java card

Java Card aims at defining a standard smart card computing environment allowing the same Java Card applet to run on different smart cards, much like a Java applet runs on different computers.

As in Java, this is accomplished using the combination of a virtual machine (the Java Card Virtual Machine), and a well-defined runtime library, which largely abstracts the applet from differences between smart cards.

Portability remains mitigated by issues of memory size, performance, and runtime support (e.g. for communication protocols or cryptographic algorithms).

Security

Java Card technology was originally developed for the purpose of securing sensitive information stored on smart cards.

Security is determined by various aspects of this technology: Data encapsulationData is stored within the application, and Java Card applications are executed in an isolated environment (the Java Card VM), separate from the underlying operating system and hardware.Applet FirewallUnlike other Java VMs, a Java Card VM usually manages several applications, each one controlling sensitive data.

Different applications are therefore separated from each other by an applet firewall which restricts and checks access of data elements of one applet to another.CryptographyCommonly used symmetric key algorithms like DES, Triple DES, AES, and asymmetric key algorithms such as RSA, elliptic curve cryptography are supported as well as other cryptographic services like signing, key generation and key exchange.AppletThe applet is a state machine which processes only incoming command requests and responds by sending data or response status words back to the interface device.