Hi,
I am currently trying to write a program in Java using ECC. I have created a secret key which is shared between two clients. I am now trying to encrypt/decrypt a message using this secret key. I was going to use ECIES, however it only recognises the public and private keys (not the secret key). Does anyone have any ideas how i can encrypt/decrypt a message?

Thanks in advance

I think you might have your wires crossed a bit, EC is an asymmetric algorithm, not a symmetric one. You might want to have another look at Chapter 4. It shows various uses of EC plus examples.

Regards,

David

After reading your comment I did a bit more research on the topic, and found that you can combine an asymmetric algorithm, like ECC, with a symmetric algorithm, like AES. So what I want to do is use the ECC secret key with the AES encryption, however I can not figure out how to do this. Does anyone know how to change the format of the ECC Secret key so that it can be use with AES?
Thanks again

Combining symmetric key usage with ECC requires the use of Key Agreement. This is covered in Chapter 4, on pages 110 to 112, which shows a basic agreement strategy. If you need a strategy that requires reuse of the EC keys you need to look at methods based on X9.63.

Regards,

David