The 1394 serial bus is a low-cost, high-performance, 100 percent digital serial connection for digital audio-visual devices, consumer PCs and home networks. It is the digital interface of choice for the transmission of digital audio-visual data for the consumer electronics industry with adoption by such products as digital set-top boxes, digital TV and digital VCR. With 400 Mbits/second commonly used today, 1394 is increasingly being adopted by PC manufacturers for peripheral interfacing. Currently eight out of the top 10 PC OEMs offer products with 1394. Over 20 million 1394-enabled end products have shipped through 1999, led by camcorder and PC systems.
As the base of 1394 products expands, the specification continues to become more robust and to deliver even higher bandwidth. With 800-1600 Mbits/s becoming available by the end of 2000, it is well ahead of the current bandwidth requirements. By achieving these data rates, 1394 can also expand into internal system interconnect sockets for products such as disk drives. Long-haul (100 meters) versions of 1394 are also being developed for multiple cable mediums (i.e. plastic and glass optical fiber and Cat 5). Finally an extensive infrastructure of application protocols are already supported by 1394 for PC peripherals, peer-to-peer audio/video transmission and control, as well as Internet Protocols. Collectively, these capabilities position 1394 as the convergence mechanism for consumer PCs, consumer CE devices and home networks.
1394 is a network solution that is available now that offers high speed, ease of use and low cost. The 1394 Trade Association has enrolled over 150 member companies. The development infrastructure is already in place and as more end products become 1394 enabled, the consumer will experience the strength of 1394, "connecting diverse systems with one network."
As early as 1986, Apple Computer, Hewlett-Packard Co., Intel Corp., National Semiconductor Corp. and others were investigating new serial technologies for next-generation computers, and thus the 1394 digital high-performance serial bus standard was conceived. The first specification was completed in 1987 and described an interface that ran at 1 Mbit/s and was intended to connect printers, scanners and external storage devices to computers. Over time, the standard evolved to include support for isochronous devices (e.g., cameras) and higher data rates (up to 400 Mbits/s).
The 1394 Trade Association was formed in the fall 1994 to further the development of the technology. With the goal in mind to bring about an open specification that was governed by an industry-recognized standards body, the trade association was successful in supporting the IEEE's ratification of the 1394 specification in December 1995.
Though the initial target devices for 1394 were PC peripherals, the consumer electronics industry proved to be the early adopters. In the mid-1990s the consumer electronics industry decided to go digital and it selected 1394 as the digital interface that would let it do that. As a consequence, the new digital generation of camcorders, TVs, VCRs, set-top boxes and audio products are implementing 1394 today. Digital camcorders were the first 1394 products to enter the market in the fall of 1995. Today, 1394-enabled camcorders are shipping from Sony Corp., JVC, Canon Inc., Sharp Corp. and Panasonic. In fact, according to industry insiders, 2000 will be the last year that new camcorders are produced without 1394. The target for many of these A/V companies is the 2000 Summer Olympic games.
In the computer industry there are 1394-enabled PCs from Apple Computer (G4s and iMacs), Compaq Computer Corp. (several models of the Presario), Sony (in every PC and notebook), Gateway 2000 Inc.(five models of notebooks) and NEC Corp. as well as several PCs and notebooks in Japan from Epson Co. Ltd., Sharp, Panasonic and Fujitsu Ltd. Off-the-shelf motherboards, PCI add-in cards and PC Cards are shipping today. Core chip-set manufacturers are integrating 1394 into their solutions and are expected to ship in 2000. In 1999, 8 million computers shipped with 1394, but this is just the beginning. In 2000, many more PC makers will ship 1394 models, with estimates of total PC adoption rates of 40 percent for desktop PCs and even higher for portables.
With support for PC peripherals in the Microsoft Windows 98 Second Edition operating systems, Windows Millennium Edition (Windows Me), and Windows 2000, along with Apple's Mac OS, peripheral devices are rapidly showing up in the market. PC peripherals including scanners, printers, external storage and desktop cameras are shipping today.
The work of literally hundreds of engineers has, over the last five years created a massive amount of supporting infrastructure for 1394. At the simplest level, the IEEE 1394 specification describes how to send information between two devices. The hard part is defining all the higher level protocols that use the connections to do useful things.
There are standards and specifications for virtually every type of consumer electronic device. There are printing protocols, scanner protocols and disk protocols, among many others, to handle the "traditional" PC peripherals. There are standards for providing content protection over 1394. 1394 provides excellent support for Internet Protocol. New standards like Universal Plug and Play (UPnP) and HAVi (Home Audio/Video interoperability) make networks easier than ever to construct.
UPnP allows devices to describe capabilities in a declarative fashion using XML and export user interfaces in HTML. Relying on these two Internet technologies makes constructing UPnP devices easy for systems designers, and removes the need for users to configure individual devices or add device drivers to systems. In contrast, HAVi allows the product designer to export user interfaces and driver-like control code written in Java to recipient devices. Although different in approach, both UPnP and HAVi will simplify the configuration of connectivity between 1394 devices for customers.
The existing and potential uses for 1394 span a wide range of applications. As a consequence, it is hard to say that any particular applications are the targets for 1394. This makes for a very exciting future. As 1394 continues to proliferate, the extended network of diverse end equipment will expand even further. Below is an abbreviated list of where 1394 is being used:
- Laptops, PCs, workstations and servers;
- PC peripherals;
- Consumer electronics and AV home networking
- Automotive and industrial;
- Audio visual home networking backbone.
1394 can support any mix of these applications simultaneously, and this versatility comes from the standard's rich feature set.
1394 is a multispeed technology currently running at 100, 200, and 400 Mbits/s. Next-generation silicon that allows speeds up to 800 Mbits/s is currently sampling. The latest version of the standard (1394b) doesn't stop there however, as it also provides the framework for fully backward-compatible 1.6-Gbit and 3.2-Gbit implementations.
1394b not only supports higher speeds but also provides the capability to transmit over longer distances. The current standard recommends a maximum cable length of 4.5 meters. The 1394b standard extends those distances by supporting optical cable lengths of 50 meters for plastic optical fiber and 100 meters for glass optical fiber and hard polymer clad, as well as 100-Mbit/s operation over lengths of up to 100 m on Cat 5. The capability to transmit data over these extended distances positions 1394 as the home-networking, high-bandwidth solution.
1394 provides for real-time data transfer that is called isochronous data transmission and guarantees bandwidth. 1394 combines this with excellent support for asynchronous transmission, which efficiently exploits all remaining bandwidth and provides guaranteed delivery.
The standard is a peer-to-peer technology, so PCs can talk to each other and peripheral devices can send data to each other without going through the PC. That is critical for use in consumer electronic devices, as one would want the PC to be able to work with a VCR and set-top box, without going through a PC. For example, digital camera makers are interested in sending images directly to a photo-quality printer without using the PC. This opens their market to people who do not own PCs or to people who would not know how to use the PC to make the connection from the digital camera to the printer.
The topology supports both daisy-chaining and branching. The simple rule is to find a port and plug in your device, with the restrictions of not forming a loop. The latest version of 1394 will automatically disable connections that make loops. A further restriction limits daisy chaining to not more than 17 devices. All 1394 devices are "hot plug-and-play" so the bus does not have to be power cycled after plugging in a new device and the PC doesn't have to be rebooted. All 1394 devices act as peer-to-peer repeaters, removing the need for special devices such as hubs.
A compelling advantage 1394 provides is power over the cable, so devices such as hard drives, desktop cameras and scanners do not require an additional power supply. Whereas other interfaces either provide no power or severely limit the amount of power supplied via the cable, most PC manufacturers today are providing from 12 W to 24 W of power over 1394. This eliminates the need for an external power brick for many devices, which not only reduces overall system cost, but also gets rid of the rats nest of wires plaguing today's systems-most of which are power cords.
Ideal road warrior
It might seem strange, but the ability of 1394 to carry significant amounts of power also makes it ideal for the road-warrior who carries his/her portable and some extra peripheral devices. With 1394, the peripheral can be powered by the PC's power supply or, in an emergency, the PC's battery. This reduces the weight that has to be lugged around as well as the cost of the devices (no extra power brick to buy).
To address the licensing issues surrounding 1394 intellectual property the industry has formed a 1394 patent pool. The patent pool is a collection of all the essential intellectual property that is required for 1394 implementation. Those companies with patents that are considered necessary and essential for the implementation of 1394 have released their rights to the patents by submitting them to the 1394 patent pool.
A 25 cent royalty is due for each system that is shipped and this is not a per-port royalty. It is 25 cents per system regardless of how many ports, parts or nodes are included.
This royalty is paid to the 1394 Licensing Authority (1394LA), which is the administrator of the 1394 patent pool.
What's with the name, 1394? That is the number of the IEEE standard that defines the technology. It is now being marketed under the brand names of FireWire (trademarked by Apple) and i.LINK (trademarked by Sony). The 1394 peripherals and consumer electronics products that work on an iMac will also work on a Windows-based system.
USB 2.0 is an excellent upgrade for current USB applications that need extra bandwidth. The end benefits of USB 2.0 sound similar to that of 1394: ease of use, PC peripheral interconnectivity and high bandwidth. Upon closer inspection, it becomes evident that the two technologies are fundamentally different and in different stages of development.
Foremost to the discussion is the fact that 1394 is available and shipping today at 400 Mbits/s with the features mentioned above, and development is well under way for further capabilities. This provides a compelling reason for PC, PC peripheral and consumer electronics manufacturers to implement the interface in support of the legacy-free and ease-of-use initiatives being promoted by the industry and demanded by the end user.
USB 2.0 is only now developing the transceiver functionality needed to send and transmit data between nodes, let alone the target and hub silicon devices that are needed to perform the basic network functions. Once device support is available, driver support is needed as well as the application protocol software required for specific end equipment.
Basic consumer applications for USB 2.0 are not likely before mid-2001. USB 2.0 has only just finished defining the specification. Silicon will take a year to develop, debug, test and go into production. Software will take an additional year.
In contrast, 1394 is fully supported by multiple versions of Apple, Microsoft and Linux operating systems. Further, 1394 has already achieved support for real-time AV transport, content protection and TCP/IP over 1394, let alone multiple demonstrations of wireless 1394 over lengths of 15 meters.
In terms of network implementation, 1394 is designer-friendly. The peer-to-peer network capability minimizes design considerations as compared to the PC-centric hub network of USB 2.0.
ALSO CONTRIBUTING TO THIS ARTICLE WERE COLIN WHITBY-STREVENS, ZAYANTE RANDALL TROST, TEXAS INSTRUMENTS INC.; DAVID WOOTEN, COMPAQ COMPUTER CORP.; BOB MOSES, DIGITAL HARMONY; AND DAVE SROKA, PHILIPS.