How does satellite decryption work

In practice, things go that way: Each subscriber has a smartcard, and that card contains a key K s specific to that subscriber. The media stream is encrypted with a key K. That key is updated regularly. Along with the media stream, the publisher sends K encrypted with each K s in circulation. That is, every minute or so, thousands of small blobs are sent in some "holes" in the data stream apparently there is sufficiently free bandwidth for that ; all these blobs contain K , but encrypted with the key of a subscriber.

Improve this answer. Thomas Pornin Thomas Pornin k 57 57 gold badges silver badges bronze badges. I was reading up on Broadcast encryption and quickly got overwhelmed. If you know of any roadmap to getting from this description to the next concepts I should learn, I'd be very grateful — Christopher Jon Mankowski.

The article you link to is extremely formal and theoretical; beginning with it is hardly recommended. For a more practical description of AACS, try that one. I'm not an expert in encryption but if you were to decrypt signal then it is definitely not the Smart card where you should look at.. This is just some extra information but it didn't fit as a comment under Thomas' answer.

Here's how it works: Somebody buys a legitimate card and inserts it into a modified satellite receiver that will use the card to decrypt and reveal K which changes several times a day. How does the Sun make sure that only those, who paid for her beams will brown out?

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Related 9. Hot Network Questions. Question feed. One artifact is macroblocking, in which the fluid picture temporarily dissolves into blocks. Macroblocking is often mistakenly called pixilating, a technically incorrect term which has been accepted as slang for this annoying artifact.

Graphic artists and video editors use "pixilating" more accurately to refer to the distortion of an image. There really are pixels on your TV screen, but they're too small for your human eye to perceive them individually -- they're tiny squares of video data that make up the image you see. For more information about pixels and perception, see How TV Works.

The rate of compression depends on the nature of the programming. If the encoder is converting a newscast, it can use a lot more predicted frames because most of the scene stays the same from one frame to the next. In more fast-paced programming, things change very quickly from one frame to the next, so the encoder has to create more intraframes. As a result, a newscast generally compresses to a smaller size than something like a car race.

After the video is compressed, the provider encrypts it to keep people from accessing it for free. Encryption scrambles the digital data in such a way that it can only be decrypted converted back into usable data if the receiver has the correct decryption algorithm and security keys. Once the signal is compressed and encrypted, the broadcast center beams it directly to one of its satellites.

The satellite picks up the signal with an onboard dish, amplifies the signal and uses another dish to beam the signal back to Earth, where viewers can pick it up. When is pixilation not just an adverse effect of decoding? TLS 1. SSL inspection is useful when a business wants to know what its employees are sending outside of the organization, in addition to discovering malware in encrypted traffic and preventing hackers from getting past your security engines.

In the past six months of , 1. However, because web pages are not static, this can be dangerous. They are presented with tailored material that may include hundreds of things gathered from various sources. Regardless of the source, each object offers a potential threat and should be treated with caution. Malware creators, on the other hand, use encryption to conceal their exploits.

Allowing encrypted traffic to pass unnoticed exposes you to an increasing number of possible dangers. So, why would anyone want to let encrypted traffic pass via inspection engines?