+The authentication protocol (see protocol.c for the up-to-date version) is:
+
+ Client Server
+ send_id(u)
+ send_challenge(R)
+ send_chal_reply(H)
+ send_id(u)
+ send_challenge(R)
+ send_chal_reply(H)
+ ---------------------------------------
+ Any negotations about the meta protocol
+ encryption go here(u).
+ ---------------------------------------
+ send_ack(u)
+ send_ack(u)
+ ---------------------------------------
+ Other requests(E)...
+
+ (u) Unencrypted,
+ (R) RSA,
+ (H) SHA1,
+ (E) Encrypted with symmetric cipher.
+