A lot of present IP telephony solutions seem, as far as I know, to be just as proprietary (for special features) as the traditional systems. IP is all great and wonderful, there's inherent QoS / CoS and so on, and it leverages the 'single-cable-to-the-desktop' theory.
But if you buy into, say, a CallManager solution from Cisco, you're stuck with per-phone licensing and SCCP, although there are ways to ensure interoperability between Skinny and non-Skinny environments.
I know from having done a minor project on an Asterisk-based IP PBX that a lot of the functionality and ease-of-use (soft buttons for vm, etc) depends on the equipment you buy. I was using Cisco endpoints with the Asterisk PBX, and with the right configs, the soft buttons worked fine. That said, I used only one model of Cisco IP Phone, the 7960, and not anything else. I also have to point out that the softphones were simple to setup, and I am not familiar with a traditional digital PBX that offers a softphone.
With Asterisk (more specifically, TrixBox, which is a pre-rolled Asterisk-based implementation) I had parking lots, queues, voicemail, 411, music-on-hold, conference calling, customised logos for the phones, custom ringtones, xml / web data delivery to the phones, support for analog lines and/or T1/E1 trunks, voicemail-to-email... the full list is here.
Just need to research the implementation and equipment thoroughly before putting it in place. It is perhaps, in that respect, more akin to a data job than telecom, as there is so much variety you need to be sure what you are buying will do what you want. So no, it isn't for lack of features that IP telephony may be behind. I'd put in an Asterisk box anytime before a Meridian-class system based on what little I have seen :) |
