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About System.Security.Cryptography.Pkcs 

System.Security.Cryptography.Pkcs is the namespace that contains the managed code implementation of the Cryptographic Message Syntax (CMS) and Public-Key Cryptography Standards #7 (PKCS #7) standards. CMS is a superset of PKCS #7. This documentation refers to the Microsoft implementation of this combination of technologies as CMS/PKCS #7 to emphasize that there are dual standards implemented in this namespace.

For more information about CMS, see Cryptographic Message Syntax (CMS) (

For more information about PKCS #7, see PKCS #7: Cryptographic Message Syntax Standard (

In This Section

The following topics provide information about managed CMS/PKCS #7.

Security Services Provided by CMS/PKCS #7

Provides the ability to implement several security services into an application.

Algorithm Support in CMS/PKCS #7

Supports many cryptographic algorithms.

Components of a CMS/PKCS #7 Message

Facilitates the implementation of multiple security services into a message. Attributes can also be associated with the CMS/PKCS #7 message, which yield additional information about the message.

Types of CMS/PKCS #7 Messages

Provides implementations of several protected message types.