SSL Encryption

Did you generate your key on the LTM? If so, you just need to import the certificate you purchased under Local Traffic->SSL Certificate List -> Import. If not, then you'll need to import both key & certificate (same location). Once that is in place, you'll need to create a clientssl profile that references your certificate. You can specify the cipher to be only AES256-SHA in the ssl profile ciphers section, but it's atypical to limit clients to just one, you might prevent some clients from connecting. Of course, if it's a security requirement for that particular application, then the clients will be knowledgeable on this I suppose, or at least the administrators of those clients will be.