The OF 1.3 specification says the following on the body of a flow stats reply (p. 63.):
"The fields consist of those provided in the flow_mod that created the flow entry..." So in my reading whatever was sent by the controller should be sent back unmodified by the switch upon stats query, which is a). Regards, Zoltan. -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Christian Esteve Rothenberg Sent: Tuesday, October 02, 2012 4:47 PM To: Eder Leão Fernandes Cc: [email protected] Subject: Re: [openflow-discuss] How masked values are stored in the Flow Table on OpenFlow 1.2? Hi all, just looking for further clarification on the issue of how to handle OXM wildcarded flow entries. If the controller sends a flow mod command that includes a flow match as follows: IP 192.168.1.1 IP_mask= 255.255.0.0 How should the flow entry installed by the switch look like? a) IP 192.168.1.1 IP_mask= 255.255.0.0 or b) IP 192.168.0.0 IP_mask= 255.255.0.0 ? While for actual packet matching purposes it does not matter, it matters when you want to query about statitstics or when you want to modify flow entries, as the field and mask values needs to be syntatctically equal, not functionally equal (i.e. after applying the mask). Our interpretation is that the mask should not be applied by the switch when installing the entry and should be respect what was sent by the controller (a). However, we have encoutered 1.2 prototype implementations that seem to have opted for the second interpretation (b). That said, it seems like a good best practice that the controller itself applies any widlcards to the match field before sending any protocol message with an OXM flow match structure. -Christian On Fri, Sep 28, 2012 at 10:49 AM, Eder Leão Fernandes <[email protected]> wrote: > Hi, > > I have a question regarding how masked OXM values are stored in the > flow tables. I would like to know if the values should be stored with > the respective mask applied? > For example: > If I have an IP source value 192.168.16.150 and mask 0xffffff00. The > value should be stored as 192.168.16.150 or 192.168.16.0? > > I'm asking this because, when testing Ryu Controller with CPqD > implementation of OpenFlow 1.2 software switch, I noticed that tests > with masked fields expect values with the mask applied, leading to > failures, since the switch implementation doesn't stores the values > with the masks applied. > > Thanks in advance, > Eder. > > -- > > > _______________________________________________ > openflow-discuss mailing list > [email protected] > https://mailman.stanford.edu/mailman/listinfo/openflow-discuss > -- Christian _______________________________________________ openflow-discuss mailing list [email protected] https://mailman.stanford.edu/mailman/listinfo/openflow-discuss _______________________________________________ openflow-discuss mailing list [email protected] https://mailman.stanford.edu/mailman/listinfo/openflow-discuss
