Voice-over-IP (VoIP) networking comprises many components and network managers might find themselves treading on new and fragile ground as they investigate VoIP projects.  This white paper provides an inexpensive path that you can use to learn more about a particular VOIP technology, Session Initiation Protocol (SIP), get experience with the products and the market, and become more confident before building an enterprise-wide deployment.  The products and services mentioned in this white paper are representative based on our team's recommendations; others are available.

Start by using someone else's SIP server

You'll need a phone.  To start, get a free or demo version of a software-based phone for your desktop (Windows or Mac are common, but Linux soft phones exist as well).  X-Lite from Xten is a free, multi-platform soft phone with many features.  When using a soft phone you may also want to invest in an inexpensive headset if you don't have one already.

The two biggest components of a SIP network are the phones and the SIP proxy servers.  Start by getting a phone of your own and using someone else's SIP proxy server.  You can learn more about what kinds of phones are used in SIP and what a SIP proxy server is by reading our white paper "What is SIP?"  A number of free SIP-based telephony projects are alive and well on the Internet that will provide the SIP proxy server for you to test with.  You can start by getting a phone and hooking it up to someone else's SIP network.  That will help you to learn SIP terms and concepts, and give you an easy way to learn debugging.

Begin by signing up for a Free World Dialup (FWD) account.  FWD is, as the name suggests, free, and provides an Internet-wide SIP network with some limited Public Switched Telephone Network (PSTN) gateway capabilities.  You can hook multiple phones of your own up to FWD (and talk to each other using FWD) as well as other people who are connected to FWD.  Because FWD requires SIP technology, you'll mostly find other small businesses and technologists connected.  Nevertheless, you'll still want to be aware of the security issues involved---a good way to start is by leaving your test phone outside of your company firewall.  Make sure you read and follow the "Get FWD" Quick Start Guide.