IP Phones

IP Phones

Now that you've decided to go complete to "IP" as your network of choice - for data and voice, maybe it's time you dumped that old analog telephone and migrated to a VoIP phone that can not only plug right into your broadband router using Ethernet (10/100 or 10/100/100Mbps) instead of that old RJ-11 phone jack.  Not only is the connectivity much faster and easier, a VoIP phone can also integrate with your data applications to do some "neat" stuff like display your Outlook contact information on the display and much, much more. 

But, before you run out and purchase one of these slick new phones there are a few things we think you should consider.

• Call Control - what systems and/or protocols does the IP phone work with?  If it's just with a specific vendors IP PBX platform - you'll have to have that software/hardware for the phone to function.  If however, it supports SIP it may (as with any standard SIP - Session Initiation Protocol - phones sometimes don't  work quite as expected - check to make sure it will work with your systems/equipment before you buy!) work in an "open" IP telephony environment.
• Codec Support - the most common codecs (analog to digital conversions) include:
  • G.711 - 8 bit compressed pulse code modulation sampled at the rate of 8,000 samples per second creating a 64Kbps bitstream
  • ADPCM - adaptive differential pulse-code modulation, converts sound or analog information to a digital format
  • G.729 Annex A - processes signals with 10ms frames and has a 5ms look-ahead resulting in a total of 15ms algorithmic delay, input/output is 16 bit linear PCM samples that are converted to 8Kbps compressed data stream
  • G.729 Annex B - provides a high level description of the Voice Activity Detection (VAD), Discontinuous Transmission (DTX) and Comfort Noise Generator (CNG) algorithms.  The algorithms are designed to reduce the transmission rate during period of silence during a conversation.
• Connectivity - Power over Ethernet support is a good thing (you won't need a separate power adapter!), and in addition to a standard Ethernet (10/100 or Gigabit) connection, a connector for a headset is a good thing as well.

• Display - An IP phone should have a readable display - why?  Because at some point you're going to find your voice and data applications coming together and you'll want your phone to be able to display "extras" like contact information and results from simple data queries.

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• Extras - As with any phone, the "extras" can "make" the phone.  Look for things like message waiting indicators, feature keys, programmable buttons, fixed feature buttons (for things like speaker, redial, conference, transfer, hold, voice mail, etc.) and easy navigation arrows/wheels.

As always - price is very important too!  So make sure the phone you purchase meets the demands of your pocket book as well.

That's about it!  Let's take a look at the Voice over IP phone options that are available to you.  Detailed information is available in our product matrix at IP Phones.

IP Phones Review

"IP" Telephones"*

(Rankings - best, 5 symbols, worst, 1 symbol)

* A = Amateur, R = Rookie, P = Pro

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