[Iccrg] Re: Testing ECN support for UDP flows

[ken carlberg]

Ingemar,

This particular response may be best for the ICCRG list and its  
research view of things, but would it be possible to accomplish some  
of what you want to do directly or indirectly through PlanetLab?  I  
don't recall the connectivity requirements and layout for PlanetLab,  
but to avoid ECN info lost from encapsulated traffic between PlanetLab  
sites, perhaps one could find multi-homed hosts that can also be  
reached via the Internet.  And since the hosts are targeted for  
research work, one should be able to add some of the test software you  
are speaking of below.  (but this is just an educated guess on my part)

-ken


On Aug 20, 2009, at 7:43 AM, Ingemar Johansson S wrote:

> Hi
>
> Sorry for the cross-post, I would believe that it is best to reply  
> to tsv-area only.
>
> I have previously asked people regarding the support of ECN  
> especially for UDP flows.. There seems to be a lot of uncertanities  
> around this and in general it is difficult to get any clear view (if  
> there is any ?)
> So... how do I best test this on a larger scale ?
>
> 1) UDP port 7: The idea is to ping other host with UDP packets on  
> port 7, some of the packets are ECT(0)/(1) marked, some are not. If  
> I get things right, port 7 is not genarally enabled these days, are  
> there any host around that are known to leave port 7 open.
>
> 2) Modified STUN client: The idea is to do STUN requests to a number  
> of STUN servers. Some of the STUN requests are ECT.
>
> 3) Setup a mesh of volountary hosts that installs a software that  
> agrees to communicate via a specific port, the hack would need to  
> implement some means to communicate NAT'ed addresses etc. This would  
> require some logistic effort to gather up volounteers for the test- 
> fest.
>
> Ideally the test should be able to tell if possible ECN issues are  
> located close to the user (e.g firewalls, WLAN routers etc) or in  
> the core-networks. Also I believe that running UDP would be  
> beneficial even though I know some people have already tried with  
> ICMP.
>
> Which would be the best alternative in order to do such a test ?,  
> comments/suggestions are welcome.
>
> Regards
> Ingemar
>
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> Ingemar Johansson
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> EAB/TVK - Multimedia Technologies
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