Clarify that rend cookies shouldn't be reused

diff --git a/doc/spec/rend-spec.txt b/doc/spec/rend-spec.txt
index cab97097bc5ecae52cbea72f3d14d372aa67455f..d440c8a811dd6969ccf05411e57b5f76246477b2 100644 (file)
--- a/doc/spec/rend-spec.txt
+++ b/doc/spec/rend-spec.txt
@@ -591,7 +591,8 @@
         RC   Rendezvous cookie    [20 octets]
 
    The rendezvous cookie is an arbitrary 20-byte value, chosen randomly by
-   Alice's OP.
+   Alice's OP. Alice SHOULD choose a new rendezvous cookie for each new
+   connection attempt.
 
    Upon receiving a RELAY_COMMAND_ESTABLISH_RENDEZVOUS cell, the OR associates
    the RC with the circuit that sent it.  It replies to Alice with an empty