PHP SIP Telephony Library (Integrated/Evaluated)

Overview

A copy of the open-source PhpSIP library (php-sip, originally hosted on Google Code) used to send and receive SIP messages directly from PHP. Integrated and evaluated as the VoIP/telephony layer behind the callinfo communications backend, not authored here.

Why It Exists

The communications builds needed to speak SIP, the signalling protocol behind VoIP calls, from PHP. PhpSIP provided a ready-made client for crafting SIP requests (INVITE, REGISTER, etc.) without dropping to a C SIP stack.

What We Built

Integration and evaluation of the PhpSIP library: the core PhpSIP.class.php, its PhpSIP.Exception error types and an example.php usage script, wired into the telephony stack. The README simply points to the upstream php-sip project documentation. A conflicted-copy artifact in the folder shows it was actively worked with across machines.

Technologies & Approach

PhpSIP communicates over UDP sockets to build and parse SIP messages in pure PHP, chosen so VoIP call signalling could be driven from the same PHP services as the rest of the communications backend.

Outcome / Impact

Provided the SIP/VoIP signalling capability used by the callinfo project, demonstrating the ability to evaluate and fold a specialised low-level protocol library into a larger telephony system.

Capabilities Demonstrated

• Working with SIP/VoIP signalling from PHP
• Evaluating and integrating third-party protocol libraries
• Driving call signalling within a broader communications backend