Subject: [AAA-WG]: Issue: Inconsistencies between the base and transport drafts

From: Jonathan Wood <[email-masked]>
Date: Wed, 21 Nov 2001 14:31:32 -0800 (PST)

Submitter name: Jonathan Wood
Submitter email address: [email-masked]
Date first submitted: 21-Nov-01
Reference:
Document: base
Comment type: E
Priority: 1
Section: Base (version 8 alpha2), sections 5.6, 5.6.2, and 12
Rationale/Explanation of issue:

The transport draft and the base spec are in conflict about
sending watchdogs. The state machine in the base spec section 5.6
requires that watchdogs be sent on each expiration of the watchdog
timer. However, the transport draft requires that a watchdog be
send once on the first expiration of the watchdog timer. On the
next expiration of the watchdog timer, the connection is put in
the suspect state, and the connection is failed over.

Also, section 5.6 states

   When the state machine below requests a
   transport connection with the peer, the state machine in [52] is
   invoked. Once the connection has been established, the state machine
   in this section is followed.

This is not completely accurate. The state machine in the transport
draft should be followed throughout the life of the connection as
well to manage the connection.

There are also some leftover timer descriptions in section 12 that
are no longer relevant.

Requested change:

I recommend that text specifying how to control sending watchdogs and
management of the watchdog timer be stricken from the base spec, and
that the base spec refer to the transport draft on this matter.

Specifically:

5.6  Peer State Machine
(Modify 2nd paragraph)

   This state machine is closely coupled with the state machine
   described in [52], which is used to open, close, failover, probe,
   and reopen transport connections. Note in particular that [52]
   requires the use of watchdog messages to probe connections. For
   Diameter, DWR and DWA messages are to be used.

Remove from R-Open:

                       WatchDog-Timer   R-Snd-DWR        R-Open

Remove from I-Open:

                       WatchDog-Timer   I-Snd-DWR        I-Open

Remove from section 5.6.2  Events:

      WatchDog-Timer The Watchdog timer expired, indicating that a DWR
                     message is to be sent to the peer.

      Rcv-DWR        A DWR message was received.

      Rcv-DWA        A DWA message was received.

Section 12.0  Diameter protocol related configurable parameters

Recommend removing the following timers:

      Td timer
         The Td timer controls the termination of connections with peer
         in the SUSPECT state. The recommended value is 5 seconds.

      Ti timer
         The Ti timer controls the frequency the watchdog messages are
         to be sent to idle peers. The recommended value is 30 seconds.

      Tr timer
         The Tr timer controls the frequency the watchdog messages are
         to be sent to peers when there are pending requests, but not
         messages have been received from the peer. The recommended
         value is 10 seconds.

      Tw timer
         The Tw timer controls the changing of a peer to the SUSPECT
         state when no answer is received to a watchdog request. The
         recommended value is 5 seconds.

What about the Tc timer?