Subject: [BEHAVE] TURN Issue: Recommended Permission Lifetime

From: Philip Matthews <[email-masked]>
Date: Tue, 15 Jan 2008 17:00:18 -0500

TURN-05 recommends a permission lifetime of 60 seconds:

    o  checks if a timer has been set for this permission.  If none has
       been started, the server starts one.  It is RECOMMENDED that it
       have a value of sixty seconds.  If the timer is already running,
       it MUST be reset.

However the BEHAVE-UDP specification (RFC 4787) recommends a much  
longer lifetime for the similar UDP mapping timer:

    REQ-5:  A NAT UDP mapping timer MUST NOT expire in less than two
       minutes, unless REQ-5a applies.

       a) For specific destination ports in the well-known port range
          (ports 0-1023), a NAT MAY have shorter UDP mapping timers that
          are specific to the IANA-registered application running over
          that specific destination port.

       b) The value of the NAT UDP mapping timer MAY be configurable.

       c) A default value of five minutes or more for the NAT UDP  
mapping
          timer is RECOMMENDED.

It seems to me that these two lifetimes should be consistent, and  
thus I propose to change the recommended TURN permission lifetime to  
be 5 minutes.

Comments?

- Philip

_______________________________________________
Behave mailing list
[email-masked]
https://www1.ietf.org/mailman/listinfo/behave

---

From: Cullen Jennings <[email-masked]>
Date: Wed, 16 Jan 2008 20:30:45 -0800

> thus I propose to change the recommended TURN permission lifetime to  

I agree - I think 5 min RECOMMENDED and MUST NOT be less than 2  
minutes would be good.

---

From: Philip Matthews <[email-masked]>
Date: Fri, 18 Jan 2008 12:13:47 -0500

> I agree - I think 5 min RECOMMENDED and MUST NOT be less than 2  

I agree. So unless I hear any objections soon, this is what TURN-06  
will say.

- Philip

---

From: "Dan Wing" <[email-masked]>
Date: Fri, 18 Jan 2008 12:53:22 -0800

> I agree. So unless I hear any objections soon, this is what TURN-06  

There is a signaling protocol (TURN).  Why not have the TURN
server indicate its default if it is anything other than 5
minutes.

-d

---

From: Jonathan Rosenberg <[email-masked]>
Date: Mon, 21 Jan 2008 00:06:28 -0500

I think we agreed to not handle signaling of permission lifetimes, since 
that capability doesn't exist for NAT either. If SAFE happens and we get 
a mechanism then we can use it for turn too.

-Jonathan R.

-- 
Jonathan D. Rosenberg, Ph.D.                   499 Thornall St.
Cisco Fellow                                   Edison, NJ 08837
Cisco, Voice Technology Group
[email-masked]
http://www.jdrosen.net                         PHONE: (408) 902-3084
http://www.cisco.com