When Intel demoed its Light Peak technology last year it blew many a mind. Building upon years of work in Silicon Photonics (semiconductor based lasers) it delivered a massive 100Gbps throughput over a single optical cable. Since then all sorts of rumours about Lights Peak have landed, from it being designed at Apple’s behest to it losing the laser part in its initial, much earlier than expected, deployment.
It turns out that the rumours were indeed true. For Intel has just announced that the technology once known as Light Peak has landed. Now called Thunderbolt, it can be found on Apple’s new range of Macbook Pros, and only there, as it has also been revealed that the technology will be exclusive to Apple until 2012.
The rumours about the switch from optical to copper are also true. Thunderbolt uses standard copper cabling, which means that a lot of the sheer awesomeness of Light Peak is gone. There is a limit of 3m to cabling, where optical effectively has no limits, and the maximum throughput has dropped tenfold to 10Gbps – still impressive but only double that of USB 3.
What really is ingenious is Apple and Intel deciding to pair Thunderbolt with Displayport, which is finally getting traction outside of Apple products (and is ironically being spearheaded by Intel’s main competitor, AMD). The latest Displayport specification allows for the daisy chaining of monitors, and surprise, surprise Thunderbolt is also designed for daisy chaining. A single Thunderbolt port can run up to six devices, including two monitors.
Double the throughput of USB 3.0, but exclusive to Apple till 2012.
Part of the inherent flexibility of Thunderbolt comes from its PCI-Express origins. Both technologies were developed by Intel, and while PCI-Express is the de-facto PC interconnect on both Intel and AMD systems, Thunderbolt actually requires the use of an Intel chip to work (we have asked Intel for some clarification on whether Thunderbolt will be possible on non-Intel systems and are awaiting an answer). This chip takes both x4 PCI-Express and Displayport signals and combines them into a single stream. This stream is then decoded by an Intel chip on the other end of the cable and split back into PCI-Express and/or Displayport.
There are many advantages to this, the biggest of which is that because the computer sees Thunderbolt devices as PCI-Express ones there is no need for special interface drivers like there is with USB. It also ensures future scalability of the technology – PCI-Express’ Lane based construction was designed from the ground up to scale as bandwidth needs increase simply through the addition of more lanes.
It is important to also note that this isn’t the death knell for USB. Thunderbolt is targeted at devices with high bandwidth needs – an external hard drive, for example, is still limited by the speed at which its platters spin, and USB 3 has more than enough bandwidth for it. The only Thunderbolt peripheral announced so far is Lacie’s Little Big Disk, which uses raided SSDs in order to deliver the kind of speeds promised by the technology.
We have asked a few more questions of Intel and will be checking out the new Macbook Pros later today. Until actual peripherals hit the market though we will have no real idea of how Thunderbolt will perform in the real world.