Bytecode verification on Java smart cards

This article presents a novel approach to the problem of bytecode verification for Java Card applets. By relying on prior off-card bytecode transformations, we simplify the bytecode verifier and reduce its memory requirements to the point where it can be embedded on a smart card, thus increasing significantly the security of post-issuance downloading of applets on Java Cards. This article describes the on-card verification algorithm and the off-card code transformations, and evaluates experimentally their impact on applet code size.