Friday, February 25


Thunderbolt and Light Peak

Ah, good work, Intel engineer dudes.

I'd heard of Light Peak, Intel's future desktop I/O technology set to replace USB and Firewire and eSATA.  I hadn't looked into it all that closely, and what I didn't realise is that it's a rejiggered version of DisplayPort.

DisplayPort is actually a modern display interface.  VGA is just a standard connector for age-old separate colour and sync connections.  DVI is digital VGA - it actually incorporates horizontal and vertical retrace intervals.  HDMI is just a different cable for DVI with a sideband for audio.

DisplayPort is a packetised 10Gbps (and more recently, 20Gbps) general-purpose I/O interconnect that just happens to be sold as a video connector.

Light Peak, now renamed Thunderbolt, extends this to offer two bi-directional 10Gbps channels per port that can carry PCIe and DisplayPort data simultaneously.  You can daisy-chain up to seven devices (including two 2560x1600 monitors) per port.  And the standard Thunderbolt socket is identical to mini-DisplayPort, and works as that if you plug a DisplayPort monitor into it.

Basically, it's just killed off USB 3, Firewire, eSATA, DisplayPort, HDMI, DVI, and 10Gbps Ethernet as far as the desktop goes.

And all I can say to that is it's about time.

There's one big limitation (apart from the fact that the only device supporting it right now is the new Macbook Pro): The maximum cable length for the copper version is just 3 metres - 10 feet.  To run longer distances, you'll need an optical cable; I don't know if that runs off the same port (by building the optical components into the cable itself) or not.

All in all it looks like a very nice - and very welcome - piece of engineering.

Update: Apparently, yes, the optical transceivers will be built in to the cable, so the standard port remains standard and you simply use copper cables for short runs and fibre for longer runs.

Posted by: Pixy Misa at 02:12 AM | Comments (4) | Add Comment | Trackbacks (Suck)
Post contains 322 words, total size 2 kb.

1 Now all they need to do is announce some hubs and cables, so we can see how much the future costs. My guess is that Apple expects pretty slow adoption for the next year or so, since they kept the FW800 port while promising that TB/FW adapters will be available.

Sadly, they released the sexy little 11-inch MacBook Air without this, so now I'll have to wait for the next rev of that hardware.


Posted by: J Greely at Friday, February 25 2011 06:40 AM (fpXGN)

2 In what way does a 3m long cable kill Ethernet? I can see desktop buses huring, but not Ethernet. Secondly, why did you include DP into the list when this _is_ DP? Only in the way USB 2 "killed" USB 1.1. The hyperbole looks like too much enthusiasm to me.

Posted by: Pete Zaitcev at Friday, February 25 2011 09:04 AM (9KseV)

3 It won't kill ethernet - no chance of that - but 10Gbps ethernet on the desktop is a different matter.  Though 10GBaseT will probably arrive on the desktop eventually, this provides a robust and flexible interconnect that removes much of the urgency.

It depends on where things go with drivers though.

And it is and isn't DisplayPort.  It's not just a matter of speed, but of protocols and capabilities.  DisplayPort could in theory be used for anything, but its back-channel capacity was way under-specified, so much so that it was almost unidirectional, and there was no standard for anything other than video. 

So this is more like...  More like...  Um.  Something else.

Posted by: Pixy Misa at Friday, February 25 2011 10:05 AM (PiXy!)

4 > So this is more like... More like... Um. Something else. Ignoring the display image transport, ThunderBolt seems to be a physical layer replacement for PCI Express External Cabling, since both use PCI Express logical protocols. InfiniBand and Myrinet come to mind as other interconnects that fill similar needs (just aimed at higher cost than the consumer space)

Posted by: Kayle at Friday, February 25 2011 07:12 PM (gpi2V)

Hide Comments | Add Comment

Comments are disabled. Post is locked.
48kb generated in CPU 0.0121, elapsed 0.1161 seconds.
56 queries taking 0.1079 seconds, 344 records returned.
Powered by Minx 1.1.6c-pink.