Introduction

VOIP is an acronym for Voice Over Internet Protocol, or in more common terms phone service over the Internet.
If you have a reasonable quality Internet connection you can get phone service delivered through your Internet connection instead of from your local phone company.

Some people use VOIP in addition to their traditional phone service, since VOIP service providers usually offer lower rates than traditional phone companies, but sometimes doesn't offer 911 service, phone directory listings, 411 service, or other common phone services. While many VoIP providers offer these services, consistent industry-wide means of offering these are still developing.

How does VOIP work?

A way is required to turn analog phone signals into digital signals that can be sent over the Internet.
This function can either be included into the phone itself (See: VOIP Phones) or in a separate box like an ATA .

VOIP Using an ATA

Ordinary Phone ---- ATA ---- Ethernet ---- Router ---- Internet ---- VOIP Service Provider

VOIP using an IP Phone

IP Phone ----- Ethernet ----- Router ---- Internet ---- VOIP Service Provider

VOIP connecting directly

It is also possible to bypass a VOIP Service Provider and directly connect to another VOIP user. However, if the VOIP devices are behind NAT routers, there may be problems with this approach.

IP Phone ----- Ethernet ----- Router ---- Internet ---- Router ---- Ethernet ---- IP Phone

Applications using VOIP

Traditional telephony applications, such as outbound call center applications and inbound IVR applications, normally can be run on VOIP.

Why use VOIP?

There are two major reasons to use VOIP

• Lower Cost
• Increased functionality

Lower Cost

In general phone service via VOIP costs less than equivalent service from traditional sources. This is largely a function of traditional phone services either being monopolies or government entities. There are also some cost savings due to using a single network to carry voice and data. This is especially true when users have existing under-utilized network capacity that they can use for VOIP without any additional costs.

In the most extreme case, users see VOIP phone calls (even international) as FREE. While there is a cost for their Internet service, using VOIP over this service may not involve any extra charges, so the users view the calls as free. There are a number of services that have sprung up to facilitate this type of "free" VOIP call. Examples are: Free World Dialup and Skype for a more complete list see: VOIP Service Providers

Increased Functionality

VOIP makes easy some things that are difficult to impossible with traditional phone networks.

• Incoming phone calls are automatically routed to your VOIP phone where ever you plug it into the network. Take your VOIP phone with you on a trip, and anywhere you connect it to the Internet, you can receive your incoming calls.
• Call center agents using VOIP phones can easily work from anywhere with a good Internet connection.

See also

• VoIP Review - Read customer reviews for various VoIP service providers
• VoIP Mechanic - Tutorials and guides on setting up and installing VoIP
• Do we really need VoIP?- Why should you switch to VoIP services (benefits, proc's & con's)
• VOIP Benefits for business- VOIP Information resource for business.
• A White Paper with explanations that contrast how PSTN and VOIP work.
• DIY VoIP Guide:Easy Step-by-Step Guide - How to Make Free Internet Phone Call with VoIP Technology
• What is VoIP and what it can do for you
• How to use VoIP:6 ways to use VoIP
• "How to Start an ITSP" If you considering to start an ITSP then this paper is a must-read. It draws from years of experience from the author in setting up ITSPs around the world.
• Implementing VoIP Services Into a Business The implementation of VoIP services
• PSTN vs VoIP - A number of facts comparison between PSTN (old style telephony networks) and VoIP
• Setup IPPBX for small business step by step: How to establish a small VOIP network.
• Voip Dutch Voip information portal.
• VOIP Books recommended by Voip-info.org
• What is VoIP:- Internet Voice Explained.
• VoIP FAQ - Questions about VoIP and Softswitch solutions
• Where to start? - How to start with VoIP telephony
• "How to Become an ITSP" - Learn how to start your own VoIP business.
• How to Sell Wholesale VoIP - Part 1: Choosing your Target Market
• How to Sell Wholesale VoIP - Part 2: Choosing what VoIP Services to Sell
• Selecting a Wholesale DID Origination Provider - Part 1: Footprint and Features
• Selecting a Wholesale DID Origination Provider - Part 2: Monthly Recurring Cost and Non-Recurring Costs
• Selecting a DID Origination Provider - Part 3: Support, Number Porting, and Billing
• What is SIP
• VoIP Service Providers
• VoIP Termination
• VoIP Origination

Books

If you use one of the Amazon links below to purchase a book voip-info.org will benefit.
This list is loosely in order starting with non-technical overviews, and moving on to comprehensive technical references.

VOIP for Dummies, by Timothy V. Kelly

• A non-technical introduction to VOIP
• Amazon

Switching to VOIP, by Ted Wallingford

• An introduction that assumes some basic knowledge of computer networking
• Amazon

Newton's Telecom Dictionary, 26th Edition, By Harry Netwon

• Covers Telecommunications, Networking, Information Technologies, and The Internet
• A long time telecom industry standard.
• Amazon

Webster's New World Telecom Dictionary, by Ray Horak

• A new Telecom dictionary with very good reviews. By the same author as Telecommunications and Data Communications Handbook
• Amazon

Telecommunications and Data Communications Handbook, by Ray Horak

• A well respected reference handbook with lots of technical detail.
• Amazon

If you would like to recommend a VOIP book, please visit VOIP Books