Published on Dec 12, 2016
A Java Card is a smart card that is capable of running Java programs. The Java Card 2.0 specification contains detailed information for building the Java Card virtual machine and application programming interface (API) in smart cards. The minimum system requirement is 16 kilobytes of read-only memory (ROM), 8 kilobytes of EEPROM, and 256 bytes of random access memory (RAM). A Java Card is shown below.
Description of Java Card
Java Card is a smart card that is capable of running programs written in Java. For this a new Java platform, Sun's JavaSoft division has made available the Java Card 2.0 API specification, and several licensees are now implementing this API on smart cards. In order to program Java Cards that are 2.0-compliant, developers need to understand what a Java Card is architecturally, what its core classes are, and how to develop applications for the card. This article gets inside a Java Card, providing you, the developer, with technical guidance on the system architecture, application programming interface, and runtime environment of the Java platform in a smart card.
Types of smart cards
There are two basic kinds of smart cards:
1. Intelligent smart card
An intelligent smart card contains a microprocessor and offers read, write, and calculating capability, like a small microcomputer.
A memory card, on the other hand, does not have a microprocessor and is meant only for information storage. A memory card uses security logic to control the access of memory.
The lifetime of a Java Card
The Java Card lifetime starts when the native OS, Java Card VM, API classes libraries and optionally, applets are burned into ROM. This process of writing the permanent components into the non-mutable memory of a chip for carrying out incoming commands is called masking.
Before it lands in your wallet, a Java Card needs to go through initialization and personalization. Initialization refers to loading general data into a card's non-volatile memory. This data is identical across a large number of cards and is not specific to an individual; an example might be the issuer or manufacture's name.
The next step, personalization, involves assigning a card to a person. It can occur through physical personalization or through electronic personalization. Physical personalization refers to embossing or laser engraving your name and card number on the plastic surface of a card. Electronic personalization refers to loading personal data into a card's non-volatile memory, for example, your personal key, name, and pin number. Initialization and Personalization vary from vendor to vendor and issuer to issuer. In both, EEPROM (a type of non-volatile memory) is often used for storing data.