[posted on elastix.org] Some of you may want be wanting to increase the capacity of your Elastix machine. Asterisk generally has issues when you start to put a lot of SIP peers on it. One of the best ways to get around this is to install a proper SIP server and join it with asterisk. This allows you to register all your SIP handsets to the SIP server and make calls through to your asterisk machine.

The Kamailio module for Elastix allows you to easily integrate Elastix with a enterprise SIP server. All SIP handsets register to Kamailio. All internal SIP calls stay within Kamailio however if a call is external then Kamailio will push the call out to asterisk to deal with it.

VOIP Today magazine (www.voiptoday.org) is privileged to conduct exclusive interview with Kamailio (OpenSER) co-founder and core developer of OpenSER and SER projects Daniel-Constantin Mierla.

Kamailio (former OpenSER) is an Open Source SIP Server released under GPL, able to handle thousands of call setups per second. Among features: asynchronous TCP, UDP and SCTP, secure communication via TLS for VoIP (voice, video), SIMPLE instant messaging and presence, ENUM, least cost routing, load balancing, routing fail-over, accounting, authentication and authorization against MySQL, Postgres, Oracle, Radius, LDAP, XMLRPC control interface, SNMP monitoring. It can be used to build large VoIP servicing platforms or to scale up SIP-to-PSTN gateways, PBX systems or media servers like Asterisk™, FreeSWITCH™ or SEMS.

VOIP Today magazine spoke with Daniel-Constantin Mierla about Business , technology and products .