The 1394 Trade Association Developer Conference continues today with Apple presenting its introduction to Mac OS X FireWire and LSI formally presenting an introduction to the 1394b specification. However, last night Apple hosted a demo room where about a dozen top tier FireWire vendors showed off their products and talked openly about future trends with FireWire and their take on
Microsoft’s eHome keynote presentation.
First and foremost, it was most striking how FireWire is now working in ways that were only 1394 specification protocols just months ago. Things like wireless 1394, 1394b, IP1394 and 1394 networking are all the rage. Yes, there were vendors showing off their latest FireWire drive enclosure and CD-RWs, but these products are almost considered a commodity by this developer crowd. To really get other FireWire developers excited, vendors felt the need to take FireWire to new and unusual places.
Wireless 1394 is intriguing. From the user’s standpoint, the device works just like an AirPort equipped Mac. Devices communicate with the PC via FireWire with no wire. Intel was demonstrating an HDTV that was being controlled remotely from a FireWire PC.
Here’s how Intel’s setup worked. A FireWire enabled laptop stored the images that the HDTV was to show and served them to another FireWire equipped laptop. This laptop had an 802.11 PCMCIA card (a lucent PC card similar to Apple’s AirPort cards), and the FireWire commands from the first laptop were translated into wireless signals. These signals were received by a third FireWire and 802.11 equipped laptop that translated the signals back into standard FireWire and finally sent them off to the HDTV, which happily ran through its slide show.
Because 1394 is a packeted standard for transmitting data (data sent along the 1394 bus is ordered into individual packets which are managed by the 1394 hardware and software), it is possible to embed these packets inside the packets used in the 802.11 protocol. The wireless FireWire hardware adds a collar around the FireWire packet, transmits the entire 802.11 packet with the standard FireWire packet concealed as data inside, and then strips the collar off when the wireless bridge has been crossed — sending the standard FireWire packet down the rest of the chain.
The software required to do this is extremely preliminary, and the two PCs in-between the first and the HDTV were essentially duplicating what wireless 1394 hardware will eventually do. The technology is at that gawky teenage stage, but it works and the design seems sound.
Intel’s proposed wireless 1394 method is reliant on the 802.11a protocol for the FireWire layer and the 802.11e for the hardware MAC layer. Most 802.11 wireless networking uses 802.11b, which handles both the hardware and software.
Also, there isn’t all that much of a fire to wireless 1394. Since it is based around 802.11, the maximum throughput is 12Mbits per second. Subtracting the data overhead from the collar reduces wireless 1394’s effective throughput to around 10Mbits per second. The target of the next iteration is to be over 30Mbits per second.
But, this has drawbacks as well. In order to transmit more data via radio, you must use a higher frequency signal. The trade off is that higher frequency radio transmissions have less penetrating power. Using a wireless standard for home networking is rather pointless if it cannot get to the next room. Additionally, increasing the power of the transmission brings its own host of issues as well.
The 1394 Trade Association is working on all of these issues.
Developing an effective wireless interface for home entertainment devices could reap rich rewards as it will fundamentally change how people set up their entertainment centers, stereos and other common household consumer electronics. No more wires in the living room; speakers and televisions using a wireless 1394 connection could be put anywhere.
Sony is expected to ship a 1394 (iLink) equipped HDTV in the very near future. In the demo room, four Sony PlayStation 2s were connected via iLink in order to play a network game. Because of the 1394 equipped products that are either shipping or soon to ship, everyone is looking for a common ground to network these products without a Mac or a PC.
Eric Anderson, Manager of FireWire software at Apple, gave a presentation yesterday afternoon on SBP-3 (Serial Bus Protocol 3). This is a 1394 software standard that is still in development, but will, when finished, be a performance improvement to the current FireWire software standard SBP-2. While his presentation was technical in nature, the intended major results of SBP-3 are to reduce arbitration between FireWire devices — thus reducing bus traffic and increasing performance while reducing the control load on the CPU, allowing bridges for improved performance between multiple FireWire chains and allowing true peer to peer device communication.
At one point, Anderson said during his presentation, it will be possible to connect one device, say a digital video camera, to another, say a hard drive, without a PC or Mac present. Anderson suggested that the CPU is not really good at transferring data in real-time. It is more efficient to transfer the data directly from device to device. Since the hard drive is essentially used as DV film, this type of transfer would save the user a great deal of time from transferring analog film data to the Mac or PC for editing. The data on the hard drive is ready for editing now, just remove the drive from the camera and plug it into the computer.
TCP/IP over 1394 is another hot topic at the conference. Called IP1394, this technology is attractive because it is a software translation of 1394 packets into TCP/IP packets. This allows networking of 1394 devices and PCs without any additional hardware — a great selling point to vendors. Also, this allows FireWire data to be sent over far larger networks, including the Internet.
Imagine, if you will, a Mac with no Ethernet jack. It is technically possible with IP1394 coupled with 1394b. The 1394b specification calls for top data transfer speeds of 1.6Gbits per second and even 3.2Gbits per second. You could use FireWire for both devices and networking and still have bandwidth to spare! This could blow away gigabit Ethernet and save Apple money by consolidating its hardware and simplifying motherboard design.
Sadly, this vision is a long way off. IP1394 is somewhat nascent, and only included in Windows ME and the upcoming Windows XP. However, it is gaining support from device makers and will be supported in all subsequent Windows versions. Apple refuses comment on all future products, and would not comment on whether or not it will include support for IP1394 in the Mac OS.
Another blow to this post Ethernet vision is the fact that the added data from the IP collar around the FireWire packets may soak up a good deal of the bandwidth potential offered by 1394b. This, coupled with the pervasiveness of Ethernet in the larger Internet world, may ensure that Ethernet remains the networking standard.
Apple representatives assured MacCentral at the conference that FireWire is essential to its Digital Hub vision. Apple refused public comment about their strategies using any of the above FireWire technologies.
Consumers ‘get’ using FireWire to connect devices to their Macs and PCs. But do they understand how FireWire may soon be used for much more than that? Apple is mum publicly on the subject, but it remains a driving force behind 1394’s development and future. Apple’s presence at this conference is immense — especially considering that the conference is happening at Microsoft’s conference facilities.
One developer who requested anonymity put it best. “1394b is a no brainer for Apple, as it is the natural evolution of the spec. The others are interesting, but the real question is whether or not a real application can be created. Consumer or developer demand is what helps Apple focus its development,” he said.