What Is Simulcrypt Multicrypt And Difference between Simulcrypt Multicrypt



When the things comes in terms of CA System then two major terms which comes in mind. These two terms are Simulcrypt and Multicrypt. These two are different strategies of passing CAS in network.

Simulcrypt Multicrypt are the two terms whIch defines weather a network is using one CAS or multiple CAS sytem.

What Is Simulcrypt

If a network is encrypting content by one key shared by two different CA System (using 2 ECMs) is known as Simulcrypt.

In other words,

When we are using in our network more than one CAS simultaneously then it can be defined as simulcrypt. Simulcrypt is also known as Dual CAS Strategy.


As shown above in the figure a single service provider is using two different CAS known as CAS 1 and CAS 2.  These two cas are generating two different ECMs as ECM 1 and ECM 2. These two ECMs are going into the scrambler.

The scrambler will scramble MPEG Transport Stream where this MPEG Transport Stream is using multiple CAS.  The scrambler is giving output as 100% encrypted stream.

Now this signal is going into the two different IRDs or STBs where each IRD is dedicated to use one CAS only.  So the IRDs which  support CAS 1 will decrypt the content using ECM 1 key and the IRDs which support the CAS 2 will decrypt the content using ECM 2 key.

Thus these IRDs  are made to use one CAS only. In these IRDs smart card is not physically available. Subscriber can not change the smart card. It uses the in built smart card. That is why this is called dedicated IRDs.

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What Is Multicrypt

In the Multicrypt system each service provider use only one CAS System.


As shown above in the figure service provider 1 using his CAS 1 while other service provider is using different cas  named as CAS 2.  In Multicrypt system the stream is 100% encrypted with one CA system only.

In this system the IRD which we use have smart card physically available. If the subscriber want to change the smart card then he can change it easily because smart card slot is available there.

Multicrypt enable users to switch between two different service providers easily. European IRDs have single or multiple PCMCIA security elements.

Above shown in the figure “CAS 1 & CAS 2 IRD” means it support both CAS system and one at a time.

Conclusion Simulcrypt Multicrypt

Thus we found that Simulcrypt Multicrypt are two different strategies of implementing CAS in network. In Simulcrypt the IRDs which we use have less cost than the IRDs we use in Multicrypt. Multicrypt is mandatory in spain. Simulcrypt is mainly used in Europe.

Multicrypt makes easy to subscribers to switch between two different service providers while in Simulcrypt system you need to change the IRD of subscriber. This is all about Simulcrypt Multicrypt.

Know More About      What Is ECM EMM In CA System

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  1. KAMAL BERA says:

    more update for digital headend cable distribution system please sir

  2. Tarun says:

    what is the reason of absence of card in case of simulcrypt?


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