JSch

In the eventuality that you would like to use pure Java servers or WiredX and ensure that the sessions are secure, then it is imperious that you implement the SSH2 protocol for the X11 port forwarding. JSch is a tool that enables you to develop tools that include highly secure forwarding, file transfers and a secure TCP/IP connection.

Even though the application is written for Java, it is worth mentioning that it is dependent on JavaTM Cryptography Extension, which is known to work well with JSE 1.2.2, 1.3 and 1.4.0. Other noteworthy features include environmental variable passing, stream forwarding, remote exec, generating DSA and RSA key pairs, NONE Cipher switching and support for private keys in OpenSSL and PKCS#8 format.

The SSH protocol support is by far the most important feature of the tool and it ensures secure login, authentication, encryption and a safe compressed transmitted data. Unlike SSH1, SSH2 can overcome the patent issues regarding RSA, particularly when it expires. The latter protocol can fix some data integrity problems that SSH1 was known to have due to various technical reasons. Last, but not least important, the protocol is standardized with IETF Secure Shell working groups and you can easily find drafts available on the web.