ATAs vs. IP Phones: Which should you choose?

September 17, 2009
Instead of using a customary ATA to convert legacy telephones or PBX equipment, some users of VoIP prefer to use a "pure IP" system and use IP phones. There are advantages to both methods. ATAs are the popular choice for the home user. Many home users want to mimic as closely as possible a typical POTS line in which another member of the family who wishes to enter the conversation may simply pick up a second phone. Telephones connect to ATAs using the same type of cables as they would to connect to a POTS line. One can easily connect an ATA to household wiring so that all phones may use VoIP. (Be sure to disconnect the POTS provider first.) ATAs are a very economical option and can be purchased for less than $50. With T.38, the second line of an ATA may be connected to a fax machine. Because of the popularity of ATAs, they are better known at the support departments of most VoIP providers. It's cheaper to put an ATA on redundant power; simply use a UPS. With IP Phones you'd need either one UPS per phone, or Power-over-Ethernet. IP phones are a popular choice for business users from home offices to large enterprises. With IP phones there need not be a restriction of a certain number of phone lines. The number of concurrent calls you may make are limited only by your available bandwidth. With providers that charge per minute, you may make and receive theoretically any number of concurrent calls during a busy time and not worry about expensive telephone lines during a quiet time. IP phones have several usability enhancements when compared to analog phones. Caller ID is delivered to IP phones instantly, not in between the first and second ring. IP phones typically provide higher audio quality. (The effects of this are most noticeable when making calls from IP phone to IP phone.) You may tap the hook of an IP phone and have it disconnect the call immediately without accidentally activating 3-way calling. When you press the Redial button on an IP phone, the phone may start ringing instantly without having to "dial". Visual call waiting may be silent with an IP phone. The voicemail provider may turn the message waiting indicator on and off mid-call. We also hear reports that say conference calls and speaker phones perform much better with an IP phone. It is even possible to write software for some IP phones. If your phone system requires some uncommon feature, you may build it, or hire a programmer to build it for you. There are plenty of happy VoIP users using both ATAs and IP phones. Consider the advantages of both and select the one that is right for you.