This VoIP faq (frequently asked questions) page has been created to provide you a quick reference to most requested topics. If you don't find what you looked for, scroll down to comment box and submit your request. I or regular visitors and contributors, will do our best to answer it as soon as we can.

1. General VoIP FAQ

1.1 What is an IP Telephony?    

1.2 What is VoIP?                          

1.3 What are VoIP Basics?

1.1 What is IP Telephony?

IP Telephony is a communication technology used for making voice calls via the Internet protocol (IP) networks. Users don’t have to rely on the traditional public switched telephone network (PSTN) to benefit from IP Telephony. It is becoming more and more common these days due to its cost effectiveness.

1.2 What is VoIP?

VoIP is a technology which enables users to make voice calls over the Internet Protocol (IP) networks and falls under the umbrella of IP Telephony. The term VOIP (Voice over Internet Protocol) is often interchangeably used with IP telephony. Check VoIP definition link to read other VoIP terminologies.

1.3 What are VoIP Basics?

In the early days, VoIP was only available through computer based soft-phone applications. Hence, the system was called PC to PC and PC to Phone calls. I mention the main basics of VoIP services and systems on VoIP Telephony Basics page.

1.4 How does VoIP work?

VoIP uses your Internet connection, with the help of VoIP hard phones or devices transmit your data, video and voice communications via the Internet (packet switched network). With traditional phone service the calls are transmitted through public switched telephone network (PSTN) NOT Internet.  On how VoIP works link you will find more details and diagrams about how the technology works.

1.5 Is there a difference between IP Telephony and VoIP?

Technically speaking, yes, visit VoIP vs IP Telephony page which explain that briefly.

2. Hardware VoIP FAQ

2.1 What is a Hard-phone?

A Hard-phone is a device from any of the VoIP devices family.  Hard phones support transmission control protocol/Internet protocol (TCP/IP) which is essential for VoIP to work. They usually have at least one RJ-45 connector port (also known as Ethernet port) and RJ-11 for plugging telephone devices (except IP phones). See the following hardware.

2.2  What is USB Phone?

USB phones come with a USB connector to plug on your computer or laptop. That helps you avoid a headset/headpone and microphone. USB phones can be used with different softphones and services such as Skype, NetMeeting, Net2Phone and many others. See VoIP USB phone article.

2.3  What is an ATA?

An ATA stands for Analog Telephone Adapter which is used to convert or switch our voice calls.  Most ATA devices are compatible with majority VoIP service providers as they support the most popular protocols H.323 and SIP. Visit VoIP phone adapter for more details.

2.4 What is VoIP phone (IP Phone)?

A VoIP phone also known an IP phone is a device which usually comes with built-in NIC (Network Interface Cards) for connecting your Ethernet cable to it. IP phone utilizes VoIP technologies to communicate voice calls just like the traditional PSTN phones but instead they use Internet. These phones use different protocols such as Skinny Client Control Protocol (SCCP), Session Initiation Protocol (SIP) or different proprietary protocols which are seen in certain software such as Skype. VoIP phones and can also be used with IP PBX. Check IP phone link for more info.

2.5 What is VoIP Gateway?

A terminal device that is usually used by small business and VoIP service resellers such as callshop and Internet café owners. A VoIP gateway comes with multiple FXS and FXO ports. Gateways have the ability to be connected with PSTN as well as IP networks. They can also be configured to be used in different ways. More details on VoIP Gateway article.

2.6 What is VoIP router?

VoIP router is a device that comes with multiple RJ-45 ports for connecting your electronic equipments that need network access such as PC, All-in-one printer etc. It comes with FXS port for your standard analogue telephone so it gives you flexibility while acting as an ATA and router (LAN). Refer to VoIP router page.

2.7  What is an IP-PBX hardware?

IP-PBX stands for ‘Internet Protocol’ – ‘ Private Branch eXchange. When IP-PBX comes as hardware, it provides more features and benefits than traditional PBX that can only work with PSTN lines. IP-PBX enables you switch over your lines (usually used with in the businesses) from PSTN to VoIP network or from VoIP network to PSTN.  Go to IP-PBX link for further reading.

2.8 What is a Switch?

A Soft-Switch may come as a hardware or software. In the case of hardware it is mostly used by VoIP providers / wholesale ITSPs for originating and terminating voice traffic minutes.

2.9 What is Wireless / Wi-Fi Phone?

Wireless / Wi-Fi Phones look like USB phone and cellular/mobile, part of the VoIP device accessories used over wireless Internet access.  See Wireless VoIP Phones article.

2.10  What is SIP device?

SIP device is a VoIP device that supports SIP protocol. See SIP software below.

2.11  What is H.323 device?

A VoIP device that works with H.323 protocol.

3. Software VoIP FAQ

3.1 What is VoIP Software?

There are different kind of VoIP Software which are developed to meet certain needs and requirements. Some of them are freeware while others are paid. Visit VoIP Software page.

3.2 What is Softphone?

A Softphone is an application that enables you to make and receive calls from your computer (PC), laptop, Smart phones, PC Tablets and PDAs along with other extra features. One of the popular such softphone is Skype. Check VoIP soft-phone link for more details.

3.3 What is an IP-PBX software?

An IP-PBX software is an application which allows you to make voice calls without using any IP-PBX hardware. Mostly such software are based on SIP protocol.

3.4 What is Soft-Switch?

A soft-switch is a software application mostly used by VoIP providers to track, record, control VoIP traffics/minutes and bill their clients. Take a look at soft-switch image here.

3.5 What is SIP?

SIP which stands for Session Initiation Protocol, is a standard signalling protocol for IP telephony. SIP is defined by IETF (Internet Engineering Task Force).

3.6 What is H.323?

Similar to SIP, H.323 is also a protocol which has the similar function of carrying VoIP traffic and transferring different communications over the H.323 networks and is used more than the SIP.

4. Service and Solution VoIP FAQ

4.1 What’s click to call?

Click to call is a communication method similar to call-back solution which is based on web browsers. A person has to click on an object such as hyperlink text, email links or attachments and buttons. It is also referred to as click-to-chat, click-to-text and click-to-talk. For more details go to click to call article.

4.2 What is PC to PC / PC to Phone calls?

A simple way of communicating with other people over the Internet with the help of software also known as softphone. It lets you make calls from your PC to another users’ PC or phone. Refer to Pc to PC and PC to phone call links for more details.

4.3 What is Phone to PC Call?

Phone to PC Call is a communication method in which users make calls from their phones to someone on his/her computer or laptop. The receiver’s computer has a soft-phone application with a VoIP telephone number for this purpose.

4.4 What is device to phone call?

Device to phone call is a form of communication which you make a phone call using a VoIP device. Most commonly used devices are USB phones, ATAs, VoIP phones etc... Visit VoIP devices page (from left navigation links) for more info. 

4.5 What is phone to device call?

Phone to device call is similar to Phone to PC Call (mentioned above) in this case the receiver would be using a VoIP device instead a computer.

4.6 What is phone to phone call?

Phone to phone call is normally considered the traditional way of communicating over the PSTN based phones. However, VoIP developers recently provided a solution that users can access to through their regular phone without depending on Internet. For instance, call back and calling card systems don’t require a computer or Internet.

4.7 What is Residential VoIP?

Residential VoIP is an Internet telephone service which is specifically designed for end users / consumers.  Check residential VoIP services link where you will find more details.

4.8 What is Business VoIP?

Business VoIP is an Internet telephone service offered by VoIP service providers companies specifically for businesses. Please visit VoIP for Business article for more information.

4.9 What is International VoIP?

A VoIP solution that allows cheap international calls along with some other extra features depending upon your package.

4.10  What is VoIP call center?

VoIP call center is a service which has become quite popular among the commercial users because of its ability to send and receive large amount of telephone calls. It is mostly used to provide customer support (usually inbound call centers) and do telemarketing (usually outbound call centers) by large companies as well as small BPOs (Business process outsourcing, in this context it means offshore call centers in countries like Philippines, India, Pakistan and Bangladesh). Check out VoIP Call Center link.

4.11  What is web conferencing?

Web conference is when one or more users conduct Internet based real-time face-to-face conference. Refer to web conferencing article.

4.12 What is DID / Virtual Number?

DID which stands for Direct Inward Dialling is a number allotted to you by a VoIP company or DID provider, which you purchase and can access from anywhere in the world where Internet is available. DID is also known as Virtual Number in some cases.  Go to DID – Virtual Number page.

4.13 What is FoIP?

FoIP is an abbreviation for Fax over IP, sometimes called online fax and eFax etc. FoIP technology lets you send and receive faxes over the Internet. See FoIP page.

4.14 What is SIP Trunking?

SIP Trunking is a solution provided by VoIP providers to mainly enterprises. SIP trunking helps you to replace your BRI/PRI lines, PSTN gateways as well. See SIP trunking.

4.15 What is UC?

UC stands for Unified Communications, a methodology by which multiple real-time communicational methods are merged or integrated together. Basically you collaborate and unify all types of communications such as: telephony, IP telephony, instant messaging, speech recognition, video conferencing, call control, fax, voicemail, e-mail and SMS into one platform system.

5. Service Providers VoIP FAQ

5.1 What is VoIP provider?

VoIP providers also known as Internet Phone Company provides VoIP services, solutions and systems to residential and commercial customers. Just like the ISP provides you Internet access and traditional phone company provides fixed/landline telephone lines. VoIP subscribers require a VoIP provider. Visit VoIP phone service provider for more info.

5.2 What is a VoIP Carrier?

Usually carriers are ILECs/CLECs e.g. AT&T and Verizon and others. A VoIP Carrier is the main backbone of VoIP services and solutions. They lease telephone lines to ITSPs and VoIP providers. Some list of top corporations in N.America can be found on VoIP carriers page.

5.3 What's an ITSP?

ITSP stands for Internet telephony service provider, a company that provides VoIP based telecommunications services. This term is mostly used among B2B VoIP companies meaning VoIP wholesale providers.

Carrier-ITSP-VoIP-Provider Diagram

Hope you enjoyed the above VoIP FAQ and found them helpful. Now it’s your turn to suggest and make additions. As I said at the beginning of this page you’re always welcome to comment below.

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VoIP Basics

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What's a Broadband VoIP Phone?

What's Wi-Max?

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