[e2e] Delivery times in mobile networs? Re: Are there any persons interested in TCP over mobile wireless networks in Germany?

[Lachlan Andrew]

Greetings Detlef,

Of course you can use an EWMA filter to estimate a non-stationary
process.  Why do you think you couldn't?

In a non-stationary process, such as fading, there is usually
considerable temporal correlation.  If the time constant of the filter
is short compared with the "body" of the autocorrelation of the
delivery times, then the non-stationarity makes essentially no
difference.

If you want to be taken seriously (as I know you do) then it would be
wise to tone down your criticism of other people's work.  Although it
is common for "standard practice" to be wrong, it is even more common
for it to be sensible.

Cheers,
Lachlan

On 13 December 2012 02:38, Detlef Bosau <detlef.bosau at web.de> wrote:
> Am 11.12.2012 14:20, schrieb Detlef Bosau:
>>
>> I have to apologize for this question, however, I would greatly appreciate
>> to get in touch with academic persons who are interested in this area.
>>
> My central question at the moment is: Do we have stationary packet delivery
> times on mobile wireless links?
>
> I was pointed to some papers, where those delivery times are estimated with
> EWMA filters.
> May I be honest? I absolutely hate academic lying. When a delivery time is
> not stationary, I cannot estimate it using an EWMA filter.
> (For EWMA filter fans: If you simply use "15" as the result for your EWMA
> filter, you have much less work and the result is as wrong as the original
> ;-))
>
> To my understanding, it simply is not reasonable to expect stationary
> delivery times here. But I'm trying to get a sound answer for this question
> for about a year now, and I don't find sound literature nor do I find
> someone to answer my question.
>
> Perhaps, this list is not the right place for my question, I would
> appreciate hints. However, I would like to find an answer to my question.
>
> Detlef
>
> --
> ------------------------------------------------------------------
> Detlef Bosau
> Galileistraße 30
> 70565 Stuttgart                            Tel.:   +49 711 5208031
>                                            mobile: +49 172 6819937
>                                            skype:     detlef.bosau
>                                            ICQ:          566129673
> detlef.bosau at web.de                     http://www.detlef-bosau.de
> ------------------------------------------------------------------
>



-- 
Lachlan Andrew  Centre for Advanced Internet Architectures (CAIA)
Swinburne University of Technology, Melbourne, Australia
<http://caia.swin.edu.au/cv/landrew>
Ph +61 3 9214 4837