updated 01:30 am EDT, Tue September 27, 2011
Future cables promised for next year
Thunderbolt, already the fastest interconnecting system between computers and peripherals, may get quite significantly faster when new, optical-technology-based cables arrive on the market as early as the middle of next year -- and current Thunderbolt-equipped Macs will support them, says Intel. Spokesman Dave Salvator, speaking to MacWorld added that the optical cables could be significantly longer than the current copper-based ones, as well as faster.
Current Thunderbolt cables are able to carry up to 10 gigabits (Gb) per second in two bidirectional lanes, or up to 40Gb per second total throughput. Intel's original specification for Light Peak (as it was originally called) was based on the use of optical cables, which could reach speeds of 100Gb per second, though it was never specified if that was overall throughput or per channel. It's also unclear if TB-equipped Macs could take full advantage of the higher speeds, since the original vision was for an all-optical interconnect system, including internal components.
Still, current Thunderbolt technology, which incorporates both DisplayPort and PCIExpress, handily surpasses all the speed specs of both current technologies -- so the full potential of Thunderbolt may take several years to be fully implemented due to optical-cable cost limitations and the lack of need for greater bandwidth for quite some time, as stated by Intel Architecture Group general manager Dadi Perlmutter. The company does plan to release the first optical-based cables for Thunderbolt sometime in 2012, but they are likely to be quite expensive.
Optical cables, however, will also support far longer lengths than the current copper cables, Salvator said. They could be up to "tens of meters" in length, compared to the current three-meter (10 feet) limit. As the optical potential of Thunderbolt is explored, it may even be possible to use intelligent transceivers to further lengthen the signal. Current cables have internal firmware and transceiver chips on each end.
Though Thunderbolt has been slow to gain acceptance in the marketplace, Apple has offered Thunderbolt-equipped MacBook Pros, MacBook Airs, iMacs and Mac minis since earlier this year, with Acer and Asus both planning to add the connectors to some of their Windows-based PCs in the first half of next year. Compatible peripherals are also starting to appear, mostly in the pro-video arena but with a few enterprise and consumer storage solutions now shipping, including the Promise Pegasus RAID and LaCie's Little Big Disk Thunderbolt series.