The 1394 bus in its 1394-1995 and 1394a versions provides speeds of 400 Megabits/second over distances of 4.5 meters. These performance capabilities that have led to 1394’s design into almost all high end camcorders and digital cameras, along with a long list of hard disk drives, printers, scanners, and other peripherals. Almost all new notebook PCs and many desktop versions also are now 1394-enabled. Some typical bandwidths for application are as follows: MPEG-2 for DTV requires, on average, 8 Mbps; typical IP transfer rates range between one and five Mbps; digital video in camcorders uses 25 Mbps; and high definition DTV requires approximately 20 Mbps. As a result, IEEE 1394a offers a high bandwidth network that can support many applications concurrently. North American analysts estimate that by the end of 2001, more than 60 million products worldwide were equipped with 1394. Projections now are for that number to reach 100 million – including PCs, DTVs, printers, drives and other products – by 2003.

Nor is the standard static. The 1394b version, detailed below, is ready for prime designs now, creating the basis for a comprehensive home network and enabling the base 1394 technology to expand into the automotive and wireless markets.

1394b technology builds on the strengths of 1394a and adds critical new capabilities, notably; added bandwidth – to 800 Megabits/second all the way, eventually, to 3.2 Gigabits/second. It incorporates networking capabilities over distances of 100 meters over CAT-5 and plastic optical fiber. It also improves overall network efficiency. These new features have been created with 1394a compatibility in mind, while maintaining the vital architectural characteristics of plug and play (PnP), peer-to-peer connectivity, and isochronous channels. This will keep 1394 in line with bandwidth demands currently required by CE, PC and peripheral applications, and ahead of competing standards.

For a 1394 network in the home, 1394 had to enable transmission past the 4.5-meter length originally set by 1394a. This is accomplished by 1394b, which also serves a variety of home network demands and potential requirements through a set of specifications for a multitude of cables. These include unshielded twisted pair CAT-5 cable; plastic optical fiber (POF); hard polymer clad fiber (HPCF) also known as glass optical fiber (GOF); and shielded twisted pair (STP). Each cable/ interconnect type is specified for specific lengths and associated data rates.

Finally, as the specification has evolved, numerous applications have been completed and introduced into the marketplace. During this process there have been some valuable lessons learned. These inputs have been incorporated into 1394b to improve network efficiency, and reduce implementation complexities. For example, arbitration control for transmission of packets has added a 1394b concept termed BOSS (Bus Owner Supervisor/Selector) so 1394b beta nodes can transmit data packets more efficiently, using less network bandwidth. From a chip design perspective, signaling has been simplified, so designs are less complex, which means improved robustness and lower cost implementations over time. Top