Meridian Unplugged - Powered by MrTechGuy.co.uk Forums Discussion Meridian - Systems HDMI & HDCP

you are probably correct, gerald. any connected device could in theory be updated, but presumably such devices are "connected" via their "owners" (eg: sat receivers and cable boxes so they might be uncomfortable pissing off their customers - as opposed to if they were just sitting on the Internet talking back to Panasonic or Motorola or whomever.

fair point.

doody.

My understanding of the revocation policy works like this.

A display has a secret key - actually a set of keys. The unknown in this is the granularity of the display keys - maybe someone can enlighten me if this is per physical device (ie like a MAC), per product, per product type or per manufacturer. Someone has actually stated that it is per chipset.

As part of the HDCP handshaking, a source device validates the display key. The source also checks the key against a list an internal list of revoked keys held in prom. This list can be updated on the fly by data within the MPEG data stream. In theory, the revocation list could be added to the data stream given to say the broadcaster, so in the example above, Sky would not have any control over their box being disabled with the display device. So if you watch a DVD, or receive a broadcast that has a revoked key, the source must add it to its revocation list.

So basically, the source, DVD player, STB etc will nolonger work with that display device. The display device will still work with other sources, unless that too had received a revocation device.

As I said above, the unknown is whether the source will stop working with only that physical display, or all displays of that model, or type or manufacturer or chipset.

-Ian

if that's true, ian, that'd be pretty annoying.

all this idiocy does virtually nothing to prevent piracy and serves in the end only to annoy the honest users.

very frustrating.

the music industry has already seen the wrath of the public when they mistreat their customers. the video industry is going to get treated similarly if they too treat their honest customers as criminals.

DRM almost uniformly works in a "guilty until proven innocent" world.

i don't steal music and i don't steal videos. but i get screwed because i can't play my iTunes stuff on non-apple products and i get screwed because my HD television doesn't support HDCP. stupid.

at some point it'll be easier for me to just start stealing the stuff, and that's a shame.

doody.

"As I said above, the unknown is whether the source will stop working with only that physical display, or all displays of that model, or type or manufacturer or chipset."

I am still a little foggy on this. If it is only that individual physical display that has been successfully compromised then presumably the revocation system wouldn't know it from an uncompromised one assuming all the handshaking protocols were the same. If so, that would imply that all units of that model would have to have their license revoked. To me, that sounds like class action paradise for lawyers.

Unless of course there is sticker on the box of your player that states "By breaking this seal, you agree to be bound by an agreement of encyclopeadic breadth and complexity that basically means you can enjoy this product until we say you can't, with no implied rights of ownership or recourse whatsoever."

I have had an email back with answers to some fairly unambiguous questions from the technical support department of the manufacturer of the product discussed above. The questions relate not to the above product, but to an HDCP compliant DVI->VGA converter.

To be honest, the answer to Q4 makes a mockery of the concept of device secret keys and system renewability messages used to revoke the device keys/non secret identifier (KSV). IMO, a single device being compromised should not affect other uncompromised devices.

Hopefully someone with a little more knowledge can enlighten us all.

[This message has been edited by ianh (edited 04-04-2005).]

I've found HDCP is triggered (over HDMI/DVI)if the video DVD is copy protected. One way round this HDCP crap is to strip the copy protection off the DVD and make a new copy! BUT ....... why not just use a BX case computer (or a laptop with sound out_?! (BX cases are more portable).
The original problem was an LCD screen that seemed not to be HDCP compliant with a G91.
Works with a computer .............!!!!!

AnyDVD will strip the copy protection on the fly as you play the disc so no need to even copy it.