Testing of incorrect SIP messages processing

This article deals with the issue of testing a correct implementation of SIP signaling at different endpoints. Our testing was based on the basic standard of RFC 3261. We focused on proceeding an INVITE request with regard to its correct syntax. In the CipherCAD environment, we designed a model for an automatic testing via differently modified INVITE requests. We carried out a series of tests which proved very different behaviour of individual endpoints. The standard requirements were often not fulfilled.