October 30, 2014

Is Everyone Wrong About Light Peak?

Light Peak Series

What is Light Peak? Images like this don't begin to tell the story of this next-generation interconnect!

Let’s get it out there right from the start: Light Peak isn’t anything yet; it doesn’t exist.

But I don’t think Light Peak will become the USB 3.0-killer that many folks suggest. Light Peak is a cabling spec only, not a new protocol that will eliminate everything that currently exists. In other words, Light Peak is a “middle connection” between a computer and peripherals that will retain compatibility with USB, HDMI/DVI, and Ethernet.

Light Peak Is a Cable Not a Protocol

A little background for the uninitiated: Light Peak is a collaborative effort led by Apple and Intel to develop a new optical connection to reduce the number of ports on next-generation computers and increase their performance. It uses a pair of directional 10 Gbps optical cables to carry existing video, storage, and networking protocols at incredible speed.

[yframe url='http://www.youtube.com/watch?v=nfGevFIVKw4']
Watch Intel’s Light Peak update from IDF

None of the official coverage of Light Peak suggests that it specifies a protocol designed to compete with USB, FireWire, HDMI, DisplayPort, TOSLINK, or any of the other ports and protocols found on today’s computers. In fact, all of the official information says just the opposite: “Light Peak is a new high-speed optical cable technology designed to connect your electronic devices to each other,” says Intel’s overview (emphasis added).

For the techies out there, Light Peak appears to be a simple OSI layer 1 technology. It must have some higher-level protocol to encapsulate different payloads and handle rings and loops, but it’s not any higher than layer 3.

The available Light Peak literature and demonstrations focus on the characteristics of the optical interconnect that is the basis of Light Peak. It leverages a simple, high-density connector along with inexpensive fiber optics and Vertical Cavity, Surface Emitting Laser (VCSEL) technology at 10 Gb per second.

Another key point made in the Light Peak presentation is that it “supports multiple existing I/O protocols over a single cable.” No need to decode this sentence: Light Peak is meant to carry existing protocols, not to replace them. How else would there be “no OS changes required” as the presentation claims?

In other words, Light Peak is all about how bits are moved and nothing at all about what those bits are.

Stephen’s Stance

Apple wants Light Peak, and Intel can pull it off. But the scarcity of information about the basic facts of the new connection belie their continuing claims that products will ship in 2011. Apple will likely produce the first Light Peak-capable machines (look for ‘em in a summer Stevenote) but peripherals will remain scarce for a while to come.

Light Peak will work out, but it’ll take a while longer. It’s time for the skeptics to change their tune. I also expect a further twist for Light Peak: Real plug-compatibility with USB 3.0. But we’ll have to wait until tomorrow for that discussion! Then there’s another though: What if Light Peak was electrical rather than optical?

  • http://etherealmind.com Etherealmind

    Why do you think that LightPeak is for external devices ? Wouldn’t LightPeak be a better replacement for SATA or other internal bus requirements to connect internal peripherals ?

    My bet is that LightPeak will be used internally first as a high speed device bus to replace USB2 for Video etc. Then later to be used for external devices.

    This would be more consistent with Apple’s strategy of testing in small quantity in a closed and controlled environment before ‘going large’.