Is SIP interoperability still a major concern?
As Nemertes Research analyst Irwin Lazar puts it, “it’s more a hindrance than major flaw at this point. Three years ago, a team of iLab engineers found that while different VoIP vendors could ensure basic connectivity between their SIP-based phones and devices, there were also “significant failure rates” for enterprise VoIP features and standard security parameters. Lazar says that today key basic VoIP features such as caller ID, message waiting lights, hold and three-way calling are “pretty well standardized,” but that more advanced features such as multiple line appearances, call bridging and intercom still face significant SIP interoperability issues between vendors. Jeff Brandt, the general manager of IT infrastructure design and engineering for business processing firm Sutherland Global Services, expresses a similar viewpoint and says that he has concerns about a lack of SIP interoperability for advanced carrier-level features for his company’s call centers, noting in particular t
