Java Card

Java Card refers to a software technology that allows Java-based applications (applets) to be run securely on smart cards and similar small memory footprint devices. Java Card is the tiniest of Java platforms targeted for embedded devices. Java Card gives the user the ability to program the devices and make them application specific. It is widely used in SIM cards (used in GSM mobile phones) and ATM cards. The first Java Card was introduced in 1996 by Schlumberger's card division which later merged with Gemplus to form Gemalto. Java Card products are based on the Java Card Platform specifications developed by Sun Microsystems (later a subsidiary of Oracle Corporation). Many Java card products also rely on the GlobalPlatform specifications for the secure management of applications on the card (download, installation, personalization, deletion).

The main design goals of the Java Card technology are portability and security.

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).

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:

At the language level, Java Card is a precise subset of Java: all language constructs of Java Card exist in Java and behave identically. This goes to the point that as part of a standard build cycle, a Java Card program is compiled into a Java class file by a Java compiler; the class file is post-processed by tools specific to the Java Card platform.

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