December 19, 2017

IP Centrex is yet another way for your organization to get the full flavor of IP telephony without investing in a private branch exchange (PBX) or going crazy with softswitches. This is an ideal approach if your organization wants the features of the PBX but none of the complexities.

IP Centrex Advantages

It’s a real Centrex setup with all the features, bells and whistles typical of a PBX phone.

The entire organization, no matter how far flung geographically, gets the same telephone service.

Network charges go down because the phones run on broadband IP connections.

IP Centrex Disadvantages

It is not cheaper than regular Centrex.

The phones are as moody as your data network.

The phones work with particular IP Centrex vendors – switching service providers isn’t easy.

Centrex solutions are not new. Basically what Centrex does is enable is a PBX phone without a PBX. Let’s look at an example to illustrate the possible advantages. One professional wanted a regular business phone in every room at his home so he could pick line one or line two whether he was in the living room or in the home office. He got his wish with four phones at $400 each, installed by the local phone company.

The upside – using the phone makes all the difference in the world with call forwarding, voicemail, and other features.

The downside – this setup requires a distance sensitive ISDN hookup, which can add up to $200 a month just for local access.

Now imagine this same setup, but with IP phones taking the center stage. The major difference here is in the feature set. Besides doing all the regular things business phones do, an IP phone can synchronize voice mail with e-mails so messages can be listened to online, or have a multimedia function where the phone would function as the voice part of the videoconferencing setup.

The biggest advantage is that telecommuters, salespeople on the road and folks in the headquarters can have identical phone service regardless of where they are. Remember the $200 ISDN bill mentioned in the above example? That’s gone now, with a regular broadband connection being the alternative. And on top of it, all intra-company calling is free, since these calls don’t have to touch the traditional telephone network.

However, the biggest advantage of the IP phone is its Achilles heal. How often does your cable modem go out? Would you be comfortable with your phone having that many outages?

Of course, this is not a totally fair way to judge IP Centrex offerings – only a fraction of U.S. businesses rely on cable modems for connectivity and most businesses have reliable broadband pipes that comes with a couple of “nines” of reliability.

Still, data networks are generally less reliable than phone networks and this is a minus. Another point is that IP Centrex vendors display none of the interoperability characteristic of IP. Meaning IP Phones sold to work with a particular IP Centrex service won’t let you switch IP Centrex providers easily – a potential pitfall.

© 2017