RMI is specification or implementation?

I'm a bit confused about RMI. The SDK comes with an implementation of RMI which I believe uses sockets. But are there other implementations of RMI, such as over https ?

thanks, D.

While exporting Remote objects (UnicastRemoteObject.exportObject()) you can specify a custom client and server socket factories.
I am not aware of any providers of the same.

That doesn't quite answer my question. If I rephrase,

Is it possible to do RMI over http?

thanks, D.

RMI can be used over various transports, JRMP and IIOP being the most common ones. These articles suggest that HTTP can also be used, but that it may not be all that obvious how to set it up.

RMI over http is nonsensical. RMI is a protocol. http is a protocol. http provides nothing RMI does not already have so that makes no sense.

You can do RMI with SSL however.

Tunnelling RMI over some other protocol may very well make sense. Getting through firewalls that only open port 80 is a typical application.