[OpenSIPS-Users] [presence] timer for waiting or pending states in winfo

Iñaki Baz Castillo ibc at aliax.net
Mon Jun 15 01:40:47 CEST 2009


Hi, how does OpenSIPS implement the timers for "pending" and "waiting" status 
in Subscription State Machine (RFC 3857 Section 4.7.1):

   Of course, policy may never be specified for the subscription.  As a
   result, the server can generate a giveup event to move the waiting
   subscription to the terminated state.  The amount of time to wait
   before issuing a giveup event is system dependent.

   The giveup event is generated in either the waiting or pending states
   to destroy resources associated with unauthorized subscriptions.
   This event is generated when a giveup timer fires. This timer is set
   to a timeout value when entering either the pending or waiting
   states.  Servers need to exercise care in selecting this value.  It
   needs to be large in order to provide a useful user experience; a
   user should be able to log in days later and see that someone tried
   to subscribe to them.  However, allocating state to unauthorized
   subscriptions can be used as a source of DoS attacks.  Therefore, it
   is RECOMMENDED that servers that retain state for unauthorized
   subscriptions add policies which prohibit a particular subscriber
   from having more than some number of pending or waiting
   subscriptions.


This is, A subscribes to B whie B is not registered. B becomes registered 
after 2 days and subscribes to its own watcher information. Would B receive 
the notification about the subscribe attemp from A to B?

Thanks.

-- 
Iñaki Baz Castillo <ibc at aliax.net>



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