The benefits of 1394b take the technology to a higher plateau in terms of use and expandability. To achieve this outcome, the 1394 architecture was altered to navigate across the generations. Since 1394 specifications are constructed in layers, it was important that 1394b incorporate no changes above the link layer, so that an application is not dependent on any specific generation of 1394 technology, and will not require re-engineering or further design work.

To achieve this transparency, 1394b’s developers created new physical constraints so the new versions are compatible with existing ones. As a result, one new port has been introduced, called a ‘bilingual’ port, a physical structure included in end-use equipment. New connectors also have been introduced. The first is a bilingual connector, which links physically to a bilingual port and ‘speaks’ either 1394a or 1394b signaling. The other is a beta connector, which connects physically to a beta-only port and ‘speaks’ only 1394b signaling. The addition of new connectors means there are now these cable combinations: bilingual and 1394a 6-pin; bilingual and 1394a 4-pin, and beta to beta, which will be used in future applications.

The current installed base of 1394a-equipped products is generally segmented: the 4-pin port/connector is typically used in a camcorder, and the 6-pin port/connector is used everywhere else, including personal computers, DTVs, DVDs, and set-top boxes.

This might seem complex, but the end result is easily quantified. For new equipment, designers will choose what works best for their application, which means analyzing availability, cost, distance needs, and bandwidth requirements. The result will yield the type of ports to put on the system (Bilingual or 1394a 6-pin). For the end users, the issue is simple: they must have the correct cable and/or appropriate adapters. Over time, these alternatives will converge, as equipment moves to the ‘b’ version of the standard.

The issue of long haul, ports, and connections also is important. The anticipated configuration consists of standard 1394b connections between the end equipment and a wall outlet, with cable-specific requirements housed in the outlet. This means the impact of these decisions is not left to the consumer but resides with construction and contract personnel working on home building and rewiring. Top