The spec. is not too long; it probably worth reading it (the first four 
paragraphs). Matching on sequence numbers is not possible without coding. With 
coding everything is possible.
In your case I think you'd even need matching (and wildcarding) on bits of the 
sequence number, unless you want to install 2^32 entries per flow.

I think, for protoyping, it should be fairly easy to fork the switch code, and 
make your own group type for that purpose. Just copy-paste the current select 
group implementation, and add extend it with your own code. Group numbers 
128-255 are reserved for experimenter groups, so you can use those without any 
problem.


________________________________
From: Alexey Bogaevskiy [mailto:[email protected]]
Sent: Tuesday, August 16, 2011 5:33 PM
To: Zoltán Lajos Kis
Cc: Rob Sherwood; Opeflow Mailing List
Subject: Re: [openflow-discuss] Splitting a flow

What about sequence numbers of TCP packets, is it possible to have a rule based 
on that field ?

2011/8/16 Zoltán Lajos Kis 
<[email protected]<mailto:[email protected]>>
Well, this is also somewhat theoretical (as it has not been tested yet :o)), 
but in [1] I implemented select groups as a weighted round-robin of the 
buckets, without any hashing (around [2]). Anyway, if anyone is interested in 
using this feature, I'll promise to fix any problems that might arise.

Regards,
Zoltan.

[1] https://github.com/TrafficLab/of11softswitch
[2] 
https://github.com/TrafficLab/of11softswitch/blob/master/udatapath/group_entry.c#L413



> -----Original Message-----
> From: 
> [email protected]<mailto:[email protected]>
> [mailto:[email protected]<mailto:[email protected]>]
>  On
> Behalf Of Rob Sherwood
> Sent: Tuesday, August 16, 2011 5:15 PM
> To: Opeflow Mailing List
> Subject: [openflow-discuss] Splitting a flow
>
> On Tue, Aug 16, 2011 at 8:00 AM, Ben Pfaff 
> <[email protected]<mailto:[email protected]>> wrote:
> >
> > OpenFlow 1.0 doesn't support this behavior.  I can't say
> for OpenFlow
> > 1.1, but I doubt it.
>
> [expanding a bit on what Zoltan just said]
>
> In theory, OpenFlow 1.1 has support for multi-path routing,
> where a single flow entry can be hashed across multiple
> ports, such that the flow is divided among the ports.
>
> The expected use case for this would be taking a flow entry
> that aggregated multiple tcp flows (e.g., "all traffic dst to
> 192.168.1.0/24<http://192.168.1.0/24>") and using, for example, a hash on the
> packet's five tupple (src and dst ip + src and dst l4 port +
> ip protocol) to map individual tcp flows to a port, so
> depending on what you mean by "flow", this use case might be
> what you're asking.  The other side of it is that openflow
> 1.1 does not define the hash function used, so in theory you
> could use this mechanism to map packets from the same tcp
> flow went out different ports.
>
> Unfortunately, all this is theoretical as I have not seen an deployed
> 1.1 implementations or implementations that implement this feature.
> If others know of some, I (as would this list :-) would be
> very interested in knowing about them.
>
> Hope that helps,
>
> - Rob
> .
> _______________________________________________
> openflow-discuss mailing list
> [email protected]<mailto:[email protected]>
> https://mailman.stanford.edu/mailman/listinfo/openflow-discuss
>
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