IP Telephony Interoperability Remains Topical

Written by Paula
July 31, 1999

Posted: 08/1999

IP Telephony Interoperability Remains Topical
By Paula Bernier

In general, Internet protocol (IP) telephony and, specifically, interoperability, were
hot topics at SUPERCOMM ’99 in Atlanta.

Of course, as with all new technologies, interoperability among different vendors’
products is always an issue, and IP telephony is no exception.

Although the 3 1/2-year-old industry quickly adopted the H.323 standard borrowed from
the videoconferencing world, different implementations of the standard exist. And H.323
only addresses certain aspects of interoperability and communications. Now vendors are
getting together on a one-to-one basis for interoperability.

Meanwhile, a broad slate of equipment providers in the past few months have lined up
behind an implementation of H.323 version 2 called iNow! and the list continues to grow.
Excel Switching Corp., Hyannis, Mass., and Nokia Inc., Helsinki, Finland, for example,
have thrown their support behind the iNow! initiative.

While many vendors have put the H.323 label on their products, many equipment providers
believe that H.323 is lacking in certain areas and that other proposed standards are more
suitable for large, public networks. So call-control architectures such as session
initiation protocol (SIP), SIP Plus and multimedia gateway control protocol (MGCP) over
the past year or so appeared on the scene in an attempt to replace H.323–or at least fill
in the blanks.

VocalTec Communications Ltd., the U.S. operations of which are based in Fort Lee.,
N.J.; NetSpeak Corp., Boca Raton, Fla.; and RADVision Inc. USA, Mahwah, N.J., are the
three companies with which Cisco Systems Inc., San Jose, Calif., recently announced H.323
interoperability.

But interoperability is about more than just allowing different vendors’ similar
products to work together, such as gateways talking to gateways, notes Alistair Woodman,
group manager, packet-telephony applications for Cisco.

In line with that trend, Cisco at SUPERCOMM announced plans to interface with various
other companies’ products and services. Cisco says it plans to support the open
settlements protocol (OSP) on its gateways to work with clearinghouse/settlements provider
services from GRIC Communications Inc., Milpitas, Calif., and TransNexus LLC, Atlanta,
which are implementing OSP on their backend servers.