Open SER
= project to develop an open SIP Express Router
URL = http://www.openser.org/
Description
"Robust Open Source (GPL) SIP (RFC3261) server implementation. Among features: VoIP SIP registrar/proxy/router/application server, TLS secure communication, AAA, ENUM, LCR, load balancing, NAT traversal, OSP, CPL, SNMP, IM&Presence, DNS failover." (http://sourceforge.net/projects/openser/)
Technical Motivation
"Why am I even bothering with OpenSER when there's Asterisk? Asterisk is great, but it's not really a SIP proxy and it doesn't scale as well as OpenSER. A single OpenSER box can handle more registrations and call setups, than a large cluster of Asterisk boxes can at this time. This is why Free World Dialup uses SER as it's SIP proxy and not Asterisk." (http://www.oldskoolphreak.com/tfiles/voip/beginners_openser.txt)
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