what is a map and why should i care?.?.

[jhay_19]

c/p

What is a MAP, and why should I care?

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First how digital scrambling works, quick version.
A digital picture or audio, is simply a bunch of numbers, when put together they make up the picture you watch or audio you hear.

Digital scrambling is easy you simply mix up the numbers, but to unscramble the picture you must know how it was scambled.
All sat TV providers use the same system to scramble, its called a Control Word system, easy term, they use a number like 03 c2 51 da 35 f5 ef 76 to scramble ONE channel for about 2 minutes, then they change the number, this number is called the CW (control word), they use a different number(CW) for each channel, it is just a random 8 byte number.

After they have scrambled the video with the CW number it is unwatchable, so their subscribers can't watch it either, so they must send out the CW to all their subscribers, and THIS is where encryption and decryption comes into the system.

This is what a card or cardless software is for, decrypting the CW for a specific channel, this is also why some channels will work and others won't, more on that later.

Ok so the picture is scrambled using a random number called the Control Word(CW).
Now to prevent anyone with a dish and digital receiver from watching their channels the provider must encrypt(hide) the CW using different prearranged math methods, the prearranged part is what they have loaded on their subscribers cards or receivers, they encrypt the CW using the reverse of the prearranged decryption on the cards, and this is where MAPs come into play.

A MAP is nothing more, or less, than a preset math formula.
add 03 to all numbers
sub 06 from all numbers
multiply all numbers by 04

All 3 of these are simplified math versions, each its own MAP.

So
MAP01 = add 03 to all numbers
MAP02 = sub 06 from all numbers
MAP03 = multiply all numbers by 04

Real MAPs are a little more complicated mathwise, lol.

But the process is the same, a MAP changes the CW number in a known way, known to DN.

DN tells the cards to use MAP57, then MAP03, then MAP3B in that order to decrypt the CW, if you don't know what the MAP does to the CW or you do it in the wrong order then you get the wrong CW at the end an no picture.
They also throw in a key or two (auto-roll gets one of those keys) in the decryption process just to make it a little more secure.

So pretty straight forward process, nothing real complicated about it, and very secure IF your cards are secure. This is why DTV is no longer a "freeTV" option, their new cards are secure.
There is no way to get around this type of scrambling you can either get the correct CW or you can't, the problem is the CW changes every 2 min. on each channel and no two channels will have the same CW.
You aren't going to just "guess" the CW for a channel, and even using the fastest computer on the planet you couldn't beat the 2 min. cycle.

If you read something that says they can beat this type of system without inside the card info, then put your hand on your wallet and back out of the room slowly, lol.

Because each channel basicly is running its own CW encryption they can run some channels on one CW encryption and other channels on another CW encyption, BEV is even using a different base system for NFL.
At any given time there are usually 2-4 different decryption paths available on a card, at this time BEV has 2-6.

In theory there could be 256 MAPs in a DN card, MAP00 to MAPFF, but probably not.

Just FYI, N1 and N2, and for that matter N3 when it comes, use the same scrambling of the digital picture, only the way the CW is encrypted and decrypted changes, so they can run multiple types of encryption at the same time, its only a few more CW packets every few minutes there is no bandwidth issue.

Now what has happened as of late, is that (Nagra Vision) has started impelmenting N3 into the stream, this itself is why we have all started seeing (private keys) example: nagra 01 06 00,for DN and B*V and 09 05 00,09 06 00,an 09 07 00.
Most of the time these's keys are not active, but as of late they Bev, and DN are trying to see just how far they can push there own receiver's and still work, most times itself is not but for a few hours at a time. but they are still continueing to work on it, making everyones life hard, including there own customers ofcourse.

Just remember that, unless Bev, and DN does a (complete system wide) upgrade of there whole (equipment, CAD Cards and Codes) at a cost of possibly a billion US dollars, only then can it shutdown FTA, and stop any coders from writting codes for all FTA units.

[bigapplefta]

nice thread. i been saying for a long time if an old 2700 ird can take the new cards and encryption. then a pansat or coolsat will have the power to do it also
just someone will have to figure out the new encryption so we can write the code. or we will have to use a iks type of system till we have that


thanks for a good read

[deerpoacher02]

good read jhay

good post.

[boner]

How can i read the ts stream and program my cnx

[acidcore]

Read the ts stream?
If you need to know how to setup your cnx, start a new thread in the CNX section please..I'll be glad to answer any qestion you have.
Please state which CNX you have and we'll go from there. But make sure you are in the proper section....which is here---->

Conaxsat Discussion - FTA-GODS.COM

[Error404]

Originally Posted by boner

How can i read the ts stream and program my cnx

You need to learn some programing and some soldering tools.

[boner]

Thanks for the reply error404 , im very good at soldering .what is the best program / logger /.......to use for testing.

[lift365]

Good post jhay, thanks