Abstract: Systems and techniques are described for optimizing secure communications. A client can use an authentication protocol, e.g., Kerberos, to authenticate with the server. Specifically, the client can obtain a service ticket from a ticket granting server, and then use the service ticket to authenticate with the server. The server can respond by providing an encrypted session key. The session key can then be used by the client and server to securely communicate with each other. A wide area network (WAN) optimization device described in this disclosure is capable of obtaining the session key without decrypting the service ticket. Specifically, the WAN optimization device can use information other than the service ticket to obtain the session key.