Links to related resources

Some free telephony projects:

• FreeSwitch (uses SpanDSP)
• BareSIP (uses SpanDSP)
• Bayonne
• OpenSIPS (was OpenSER)
• Kamailio (was OpenSER)
• SIP Foundry
• Asterisk (optionally uses SpanDSP)

Some makers of dumb (or nearly dumb) telephony hardware:

• Atcom
• OpenVox
• Sangoma
• Xorcom
• Digium
• Pika Technologies
• Redfone Communications