+@cindex REQ_KEY
+@cindex ANS_KEY
+@cindex KEY_CHANGED
+@example
+message
+------------------------------------------------------------------
+REQ_KEY origin destination
+ | +--> name of the tinc daemon it wants the key from
+ +----------> name of the daemon that wants the key
+
+ANS_KEY origin destination 4ae0b0a82d6e0078 91 64 4
+ | | \______________/ | | +--> MAC length
+ | | | | +-----> digest algorithm
+ | | | +--------> cipher algorithm
+ | | +--> 128 bits key
+ | +--> name of the daemon that wants the key
+ +----------> name of the daemon that uses this key
+
+KEY_CHANGED origin
+ +--> daemon that has changed it's packet key
+--------------------------------------------------------------------------
+@end example
+