There's not a gateway vendor that's not intently focusing on gatekeeper development. According to Jackson, vendor interoperability remains a major concern. The fact of the matter is that gateways or technologies from one vendor do not necessarily work with technology from another. That means that as a service provider, you can only use technology from a single vendor. Clearly, standards have to mature a little farther so that we have interoperability.
Several vendors agree that interoperability remains a hurdle and have united to deal with the issue.
Some of OSP's benefits include secure, mutual authentication of communicating parties through public and private key cryptography methods, and nonrepudiation of all communications through digital signature technology. Cisco is working with VocalTec to develop a high degree of interoperability between their respective IP telephony systems. According to Cisco, during the first phase of the project, the vendors will interoperate the intelligence of the carrier-grade VocalTec Gatekeeper with Cisco gateways. The second phase of the project will focus on interoperability between the two companies' complete product sets, including gateways, gatekeepers, conferencing servers and clients. The companies demonstrated this interoperability at last fall's Voice on the Net conference in Washington D.C., and agreed to publish the findings of their H.323-based interoperability.