearly defined what UM actually means as far as a feature set. Compare the products. Avaya supports integration with various vendors voicemail system. Does Cisco? (FYI, you can actually network a Cisco Unity into an Avaya voice mail network if you have use the Microsoft VPIM connector and the Network Messaging platform).
Ask for a deployment plan. The Cisco deployments that I have been aware of last years (large enterprise customers).
FORGET SIP. Why lose functionality by going SIP. If it is a requirement then purchase Avaya IP Phones that can be converted to SIP such as the 4610, 4620, 9630, 9640, and 9650) NOTE: I believe the software for the last 2 won't be out for another couple of months. Ask about SIPPIT-19 testing/certification.
For both vendors. Have a support contact addendum included that provides the next 3 years upgrades (including all material and labor).
Get a quote from an Avaya Business Partner and not just Avaya.
What is the migration plan for both Vendors?
What components are going end-of-life/end-of-support. As an example, if you have any SCC cabinets then you need to replace them with G650's or Media Gateways since end-of-support is not far off for the SCC cabinets.
Who is going to support the product. Ever have a Cisco technician show up on site?
Provide Service Level Agreements for Warranty item replacement.
Have both vendors quote 3 years support for software only and for software/hardware combined.
How many of the vendors technicians are within 100 miles of each location (determines if you can expect same day service).
There are different ways to configure the systems for levels of survivability. Clearly define the survivability requirements at each site including call center functionality requried during a failover. Have the vendor walk through WAN failure, Network Failure, PSTN failures.
Don't forget that you have analog devices such as FAX and Modems. Can the Vendor support T.38 FAX? What modem speeds can you expect in the VoIP environment. If you only have one or two modem lines that having to get a couple of 1FB's is not big deal. Getting 150 is.
Make sure to look at any current peripheral items such as CTI applications, wallboards, montiors, IVR, Dialers, Recording etc... to see what will need to be upgraded. Have the vendor provide compliance documentation.
What training is required to become proficient on each system. If you go Cisco, how many additional data folks will you need to hire? Same for Avaya?
These are just a few of the questions you need to ask.
James Middleton
MCSE/ACE-Implement:Enterprise Solution Architect
James Middleton
ACSCI/ACSCD/MCSE
Xeta Technologies
jim.middleton@xeta.com