The question: Is there a benefit to running VOIP on the internal network?
Many phone vendors will push for a hybrid approach to a new IP PBX which allows for digital phones at sites where there is existing cabling such as CAT3 so as to not have to incur the cost of re-cabling for VOIP. In this scenario, VOIP traffic is really traveling between sites across the WAN and not actually inside the site.
Some benefits of this approach are that:
You don't need to re-cable the site. You can use existing wiring and digital endpoints. You don't need to worry about powering IP endpoints via a PoE switch or plugging them in directly for power. And you know the sound quality will be excellent because it's the good ol' tried and true CAT3 infrastructure thats been used for the last century.
But this is the present. What about the future? We all know that one day VOIP will become the norm. Inside, outside and everywhere. But let's stick with the present for now.
As I know the benefits of this approach, what I'm having a hard time with is the downside. Will I be limited in the future with this design? Will I incur the cost of re-cabling to bring the infrastructure up to par to support VOIP inside remote sites in the future anyway? Currently, IP PBX systems will provide the same functionality for endpoints whether they're digital or IP. Except you just can't pick up a digital endpoint and relocate it and have the same extension like you can with an IP set.
So...what about the internal network? If you're running a true GB network with PoE switches configured with CoS/QoS, why wouldn't you go all IP on the inside? Also, what's the real benefit?
These are some of the questions I've been asking myself over and over so I don't make a mistake in spending a quarter mil on a system which might be obsolete in 7-10 years. Perhaps some of you are in the same boat. I'd love some comments and feedback.
Do you have the answers?
~TT