Re: [manet-dlep-rg] Latency

The radios I've worked with report latency as a "rolling average", in ms, for queueing time + transmission. The total amount of time used for the rolling average is left to the radio implementation. 

Yes, multi-hop mesh radios confuse the issue. Ideally, I'd like to see "END-TO-END queueing time + transmission time", but some approximation thereof might work. I would contend that it's the modem's job to do the approximating (e.g. the modem provides "latency", *not* "Here's a hop count, and some multiplier for that hop count, go knock your lights out…"

Regards,
Stan

On Nov 12, 2013, at 8:43 AM, "Taylor, Rick" <Rick.Taylor@cassidian.com> wrote:

> From my experience:
> 
> My test DLEP devices just make up a number (not very helpful)
> 
> The radios I have used that support DLEP-00 natively report a latency in ms.  What that really is I have no idea.  Again, not very useful.
> 
> I have my own DLEP proxy for some other radios, and I have just reported half of RTT on my control packets, which given I have jitter and back-off, again isn't very useful.
> 
> BUT, Having a latency metric, even if it is almost meaningless, is better than no metric at all.
> 
> I could suggest 100ms * hop-count works in mesh radios, as one of the simplest uses of latency is as an improved hopcount for split-horizoning in routing protocols.
> 
> It's amazing what one will try to use, even if the quality of the data is very poor!
> 
> Rick Taylor
> 
>> -----Original Message-----
>> From: manet-dlep-rg-bounces@ietf.org [mailto:manet-dlep-rg-
>> bounces@ietf.org] On Behalf Of Henning Rogge
>> Sent: 12 November 2013 13:23
>> To: Teco Boot
>> Cc: DLEP Research Group (manet-dlep-rg@ietf.org); Stan Ratliff
>> Subject: Re: [manet-dlep-rg] Latency
>> 
>> Yes, I heard this too in the MANET Meeting...
>> 
>> which made me wonder a bit because I was puzzled what was the
>> difference between the two.
>> 
>> Can maybe the people who already have an implementation for DLEP tell
>> us what kind of Latency they implemented?
>> 
>> Henning Rogge
>> 
>> On Mon, Nov 11, 2013 at 5:15 PM, Teco Boot <teco@inf-net.nl> wrote:
>>> 
>>> Op 11 nov. 2013, om 01:55 heeft Stan Ratliff (sratliff)
>> <sratliff@cisco.com> het volgende geschreven:
>>> 
>>>> Point 11 - I didn't hear that. Really, I didn't hear any conclusions
>> about Latency. Other opinions?
>>> 
>>> We discussed it and all speakers said it is an important metric, so it
>> will be an optional TLV in core document.
>>> 
>>> Wasn't Henning tasked with verifying Latency and EFT?
>>> 
>>> Teco
>>> 
>>> _______________________________________________
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>> 
>> 
>> 
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