SAMs 2GSI

Datum: 15.01.2022 | Public Transport Information

What is a SAM?

A Secure Application Module (SAM) is usually a small chip that is used, for example, in sales or control terminals. 

SAMs are essential for (((eTicket Germany: The Secure Application Modules handle the security-related cryptographic functions within the ticketing components and form a central basis for the secure issuance and distribution of electronic tickets.

SAMs can be chips fitted into sales or validation terminals. However, there are also software-based SAMs. They are used wherever terminals communicate directly with a user medium, such as a chip card. 

What tasks does a SAM perform?

Among other things, a SAM performs security-critical functions in sales and validation terminals. These include, for example:

  • the generation and processing of cryptographic signatures
  • the authentication of user media
  • the protection of cryptographic keys
  • verifying transaction signatures in back-end systems

 

In this way, SAMs ensure that cryptographic operations are carried out correctly and that sensitive keys are protected.

What types of SAM are there?

 

Level 1 SAMs are intended for development, testing and component validation. They enable realistic testing under secure conditions.

All Level 1 SAMs are configured identically and contain the same data. Unlike with higher security levels, the keys they contain can be loaded outside the Trust Centre’s highly secure environment. The key values are therefore not confidential, which means that cryptographic calculations can be traced and verified even outside the SAM. This makes development and debugging in particular much easier.

Level 2 SAMs are used in production environments. They contain individual cryptographic keys and meet higher security requirements than Level 1 SAMs.

Level 3 SAMs represent the highest security level within the (((eTicket Deutschland architecture. They are intended for regular operational use and also contain individual keys that are managed exclusively within the Trust Centre’s highly secure infrastructure.

When developing new user media or terminals, it is advisable to start by using a Level 1 SAM. It offers the same functional features as a Level 3 SAM used later in live operation, but without utilising confidential cryptographic keys. Manufacturers of ticketing components can order these Level 1 SAMs via our ASM tool and use them to test their components under realistic conditions.

About the ASM tool