libpjsip-simple2 2.1.0.0.ast20130823-1 (i386 binary) in ubuntu xenial

 PJSIP (a.k.a PJProject) is a multimedia communication library written
 in C language implementing standard based protocols such as SIP, SDP,
 RTP, STUN, TURN, and ICE. It combines signaling protocol (SIP) with rich
 multimedia framework and NAT traversal functionality into high level API
 that is portable and suitable for almost any type of systems ranging
 from desktops, embedded systems, to mobile handsets.
 .
 This package includes a SIP SIMPLE Instant Messaging library.