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What is VoIP ?

VoIP allows you to make calls using an IP network, over a data network like the Internet. VoIP converts the voice signal from your telephone into a digital signal that travels over the internet then converts it back at the other end so you can speak to anyone with a regular phone number. When placing a VoIP call using a phone with an adapter, you'll hear a dial tone and dial just as you always have. VoIP may also allow you to make a call directly from a computer using a conventional telephone or a microphone.

What Kind of VoIP Equipment Do I Need?

A broadband (high speed Internet) connection is required. This can be through a cable modem, or high speed services such as DSL or a local area network. You can hook up an inexpensive microphone to your computer and send your voice through a cable modem or connect a phone directly to a telephone adaptor.

Asterisk Hardware

Asterisk is an open source IP PABX that runs on the Linux operating system. It is an extremely powerful product capable of the most advanced PABX functions including voice-mail, conference calls, trunking, hunt groups, and much more. Being IP based, users connecting to Asterisk can be geographically distributed, yet still connected to the same business grade PABX. In order to connect telephones directly to an Asterisk box, or to connect Asterisk to the PSTN, interconnect cards are required.

VoIP Phone

VoIP phone looks and feels like standard desk-phones, but connect to the Internet (either via an Ethernet connection or WiFi) rather than the phone line socket in wall. They are independent from your computer, meaning you do not have to have your computer on to make and receive calls.
A wide range of IP phones are available from the ultra-basic phones, to advanced phones with multi-line support, high quality speaker-phone, power over Ethernet, and more!

VoIP gateway ATA

VoIP gateway ATA allows you to use any standard analogue telephone as an IP phone. Simply plug your telephone (cordless phone if you like) into the RJ-11 port on the ATA, connect your ATA to the Internet by plugging it into a spare Ethernet socket on your router, and your old telephone is transformed into an Internet telephone. Once set up, they are independent from your computer, meaning you do not have to have your computer on to make and receive calls.
Many analogue telephone adapters also have a built in router, providing some advantages over the standard ATAs. These are lited in the router category.

How Can I Place a VoIP Call?

Depending on the service, one way to place a VoIP call is to pick up your phone and dial the number, using an adaptor that connects to your existing high-speed Internet connection. The call goes through your local telephone company to a VoIP provider. The phone call goes over the Internet to the called party's local telephone company for the completion of the call. Another way is to utilize a microphone headset plugged into your computer. The number is placed using the keyboard and is routed through your cable modem.

If I have Internet Voice service, who can I call?

Depending upon your service, you might be limited only to other subscribers to the service, or you may be able to call any phone number, anywhere in the world. The call can be made to a local number, a mobile phone, to a long distance number, or an international number. You may even utilize the service to speak with more than one person at a time. The person you are calling does not need any special equipment, just a phone.

What Are Some Advantages of VoIP?

Because Internet Voice is digital, it may offer features and services that are not available with a traditional phone. If you have a broadband internet connection, you need not maintain and pay the additional cost for a line just to make telephone calls.
With many Internet Voice plans you can talk for as long as you want with any person in the world (the requirement is that the other person has an Internet connection). You can also talk with many people at the same time without any additional cost.

What Are Some disadvantages of VoIP?

If you're considering replacing your traditional telephone service with Internet Voice, there are some possible differences:
Some Internet Voice services don't work during power outages and the service provider may not offer backup power;
It may be difficult for some Internet Voice services to seamlessly connect with the 911 dispatch center or identify the location of Internet Voice 911 callers; or
They may or may not offer white page listings.

Does my Computer Have to be Turned on?

Not if you are making calls with a phone and adaptor or special VoIP phone , but your broadband Internet connection needs to be active. You can also use your computer while talking on the phone.

Can I Take My Phone Adapter with me When I Travel?

You may be able to use your VoIP service wherever you travel as long as you have a high speed Internet connection available. In that case it would work the same as from your home or business.

What hardware is required For VoIP?

Here you will find a brief overview of various options for your VoIP service.

For more information only the actual products please check our VoIP Hardware Catalog for a detailed description of the most common VoIP hardware.

How Do I Know If I have a VoIP phone Call?

It will ring like any other call.

ADSL Modem/Routers with VoIP

"All-in-one" combo units are becoming very popular amongst home and small business users. They combine an ADSL modem (some are ADSL2 and ADSL2+ compatible), router, and built in voice over IP telephone adapter in the one unit. Some units also have multi-port Ethernet switches, 802.11g wirless access points, and advanced firewall and VPN functions. A single unit covering multiple needs means less hardware collecting dust, and fewer used power points! Additionally, a combination unit ensures that you will not have any NAT or firewall issues as the router inherently 'knows' about the VoIP traffic. These units automatically prioritise traffic to ensure call quality is never compromised by other Internet activity.
Plain routers (without the ADSL modem component) are also available.

PC Headsets

These headsets can be used with any voice over IP application on your computer. In fact, they can be used for any application that requires a microphone and/or speakers! We have sourced only the most comfortable headsets that are suitable for use with Internet telephony. Some of our headsets plug into a spare USB port and act as a separate audio device for your computer, whilst others simply plug into your sound card, allowing them to be used on any operating system without requiring drivers to be installed. We have a selection of both stereo and mono headsets (which some people find more natural for telephone conversations).

PC Handsets, Speakerphones & Telephone Adapters

'Telephone-like' handsets connect to your computer via the sound card or a USB port and work together with a softphone to provide you with a complete VoIP experience. We also have USB based hands-free speaker-phones, and telephone adapters which are similar to ATAs, but connect to your computer rather than your router.
All of these devices either work without any special software or come with free software. Many work on MacOS and Linux systems as well as Windows.

Business Grade Media Gateways
Media gateways are suitable for businesses requiring a number of voice over IP lines - either as an independent option or hooked up to an existing PABX. These gateways do the job of multiple ATAs in the one unit as well as additional routing functions.
The Octtel series of gateways have a built in phonebook manager allowing you to manage a group of devices without any external SIP server. This phonebook feature can also be used in conjunction with a SIP proxy if desired.

Gateways with FXO ports are not yet A-ticked and may only be used for internal testing purposes.
Routers with VoIP

These products are 'all-in-one' devices that combine a router and a voice over IP adapter in one. By using a single device for your router and VoIP hardware, not only do you have one less piece of hardware to deal with (and one less powerpoint that is occupied), you are guaranteed that you will not have any NAT or firewall issues as the router inherently 'knows' about the VoIP traffic. Additionally, these units automatically prioritise traffic to ensure call quality is never compromised by other Internet activity.
Routers with built in ADSL modems are also available.

Is there a difference between making a Local Call and a Long Distance Call?

Some VoIP providers offer their services for free, normally only for calls to other subscribers to the service. Your VoIP provider may permit you to select an area code different from the area in which you live. This means you may not incur long distance charges if you call a number in your area code regardless of geography. It also means that people who call you may incur long distance charges depending on their area code and service.
Some VoIP providers charge for a long distance call to a number outside your calling area, similar to existing, traditional wireline telephone service. Other VoIP providers permit you to call anywhere at a flat rate for a fixed number of minutes.

See also

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-Global System for Mobile Communications
-About VoIP
-SIP:Session Initiation Protocol
-List of commercial voice over IP network providers
-Mobile VoIP
-List of SIP software
-VoIP links
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