
What Makes the Thunderbolt Cable Lightning Fast - there
http://www.ifixit.com/blog/blog/2011/06/29/what-makes-the-thunderbolt-cable-lightning-fast/
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mostly_harmless
Can anyone explain why the chips need to be inside the cable? why cant they be
inside the hosting device port?

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Steko
[http://arstechnica.com/apple/news/2011/06/why-
apples-2m-thun...](http://arstechnica.com/apple/news/2011/06/why-
apples-2m-thunderbolt-cable-costs-a-whopping-50.ars)

"active cables are commonly used at data rates above 5Gbps. These cables
contain tiny chips at either end that are calibrated to the attenuation and
dispersion properties of the wire between them. Compensating for these
properties "greatly improves the signal-to-noise ratio" for high-bandwidth
data transmission."

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derefr
Instead of the cable actually managing this itself, though, couldn't the cable
just contain a single, simpler chip containing the metadata on the cable's
particular make and properties, which would allow the host port (and client
port) to perform variable compensation based on the information received? I
suppose this would create a more complex low-level protocol, or possibly
require more pins, but for a "universal connector" type of cable I imagine
they're going to see a lot of wear, so I would have imagined moving hardware
out of them would have been a goal...

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ary
Separation of concerns and flexibility for the future are probably what drove
this design decision.

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Daniel_Newby
It is probably cost. Motherboards are high-volume products, and therefore the
engineers who design them are fanatically cost sensitive. Adding $5 to the
bill of materials for a feature that hardly anybody needs would be a career
limiting move. Conversely, the people who actually need a 10 Gbps links are
exactly the people who can be up-sold to a $50 cable.

In a few years it will be everywhere natively: competition will have driven
the parts cost to pennies per board, and average customers will be demanding
it.

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tintin
Read the article and still don't know why it's lightning fast. All cables are
lightning fast.

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sliverstorm
Presumably these cables are _greased-lightning_ fast

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sliverstorm
I predict Monster Cable offers gold-plated chips in their cables

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trafficlight
I'm waiting for the Triple-Oxygen Free cables.

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pyre
For the uninitiated: electricity + O2 = O3 (aka ozone; aka that smell you get
from electric motors, e.g. electric slot cars).

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sjwright
Apologies for my layperson chemistry, but if the source of O2 is CO2, would
that explain the streaks of carbon residue on the track?

