Net broadcasts get a boost

A new addition to technology that aspires to alleviate current difficulties with multimedia broadcasts across the Net will be floated next week at the IP Multicast Summit, in hopes of adding much-needed reliability to the equation.

Cisco Systems (CSCO) and Tibco Software plan to float a protocol addition to the basic IP Multicast scheme that adds connection-oriented safeguards to ensure delivery of streaming content such as audio, video, or even software updates.

Bandwidth conservation is the primary goal in the development of IP Multicast, a technology that has been rapidly supported by providers of multimedia software programs, such as RealNetworks, Microsoft, and Intel. Unlike "unicast" methods, IP multicast-enabled networks send one transmission across a pipe that is then disseminated to many users at the end points.

Cisco and Tibco will introduce an addition to IP Multicast akin to the TCP (transmission control protocol) transport component of IP, the dominant communications protocol of the Net. The protocol, dubbed PGM (pretty good multicast) Reliable Transport, will be submitted to the Internet Engineering Task Force for adoption.

"Right now, the World Wide Web is completely focused on one-to-one communication," said Mark Bowles, chief technology officer at Tibco.

Tibco has created a niche for itself by providing software that disseminates real-time stock quotes to workstations within financial institutions, for example. What PGM adds is a component that either corrects flawed transmissions or alerts the user that there has been a problem in the process.

Release of the protocol will be one of the highlights of next week's multicast summit, being held in San Jose, California. Proponents in the effort to gain wider acceptance for IP Multicast will convene to discuss new developments. Martin Hall, chief technology for Stardust Forums, said 1998 should go down as the year service providers--the key to widespread adoption--implement multicast functions across their networks.

"We're at a watershed moment, not just for IP Multicast, but for the Internet as well," said Hall. "We have to take a serious look at the infrastructure and roll out technology that helps us realize those dreams we have for the Internet."

In conjunction with the release of the protocol, Tibco announced the availability of a preview version of its TIB/Rendezvous software that supports PGM. Cisco is also expected to include support for the protocol in the software that runs in its networking equipment.