Re: [P2PSIP] time synchronization?

Roland Bless <roland.bless@kit.edu> Tue, 27 August 2013 09:44 UTC

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Date: Tue, 27 Aug 2013 11:44:17 +0200
From: Roland Bless <roland.bless@kit.edu>
Organization: Institute of Telematics, Karlsruhe Institute of Technology (KIT)
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To: "Songhaibin (A)" <haibin.song@huawei.com>
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Subject: Re: [P2PSIP] time synchronization?
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Hi,

On 14.08.2013 03:31, Songhaibin (A) wrote:
> In –diagnostics draft, we have timestamp that is used by the
> intermediate nodes to check if the message is expired or not. It raises
> a problem of time synchronization. I think we need a decision from the
> WG. We need careful consideration on how to use the timestamp because
> time synchronization is a barrier in open Internet environment, while in
> a managed environment, it may be less of a problem. Do we want to
> enforce the time synchronization or do we want to lose the feature to
> check the message expiration (and one-way-delay)? Please tell what you
> are thinking about.

As the base (RELOAD) draft doesn't require any time synchronization
mechanism, I think, it's not useful to enforce the use of
time synchronization in any other draft. IMHO it's obvious
that you may have advantages if time synch is available;
more important is how you could distinguish from the protocol
if it's used or not.

Regards,
 Roland