hi...we are a group of students working on a public-key encryption project using rsa-oaep scheme.we are using redhat linux 9 as our os-platform and c as the back-end programming language.the problem is that we need integers greater than 2^64(say 2^512 or 2^1024 etc.) for working...crossing way beyond the maximum limit of the c-compiler.how do we overcome the problem?

Try useing the GMP library located here : http://www.swox.com/gmp/

Take a look at the Integer Functions , Initializing Integers and Assigning Integers .

Hope this will help you and your project.

Regards,
DG.