Digital Television DTV

[Jan Panteltje]

Hi Jan,

That sounds like a pretty antiquated scheme. Why can't they send a
common code for all channels and then the card only lets those be active
that the subscriber has paid for? Could be rotated regularly to avoid
cheats, like the rotating code on garage door openers.

I very strongly recommend you read some official documents on this.
It is a very good and cryptographically correct system.
It makes no sense to continue the conversation on the crypto used unles you
fist read up on some of the basics used.
Start by reading apres_1.pdf (google), look at the crypto system block
diagram, ECM EMM.
Then read the http://www.ee.udel.edu/~heredia/Papers/CApaper.doc
There are a lot of references at the end.
Of cause you can carry on and disagree endlessly in newsgroups, but it is
no fun experience YOU must learn if YOU want to understand the subject.
Best way to learn is to implement such a system, so... have fun.
JP

 

[Terry Given]

Hi Jan,

Thanks. Seems prices do start to come down even here in the US. $199
plus $19 for the remote isn't bad at all.

The only thing you need with this one is a PC in the living room.
Despite all hype in the media this hasn't happened yet. It would have to
be a silent PC where you can't hear fans or hard drives. Most of all,
one that does not crash which means it cannot run the usual consumer
grade op systems. Technically possible but the industry has to get that
into their heads first.

Now we'd need a module like that with an integrated converter and
modulator to bring it all into a regular TV, or at least with a standard
output that the new screens can take without the need to have a PC in
between. That should not be a big engineering deal either.

Regards, Joerg

And dont forget the most important feature: It should start working as soon
as you turn it on, and stopping it should be no more complex than turning it
off at the wall.

I was horrified at the first HP/agilent scopes to include Windoze.....

cheers
Terry

 

[Terry Given]

Hi Jan,

Agree than Linux is better than Windows. But again, think consumer here.
If they can buy a PC that does all the stuff they want with Linux, ok.
But currently most of them can't. Placing the PC in another room? Drill
holes in the wall? Then hear that hiss from the water pipe your drill
just hit? Regular consumers are not going to do that. In our case there
even is no room next to where the TV is located. It would sit in the
rain and snow.

We don't have SCART here but most TVs are equipped with RCA jacks for
audio and video. And no, people do not want to buy a new TV for HDTV if
some program only airs in that format. They will want a box with some
gizmo in there that converts from HDTV to SDTV. And they don't want to
know how that works, just that it can be bought cheaply at Walmart and
gets the football game onto the TV. This is how many consumers think and
engineers have to please them by developing that stuff.

Regards, Joerg

And all the consumer should have to do is unpack it, plug it in and turn it
on.

people who care about PCs will always be able to make systems work. Me, I
long since stopped caring. I just want spice, mathcad, matlab and protel to
run. other than that my PC is of no interest to me

Cheers
Terry

 

[Terry Given]

Hi Joel,

This would be nice. If you have some links these may be useful to many
here in this NG.

Some day there needs to be a silent PC in the affordable "Walmart
category". That's what really drives technology into the living rooms.
Even TiVo didn't quite make it. Our neighborhood with quite a few
retirees (disposable income is there in many cases) hasn't seen one yet.
But everybody except us appears to have a couple thousand or so invested
in a huge TV. Analog ones. They will not part with these, meaning
anything that is going to be sold either as technology or as media
content needs to play on these large analog screens.

Regards, Joerg

the geeks I work with have suggested X-boxes with mod chips as ultra low
cost PCs. Betcha Micro$haft hates that idea....

Cheers
Terry

 

[Joerg]

Hi Terry,

Same here, Terry. Except that I also stuck to some DOS stuff because it
is much more reliable. But I do not want to know how the innards of my
PCs work. As long as they do work.

Simplicity and functionality is what many industries do not understand
and it is usually the reason when a whole concept fails in the
marketplace. Such as X10. A wonderful idea but it has never made it into
widespread use.

Regards, Joerg

 

[Joerg]

Hi Terry,

Yup, right on. I was equally horrified when I saw med gear with Windows
that had to be "shut down orderly". I was pretty hardnosed in vetoing
that kind of "technology" and it was a tough fight on my part. Until one
of the SW engineers saw it: A hospital technician switched off our unit
at the power strip. The guy turned pale but nothing bad happened, since
our machine was ruggedized against that. The competition was not that
lucky and lost oodles on warranty service calls.


Regards, Joerg

 

[Joerg]

Hi Jan,

Thanks for the links, the Apres-1 presentation is a really nice summary.
What I miss on the CA paper and others is some critical review of
upsides and downside. Not just upsides. This is necessary in any
engineering process and it is dangerous to just leave it out.

All I have tried to do in this thread is something that gets hammered
into us med electronics guys: Think like the customer and ask the
customer. Else the competition will do that and eat your lunch.

I could tell you a lot of horror stories about what happens when
engineering teams neglect that rule, anticipating that customers are
always willing to gobble up any kind of new technology. One thing I am
pretty sure about: 5-10 seconds of CA authentication is not going to
fly. It will drive people up the walls and then to the phone, to cancel
and elect the 30-day money-back guarantee.

Regards, Joerg

 

[Jan Panteltje]

Hi Jan,

Thanks for the links, the Apres-1 presentation is a really nice summary.
What I miss on the CA paper and others is some critical review of
upsides and downside. Not just upsides. This is necessary in any
engineering process and it is dangerous to just leave it out.

All I have tried to do in this thread is something that gets hammered
into us med electronics guys: Think like the customer and ask the
customer. Else the competition will do that and eat your lunch.

I could tell you a lot of horror stories about what happens when
engineering teams neglect that rule, anticipating that customers are
always willing to gobble up any kind of new technology. One thing I am
pretty sure about: 5-10 seconds of CA authentication is not going to
fly. It will drive people up the walls and then to the phone, to cancel
and elect the 30-day money-back guarantee.

Well, it has not happened here in Europe yet.
Today I did see a 99Euro FTA sat receiver that switched channels in about
100ms it seems.
So.. but for the crypto it will never happen./
What makes you think there was no design review, it is even mentioned in that
second paper!
When we talk about standards, well a DTV system had to be designed, acceptable
to everyone.
When you stay with one 'bouquet' with one crypto system, you can switch faster.
But see, we have hundreds of satellites, with some hundreds if not thousands
of channels per satellite, it is not like that US one little bird like stuff ;-)
Remember the US is many years behind.... and slowly dissapearing from view...
Your chance to design and get concensus for a better crypto system for 20
years from now!
sci.crypt.
Ask about triple DES, pro and cons.
Use google perhaps to find out more, I am under non-disclose about the propriatary
systems.... US tortures prisoners, so... be careful.
hehe
JP

 

[Joerg]

Hi Jan,

Design is the easy part, consensus is the tough part. I just don't want
to get involved in standards work unless I have to. Did a little
(medical), didn't enjoy it. Too much politics, special interest, strong
arming and so on.

The "bouquet" approach for CA could work for digital television if, and
that's a big if, a censensus could be reached. But with the number of
sources you mentioned this almost requires a large organization taking
the lead here. In the US that would be IEEE, in Europe I wouldn't know
since each country tends to have their own. Maybe an IEC committee?

US behind in DTV? Over here people do not think so, and even many in
Europe don't. They often point out the fact that Europe still doesn't
have much to write home about in terms of HDTV programming and content.
But hold the tomatoes, I have no opinion on that. TV just isn't
important enough for me. It just makes me a bit sad every time parts of
the world decide on different standards. There is no technical need for
that. I guess it's politics and that's not my kind of turf, at least not
for technical matters.

Just FYI, here is an interview with the CTO of Loewe who corroborates
that opinion. And this is a European. Unfortunately it's in German but I
hope you can read anyway:

http://www.eetimes.de/showArticle.jhtml?articleID=20800015

Design reviews: Yes, I know you guys are doing that. Just one small bit
of advice: Get the end customers in on those very early on. Let them
test drive stuff. If you don't there is a huge risk of non-acceptance.
Hard lessons learned in med electronics where we always have customers
in that loop. They are high quantity users of the equipment and are
often paid for being advisers. Wouldn't design a thing without them.

Regards, Joerg

 

[Jan Panteltje]

Just FYI, here is an interview with the CTO of Loewe who corroborates
that opinion. And this is a European. Unfortunately it's in German but I
hope you can read anyway:

http://www.eetimes.de/showArticle.jhtml?articleID=20800015

Quote:
Schaas: Grundsätzlich ist der DVB-Standard eine ziemlich zentrale
Angelegenheit. Das ist ein erfolgreiches Projekt weit über Europa hinaus.
--------------------------^^^^^^^^^^^^^^^
Das HDTV-Format muss in Europa ebenfalls dringend kommen. Die
Geräteindustrie ermuntert ständig die Programmanbieter, Schritte in dieser
Richtung zu unternehmen, bislang aber noch ohne durchschlagenden Erfolg.
Zusätzlich ist die Multimedia Home Platform (MHP) von großer Bedeutung.

end quote


I am familiar with Loewe, as I have serviced many of their TV sets...
(I had a TV repair shop).
He (Schaas) seems to be a bit unhappy that there is Viaccess(2), Seca(2),
and a few more crypto systems, if so he misunderstands the reason, this was
designed in.
Maybe he just does not want to pay the licensing.
As for HDTV, are YOU bothered by the lines in a 800x600 progressive display
on you PC (you must have a PC)?
I really think it will be difficult to sell HDTV here... mostly people are
happy with 720x576 PAL!
As for the TV with internet connection, I think he is wrong there too,
because there is not enough bandwidth atm.
Digital terrestial TV in Germany is being phased in right now, and I expect
the analog station to disappear.
In the old days Loewe sometimes had the latest technology in their TV sets,
but that is selling in a niche market, most people did not care WHAT was
in the set, more how it looked and worked.
Some one at Philips (he never mentions Philips research in flat panel, now
for example with droplets on 'TV paper', so he is likely a bit pissed
with the competition!) said about the(ir) first digital processing TVs
(I still remember this) 'What good is it to make signal processing digital
if all it gives is more hum in the sound'. And the Philips sets had analog
sound of extremely good quality. I know, I worked for them.
So, it is a one-sided interview, not very inspiring.
Companies like Grundig had a hard time, once were part of Philips, things
change...
It is indeed a very very difficulty market now that you can buy a TV with
teletext from the East for 200Euro!
You can say 'I want to manufacture here' but that would be the end of the
business.
Or you would have to have such an exceptional product, but the fun thing
with digital is that once the chipsets are out, EVERYBODY and their cat has
that 'exceptional' product!
Now we see China going EVD (new blue light DVD standard) and that may not
be the last time! When they came with CVD there was a big panic in Philips
and the answer was SVCD, not better, no, but different.
If you look at these aspects then wages will have to drop here, to make
manufacturing competitive, and same for the US, or no company will be left
here.
I get emails for software development from Russia for 10 Euro / hour.
They do it for you, very tempting!
I think Kerry in the US is also concerned with the job loss.
What is the alternative? War?
Start manufacturing weapons? The Bush way (Or Hitler did the same).
So, in the most positive view, economics would level out.
But in the more likely case perhaps there will be a shortage of resources,
now in Germany there is some big thing going on about alternative energy
sources, they even want to use coal, it will last longer then oil...
I did read 80 years for oil..
So, most likely is there will be a big fight, someone will start, after that
back to the tents and wood fire... climate change, one big movement of
people across the globe, we are lucky (I am) lived most of my life in peace
and without major natural catastrophes. Apres moi le deluge!
In the end the sun will go out, and the future generations better have found
a way out of here, else it is all over!
So what can be learned from this?: Have fun now.
JP

 

[Georg Acher]

|> I could tell you a lot of horror stories about what happens when
|> engineering teams neglect that rule, anticipating that customers are
|> always willing to gobble up any kind of new technology. One thing I am
|> pretty sure about: 5-10 seconds of CA authentication is not going to
|> fly. It will drive people up the walls and then to the phone, to cancel
|> and elect the 30-day money-back guarantee.

The 5-10s delay are rare. They occur only when changing transponders _and_ the
provider. For one provider (like Premiere in Germany) it is usually faster, but
it depends also on the STB. There are slow ones that even need 3s without any
encryption. The ECMs (which carry the encrypted key) can be sent every second or
so, so in the end it's just the key decryption in the CAM (sometimes a good old
8051...) and the re-sync to an I-frame on MPEG that take most of the time.

On the other hand, the encryption system has a few nice features. Since only the
decryption of the descrambler key is primarily handled by the CAM, you can use
"virtually" more than one CA system (Simulcast). So when changing to a new
system, you don't have to do a hard CA switch with all the logistical problems
for the customers. Premiere did this when their CAM system was hacked, they used
the old and the new system in parallel for a few months.

Currently, only a few CAM decryption systems were hacked and are now longer in
use. The whereabouts are unclear, but looking at the source code eg. of
Betacrypt/Irdeto, it looks more like a social leak or a fool's implementation...

The common scrambling algorithm itself (CSA, http://csa.irde.to/) seems quite
hard to break. But if someone finds a hole in it, ALL pay-TV providers in
Europe have a really HUGE problem ;-)

 

[Terry Given]

Hi Terry,

Same here, Terry. Except that I also stuck to some DOS stuff because it
is much more reliable. But I do not want to know how the innards of my
PCs work. As long as they do work.

Simplicity and functionality is what many industries do not understand
and it is usually the reason when a whole concept fails in the
marketplace. Such as X10. A wonderful idea but it has never made it into
widespread use.

Regards, Joerg

Hi Joerg,

I read an interesting article once by a guy at HP who was basically a
psychologist. His thesis was that multi-purpose machines (PC of course being
the worst example) are terrible. The argument was that complexity rises
faster than the number of functions (have to choose which function etc) and
pretty soon things get out of hand. eg a simple scientific calculator -
trivial to do calculations with. But a PC is much harder, and M$ calculator
(which doesnt have a sqrt() button in scientific mode is an absolute pig
to use. And with increasing complexity comes the spectre of increasing
unreliability.

Cheers
Terry

 

[Joerg]

Hi Georg,

Three seconds or even more are ok when customers know that a certain
movie that they always wanted to see is about to start on the selected
channel. In that case even I wouldn't have a problem with that much wait
-.

The problem starts when someone is just hopping channels to find a
program to watch. It's sad but some people just can't find anything
better to do. In a hotel you are stuck, you have to take whatever TV
setup they've got. But at home that will very soon cause the old
fashioned cable providers to pick on the waiting time. They'll structure
their ads around any kind of weakness or perceived weakness they can
find in the competitor's system.

I have seen this happen with DSL versus cable Internet. DSL out here
comes via dynamic IP which often means you'll get kicked off after some
time of idling. Quite the contrary to the "always on" promise. Sometimes
the only way to get back on is to power cycle the modem and wait through
1/2 minute or so of re-sync. So, cable Internet offered "true always on"
and many of our neighbors switched. The reason why I didn't is that
cable had higher rates unless you also take their TV which I won't. The
others just got tired of these wait times and my guess is that the loss
of biz that has caused must be substantial, considering that broadband
cost about $50 a month.

Regards, Joerg

 

[Joerg]

Hi Terry,

That psychologist is absolutely right. It affects everything in life.
And simplicity is the reason why I bought a car that had the least
gizmos possible. The upside was that this also meant the lowest possible
price. Neither the dealer (!) nor any of our neighbors understood how
one could buy a car without power locks, windows etc. Until one of them
got stuck at the shopping mall and the window wouldn't roll up anymore.
An abrupt end to a shopping day because nobody in their right mind would
leave an open car there. The wife was miffed, the kids were cranky and
basically the whole day was shot because of too much "gizmology".

Then ask around how many people can program their VCR. Too complicated.
On top of that this industry has to a large extent still not figured out
how to make the clock stick through a power outage. I don't know what's
so difficult about that.

This will make the HP psychologist happy: I have never used the PC
calculator but always the HP11C. The first set of batteries lasted a
whopping 15 years. So maybe I'll be on the third set by the time I
retire. At under $3 a set not a bad deal at all and you can get them at
the local supermarket, two aisles down from the beer. Did I ever use the
programming functions? Nope. All the formulas I need for electronics are
in my daytimer. In "pre-Gutenberg" style, hand written.

Regards, Joerg

 

[Tim Auton]

That psychologist is absolutely right. It affects everything in life.
And simplicity is the reason why I bought a car that had the least
gizmos possible. The upside was that this also meant the lowest possible
price. Neither the dealer (!) nor any of our neighbors understood how
one could buy a car without power locks, windows etc. Until one of them
got stuck at the shopping mall and the window wouldn't roll up anymore.
An abrupt end to a shopping day because nobody in their right mind would
leave an open car there. The wife was miffed, the kids were cranky and
basically the whole day was shot because of too much "gizmology".

I've experienced the same problem with manual windows. Was that too
much "gizmology" too? In fact, power windows are not an increase in
complexity for the user. Turn clockwise or anticlockwise is translated
into push down or pull up. Central locking isn't an increase in
complexity for the end user either. Instead of having 2^5 = 32
possible independent states (4 doors + boot/trunk locked/unlocked) you
have 2 - locked or unlocked.

Then ask around how many people can program their VCR. Too complicated.

Here in the UK most people with recent VCRs program it with VideoPlus
(you type in the number listed in the TV guide) or by selecting your
program from Teletext. That's far easier than it was 10 years ago. The
latest gizmo is the Sky+ box - a PVR from the main satellite TV
provider in the UK (think TiVo with two tuners and a better EPG). That
is far easier to use than a traditional VCR, but also more flexible.

On top of that this industry has to a large extent still not figured out
how to make the clock stick through a power outage. I don't know what's
so difficult about that.

It's not difficult, just more expensive. If consumers decided not to
buy VCRs because the clock didn't survive a 72 hour power outage they
would all be designed to survive it. But consumers don't do that.

The HP person made some good points, but I think you're talking about
something else.


Tim

 

[Paul Hovnanian P.E.]

the geeks I work with have suggested X-boxes with mod chips as ultra low
cost PCs. Betcha Micro$haft hates that idea....

Particularly when that mod chip is a Linux boot rom.

 

[Terry Given]

Hi Joerg,

Hi Terry,

That psychologist is absolutely right. It affects everything in life.
And simplicity is the reason why I bought a car that had the least
gizmos possible. The upside was that this also meant the lowest possible
price. Neither the dealer (!) nor any of our neighbors understood how
one could buy a car without power locks, windows etc. Until one of them
got stuck at the shopping mall and the window wouldn't roll up anymore.
An abrupt end to a shopping day because nobody in their right mind would
leave an open car there. The wife was miffed, the kids were cranky and
basically the whole day was shot because of too much "gizmology".

hear hear! And with a simple car, you can repair it yourself, rather than
having to take it to the priesthood. Several of my friends have had horrific
experiences trying to get high-tech problems repaired - such as dodgy ICs in
power steering controllers. In that instance she was lucky, because she
boguth the car from a reputable dealer, and had enough understanding of
consumer law to FORCE them to repair the car. It still took a year for them
to find the real problem (IIRC it was a dead ULN2003) that caused the car to
pull to the left strongly. Most mechanics cant deal with this stuff.

Holden had a dreadful run just recently in Australia - dodgy car computers.
Cars would do things like refuse to unlock, or start etc. when T got too
high - as it tends to in the outback. Ya cant crash-start them new-fangled
gizmos.

OTOH complex engine controllers can significantly reduce pollution. OTOH we
compensate by driving tanks when minis would suffice (and damn those new
mini coopers go fast PS - did you see the robot the pommy PhD built out
of mini parts? It can catch a land rover.....

Then ask around how many people can program their VCR. Too complicated.
On top of that this industry has to a large extent still not figured out
how to make the clock stick through a power outage. I don't know what's
so difficult about that.

when I lived in the US ('97-2000) there was much discuccion about so-called
self-adjusting clocks - they use a time signal that is broadcast along with
the content. Problem was, if a west-coast show was played on the east coast,
and the service provider didnt strip the "old" timestamp and replace it with
the correct one, VCRs automatically re-set their clocks. And you cant stop
them doing it....exactly the sort of so-called "brilliance" I expect from
software - the idea is great, but the implementation aint.

This will make the HP psychologist happy: I have never used the PC
calculator but always the HP11C. The first set of batteries lasted a
whopping 15 years. So maybe I'll be on the third set by the time I
retire. At under $3 a set not a bad deal at all and you can get them at
the local supermarket, two aisles down from the beer. Did I ever use the
programming functions? Nope. All the formulas I need for electronics are
in my daytimer. In "pre-Gutenberg" style, hand written.

Regards, Joerg

My favourite piece of software is an eraser. I do almost all my calculations
by hand - certainly all the 1st-order calcs. And I document by hand too
(along with printouts, scope snapshots etc).

Mind you, I once wrote an astonishingly lazy program in matlab. I was
re-engineering smt resistors for a new product (our prod guys said we could
have as many values as we wanted, so we did. Then they changed their mind).
For each R I used R||R||(R+R) from a very limited set. To pick the "best"
network for each R, I basically calculated every combination of the values
at hand, for each of the 4 topologies, then sorted the results for each
topology in descending order of accuracy. Listing the top 10 results for
each topology I could thus pick the best combination. Of course my PC did a
few billion calculations to choose 100 "new" resistors, but who cares

cheers
Terry

 

[Terry Given]

Particularly when that mod chip is a Linux boot rom.

ROTFLMAO!

can this actually be done? I just love adding insult to the fiscal injury
(M$ sells x-box way below cost)

Cheers
Terry

 

[Tim Auton]

Terry Given wrote: [snip]

the geeks I work with have suggested X-boxes with mod chips as ultra low
cost PCs. Betcha Micro$haft hates that idea....

Particularly when that mod chip is a Linux boot rom.

ROTFLMAO!

can this actually be done? I just love adding insult to the fiscal injury
(M$ sells x-box way below cost)

Oh yes, and you don't even have to do any soldering (but it's more
flexible if you do):

http://www.xbox-linux.org/


Tim

 

[Iwo Mergler]

ROTFLMAO!

can this actually be done? I just love adding insult to the fiscal injury
(M$ sells x-box way below cost)

Cheers
Terry

http://www.xbox-linux.org/

:^)

Iwo