Ask Mr. Andrews: How Do I Select the Right ATA?
Q: My VoIP Service Provider Allows Me to Bring My Own ATA, Which One is the Best?
A: Thanks for the question, but your questions should really be,
“What is the Right ATA For My Situation?”
Most VoIP service providers do a poor job of explaining the differences and benefits of the different types of analog telephone adapters (ATA). Many take your level of knowledge as it pertains to telephone adapters for granted; assuming you fully understand each feature/ functionality of an ATA, and that you understand how these features/ functionalities relate to your calling situation.
What follows is a quick guide to selecting the proper ATA for your VoIP Service.
What is An ATA?
An Analog Telephone Adapter (ATA) is a device that converts analog telephone signals into digital packets for transfer across an IP network. Analog Telephones (small office key systems can also can access to VoIP through an ATA) connect to the the ATA via an FXS port and the ATA connects to the IP network via an RJ45 port. Some ATA’s also have an FXO port for connectivity to the PSTN. ATA’s also convert digital packets back into analog voice streams.
So an ATA is a device that sits between your router or modem and your home phone, that takes your speech and converts it into digital packets to be sent over the internet by your VoIP service provider, and vice versa.
What is an FXS Port?
FXS stands for Foreign Exchange Station. An FXS port is an interface on that connects station devices such as phones or a PBX to the ATA. An FXS port would be where you plug your home phone into an ATA. The number of FXS ports dictates the number of phones that can be plugged into an ATA.
What is an FXO Port?
FXO stands for Foreign Exchange Office. An FXO port is an interface that receives your home land-line telephone service connection. An FXO port would be where you plug your home telephone line into an ATA. An FXO port allows you to use both VoIP calling and traditional PSTN calling. This is often referred to as a “life-line”.
What is an RJ45 Port?
An RJ45 port is an interface that connects your ATA to your home data network. An RJ45 is where you would plug your CAT5 cabling coming from your modem or router in order to give the ATA access to the Internet. The number of RJ45 ports on an ATA is important as you may need a certain ATA if you do or do not have a home router.
Which ATA is Right For Me?
Here is How Your Select the Right ATA For Your Situation:
- How Many Home Phones Do You Need to Connect? – The number of home phones that you would like to connect to your ATA will dictate the number of FXS ports. If you want to connect one home phone, you will need an ATA with one FXS port. If you want to connect two home phones, you will need an ATA with two FXS ports. Most service providers only offer ATA’s with 2 FXS ports, so if you are planning on connecting more than two home phones, you will need to get more than one ATA. Contact your VoIP service provider for more information on how to connect more than one ATA device to their service.
- Are You Going to Keep Your PSTN Phone Line? – If you plan on keeping your PSTN line, as a life-line in case your network connection goes down, then you will need an ATA with an FXO port. Now, if you decide that you want this functionality, first make sure that your VoIP service provider supports this type of functionality as some do not. Most ATA’s only come with one FXO port, so you will only be able to connect your ATA to one PSTn phone line.
- Do You Have A Home Router? – The existence of a home router will be a big factor in the number of RJ45 ports you will need your ATA to have. The reason? If you do not have a router for your home, that means your computer is connected directly to your cable/dsl modem. Without a router, only your ATA or computer to could be connected to the Internet at any given time. That sucks. If you do not have a home router, your home router has no more open ports, or your phone is near your computer, you want an ATA with 2 RJ45 ports, so that you connect your ATA and your computer to the Internet.