• Agora Labs (former elemedia stacks) http://www.agoralabs.com
• Continuous Computing Corporation Trillium SIP stack http://www.ccpu.com
• Data Connection http://www.dataconnection.com
• Encore Software Ltd. http://www.ncoretech.com
• EyeP Media http://www.eyepmedia.com/
• Flextronics Software Systems (formerly: Hughes Software Systems) http://www.hssworld.com
• HCL Technologies Ltd http://www.hcltech.com/voip
• HelloSoft http://www.hellosoft.com/
• Indigo Software http://www.indigosw.com/
• M5T http://www.m5t.com Advanced SIP Toolkits with security (TLS, SRTP, MIKEY) and NAT traversal (STUN, ICE)
• Mistral http://www.mistralsoftware.com/
• Netbricks http://www.netbricks.com
• Ortena Networks http://www.ortena.com/product1.htm
• PJSIP
• Radvision http://www.radvision.com/DeveloperSolutions/ProtocolToolkitsAndPlatforms Protocol toolkits for SIP, 3G-324m, MGCP, and more
• SIPquest http://www.sipquest.com/
• Surf Communication Solutions http://www.surf-com.com enabling technologies for media processing on TI DSPs
• SX Design http://www.sxdesign.com/products/
• TeleSoft International http://www.nine-9s.com/prod_embedded_sip_protocol_stack.htm
• TNT Systems http://www.tntss.com/products.htm
• Unicoi Systems http://www.unicoi.com/
• Uniqall http://www.uniqall.com/
• Vovida http://www.vovida.org/
• Parrish Systems Inc. (An Embedded SIP Stack coded in ANSI 'C') http://www.parrishsys.com/
• MBDSYS (Open Source Voice and Video over IP toolkit) http://www.mbdsys.com/opensource/verona/

• DiamondWare
• Octiv

See Also