Softphones, also called VoIP clients or video conferencing clients, provide voice and video calling over the Internet. Here are my observations on those that I’ve come across.
When evaluating softphones, features I look for include:
- Use a standard telephony protocol so you are free to choose your preferred service provider, and you can call people who use different softphones
- Voice, video, and text messaging
- Have a large, helpful user community
- Open source and be available in the package managers of major distributions
- Encryption available, preferably in a form that does not require the other party to use the same softphone as you do
Blink: Qt; multiplatform. Encryption. Open source. Several features, such as chat sessions, are only available on the Mac client.
Ekiga: Multiprotocol (SIP and H.323) and multiplatform. No text message logging. The most popular open source softphone.
QuteCom: Qt; multiplatform. Unified IM and softphone (SIP) client. Open source. Video is only available when both parties are using QuteCom. No documentation or support. I was unable to log on with known good SIP accounts even with the local firewall disabled, and gave up.
SIP Communicator: Java. Multiprotocol and multiplatform. Unified IM and softphone (SIP) client. Encryption. Open source. Alpha, but some users find it stable for their needs. I was unable to log on with known good SIP accounts even with the local firewall disabled, got no response on the IRC channel, and gave up.
Skype: QT. Proprietary softphone limited to its own proprietary protocol. Claims to be encrypted, but without the source code, who can say? Many plugins. Desktop sharing. It’s given me nothing but trouble, but some Linux users report good results.
TeamSpeak: Proprietary softphone that uses its own proprietary protocol. The server software is freely available; you would first set up a server, then you and other users would set up your clients and connect to your server. It’s the most reliable and best sounding VoIP solution I have tried.
Aside from the software you will also need a SIP account. Some softphones offer to sign you up for a SIP account as part of a first time setup wizard, or you can select your own provider. I am testing ekiga.net and iptel.org.