I'm wondering if there's a way to use grpc-java on Java Card applets. Based on the Java Card documentation, network protocols such as TCP, TLS, HTTP and HTTPS are supported, on the other hand Java Card runtime is very limited compared to JVM and works in a memory constrained environment. I'd appreciate any information or poc or thoughts about this, thx.
Probably not. although oracle defined the Java Card connected edition it is very uncommon and rarely seen in the wild, almost all implementations of java card operating systems are running Java Card classic edition. The usual way would be to rewrite a library using an abstract crypto interface that can be plugged to using a Smartcard, like pkcs11, minidrivers or something proprietary running crypto primitives on java Card but doing the network protocol stack on the host machine