SIP also makes it possible to integrate presence applications from different vendors, as well as use phones from one with the IP PBX of another. Many vendors have resisted this--after all, half their revenue comes from phones.
For our review (see "Live in the Labs: IP PBXs," ), we required that vendors spec out third-party phones and be prepared to demonstrate interoperability with three different vendors' endpoints. We tested some advanced features, and though the results weren't perfect, we believe SIP is a viable protocol for multivendor, enterprise IP-PBX phones. Despite some interoperability problems, we were impressed that Vonexus requires third-party SIP phones and Zultys uses only SIP phones. We were also pleased that Avaya has an extensive certification process for third-party SIP support and has demonstrated a commitment to making it work.
This is another advantage that Avaya has over its rival Cisco. Although Cisco has support for SIP trunking in its CallManager product, you can't buy SIP-based phones from a third party that will work with Cisco's CallManager. We hope that changes. Even though Avaya has a third-party certification program, it does not sell third-party phones, although we hope that will also change in the future. No matter how you cut it, we recommend making third-party SIP support a requirement.
Don't recklessly crash the VoIP party, however--as with any technology decision, you shouldn't make a move just because you think everyone is doing it (they aren't) or because of vague ROI claims. Yes, VoIP has matured significantly and deserves serious consideration, whether as a PBX replacement, for trunks between office locations or to enable new presence-based services. But if your old PBX is humming along and supporting the communications needs of your business, maybe VoIP isn't justified. In our reader poll, 11 percent of respondents said they have no plans for production-level VoIP because their current PBXs work just fine.
Subsea cable alternatives can provide a level of comfort for those concerned about disruptions. Realistically, they will continue to play a small, but critical role in the short term.
Maintaining existing network infrastructures often incurs huge technical debt before newer technologies are adopted over time.
Amid ongoing regional uncertainties, telecom infrastructure in the Middle East has expand to include terrestrial low-latency network infrastructure, which offers resilience and agility in navigating political complexities without relying solely on undersea networks.
