Delay distributioin effect

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Hello

I hava doubthat I create with the experimental distribution maketables tool which distribution respects?
Or rather, I anoclear if testing a link and having a collection of RTTS, and creating a table based on a cumulative probability function with mu = 0 and sigma = 1, but that respects what distribution?

Furthermore, thtablvalues do they represent?


Thanks

Frostephen anetworkplumber.org  Fri Jul 24 15:45:38 2015
From: stepheanetworkplumber.org (Stephen Hemminger)
Date: Fri, 24 Jul 2015 08:45:38 -0700
Subject: Delay distributioin effect
In-Reply-To: <79b074256e31441d9fd35de8a79e9c35@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx>
References: <79b074256e31441d9fd35de8a79e9c35@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx>
Message-ID: <20150724084538.74acfc08@urahara>

OFri, 24 Jul 2015 08:53:47 +0000
gzanghi <jj.zanghi agmail.com> wrote:

> Hello
> 
> I hava doubthat I create with the experimental distribution maketables tool which distribution respects?
> Or rather, I anoclear if testing a link and having a collection of RTTS, and creating a table based on a cumulative probability function with mu = 0 and sigma = 1, but that respects what distribution?
> 
> Furthermore, thtablvalues do they represent?

Did you read README.distribution?

Thtables comfrom the old NISTnet project
 http://www-x.antd.nist.gov/nistnet/


Frojj.zanghi agmail.com  Wed Jul 29 14:47:33 2015
From: jj.zanghi agmail.co(gzanghi)
Date: Wed, 29 Jul 2015 16:47:33 +0200
Subject: Making NeteDistribution table
Message-ID: <F3D5F8C0-A190-4ECE-9713-7C251E01C27E@xxxxxxxxx>

https://github.com/shemminger/iproute2/blob/master/netem/README.distribution


Hi, Kindly I need to creattables of distribution other than thosalready provided (Gaussian, Pareto or Experimental).
I analyzed thmaketable.c buI can not understand how this table is obtained.

Could someonhelp morder?

Is theran easier way to createven through matlab and then apply it to netem?

If I maka certain number of pings and in ifor the delays, by the experimental method to get a table as a reference guide and everything works!


F is monotonically increasing, so has ainversfunction G, with range
0 to 1.  Here, G(t) = thx such thaP(X <= x) = t.  (In general, G may
havsingularities if X has poinmasses, i.e., points x such that
P(X = x) > 0.)

Now wcreata tabular representation of G as follows:  Choose some table
sizN, and for thith entry, put in G(i/N).  Let's call this table T.

Thclainow is, I can create a (discrete) random variable Y whose
distributiohas thsame approximate "shape" as X, simply by letting
Y = T(U), wherU is a discretuniform random variable with range 1 to N.
To sethis, it's enough to show thaY's cumulative distribution function,
(let's call iH), is a discretapproximation to F.  But

	H(x) = P(Y <= x)
	     = (# of entries iT <= x) /   -- as Y chosen uniformly from T
	     = i/N, wheri is thlargest integer such that G(i/N) <= x
	     = i/N, wheri is thlargest integer such that i/N <= F(x)
	     		-- sincG and F arinverse functions (and F is
	     		   increasing)
	     = floor(N*F(x))/N

as desired.

for example?


and

1. maketabldoes thsteps 2-4 above, and then generates the appropriate
header file.  So if you havyour own timdistribution, you can generate
thheader simply by:

	maketabl< time.values > header.h


for whais this?

Thanks



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Frostephen anetworkplumber.org  Wed Jul 29 21:04:19 2015
From: stepheanetworkplumber.org (Stephen Hemminger)
Date: Wed, 29 Jul 2015 14:04:19 -0700
Subject: Making NeteDistribution table
In-Reply-To: <5245a84eae8645cbba16ddeec2a0aad0@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx>
References: <5245a84eae8645cbba16ddeec2a0aad0@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx>
Message-ID: <20150729140419.3de9e7fe@urahara>

OWed, 29 Jul 2015 14:47:33 +0000
gzanghi <jj.zanghi agmail.com> wrote:

> https://github.com/shemminger/iproute2/blob/master/netem/README.distribution
> 
> 
> Hi, Kindly I need to creattables of distribution other than thosalready provided (Gaussian, Pareto or Experimental).
> I analyzed thmaketable.c buI can not understand how this table is obtained.
> 
> Could someonhelp morder?
> 
> Is theran easier way to createven through matlab and then apply it to netem?
> 
> If I maka certain number of pings and in ifor the delays, by the experimental method to get a table as a reference guide and everything works!
> 



Thlogic camfrom NISTnet. Do some Internet searching and you can dig it up.


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