One of our customers requires us to encrypt a message return from our web service using AES 256 & Public Key Encryption Server Side (web service) is java based. Client side could be java or .Net.
I'm not familiar with any of the encryption methodology and could not find any example that will get me started...
Can this even be implemented AES 256 & Public Key Encryption ?
How does it work (Public Key Encryption) ?
Please direct me to an example that will get me started.
AES256 is a specific symmetric encryption scheme, which requires the communicating parties to have pre-shared an encryption key. Public-key cryptography on the other hand is an asymmetric encryption principle, where each communicating party has a public key shared with every one and a private key which he keeps a secret. A typical example for the latter would be RSA.
Both symmetric and asymmetric encryption have there pros and cons, you should first figure out what you (or your client) want. Then, when implementing any cryptography always be sure to use common libraries and never (ever) try to implement any cryptography algorithms yourself. Small mistakes in these topics often lead to complete insecurity.
来源：https://stackoverflow.com/questions/16812938/java-aes-256-public-key-encryption