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Re: [EFM]Event Time Stamp





Here's my recollection of the justification of timestamping...

The timestamp is not intended to represent the time since system uptime.  At least not for any piece of reliable equipment:)  It was added to provide "relative" times between events for more accuracat reporting (e.g. if source timestamps X & Y as happening 500 ms apart, thats probably more accurate than the receiver getting them 650ms apart due to the delay caused by the limited number of OAM frames).  The origin of the utility can be found in 

http://www.ieee802.org/3/efm/public/mar03/oam/gerhardt_oam_1_0303.pdf.

- Matt

On Mon, 4 Aug 2003 16:38:59 -0400, Yonghong Ren <ren@appiancom.com> wrote:

> The most recent draft (2D) defines the Event Time Stamp in Event TLV as
> 16-bit, in the unit of 100ms. If we assume this "time reference" to mean
> something like a system uptime, then it's simply not wide enough.
> Interestingly, the Event Time Stamp references section 30.11.1.1.37-40,
> where the time stamps seem to be defined as 32-bit integers. So, perhaps
> it's simply a typographical error?
> I would appreciate any clarification for me. Thanks.
> -- Yonghong Ren
>