This thread has some details:
http://studentbank.in/report-Java-Card--4125
JavaCardâ€From Hype to Reality
JavaCard has been one of the most hyped products in the smart card world. Java programmers can develop smart card code and also, such code could be downloaded to existing cards. A JavaCard is a typical smart card: it
conforms to all smart card standards and
thus requires no change to existing smart
card-aware applications.a Java Virtual Machine is implemented in its
read-only memory (ROM) mask. The JVM executes a Java
bytecode subset on the smart card, ultimately
providing the functions like signature, log-in, and
loyalty applications. Thus the JVM controls the access to all smart card
resources, such as memory and I/O, and
thus essentially serves as the smart cardâ„¢s
operating system.
Advantages:
-The new applications can be developed in portable Java.
-applications can be securely loaded to the card post-issuance.
JavaCard basics
JavaCard operates like a typical smart card. When the smart card reader sends a
command, the JavaCard processes it gives a response.
INTERNAL OPERATIONS:
The JVM boots up when a smart card terminal activates the hardware and returns the Answer. It then for commands from the smart card terminal.A command ,on its arrival, is decoded and either activates (selects a particular applet) or is forwarded to a previously selected applet.
IMPLEMENTATION:
JavaCard applets can be implemented using familiar Java development environments such as VisualCafe or Java Developerâ„¢s Kit.Such environments often offer a JavaCard simulator, which lets applet developers concentrate on application functionality and the correct API usage.after
compiling the appletâ„¢s code, a converter is
run on the Java class files preparing them
for download.
OPENPLATFORM ARCHITECTURE:
The OP security concept focuses on
the defined roles of the different software
providers for multiapplication cards:
-the cardâ„¢s OS provider
-the card issuer
-the card manufacturer
-the applet provider
JAVACARD ARCHITECTURE:
the cardâ„¢s ROM code
consists of memory access (RAM, ROM,
and EEPROM) and device drivers for the
I/O and sometimes the drivers for accessing the cryptocoprocessor. A significant part of the overall ROM
code already consists of JavaCard byte-code implementing the various APIs
defined in the JavaCard specification.
Full report:
http://zurich.ibmpdf/javacard.pdf