> > 1) When I send a FLOW_MOD with an Action to change de DL_VLAN, we talk > about SwitchFlowMap, which seems to come from the FlowSpaceUtil. Does > this mean that this SwitchFlowMap and the FlowEntries it talks about > are from the configured FlowSpace rules? >
Yes those are the ones. > 2) If the above is correct, about the entity FlowEntry, what does it > mean by "ActionList"? I'm confused because we only provide permissions > in the FlowSpace, not actions? Would this be a "hook" for adding a > future feature? The action list in FlowEntry is a little confusing sorry. That action list is actually used to store the persmissions a slice has on this flowspace entry. So for example, alice has write permissions and bob only has read permissions. Cheers. > > > Thanks again, I think I'm really getting somewhere! =) > > Victor T. > > On 11 September 2013 00:31, Ali Al-Shabibi <ali.al-shab...@stanford.edu> > wrote: >> Hi Victor, >> >> So what you are saying is correct. When a FlowMod arrives from a controller >> we know which slice/controller it's from. Therefore, the flowmod's match >> struct is matched against the flowspace of that slice. Then, for every >> flowspace rules matching the flowmod's match the original flowmod is >> expanded; ie. a new flowmod, which is the a composition of the original >> flowmod and the flowspace rule, is pushed to the switch. >> >> I don't if you found this page but it could help you understand how flowmods >> are handled -> >> https://github.com/OPENNETWORKINGLAB/flowvisor/wiki/FlowMod-Message >> >> Cheers. >> >> -- >> Ali >> >> On Sep 10, 2013, at 7:46 PM, Victor Torres <vit...@poli.ufrj.br> wrote: >> >>> Hello again Ali, >>> >>> Thank you for all you support so far. I think theres no way for me but >>> to go into FlowVisor's code. So, at first, I have a question and >>> appreciate any direction on how to go on with this: >>> >>> At first, I'm really interested in how FLOW_MOD messages are handled. >>> According to the FV Wiki >>> (https://github.com/OPENNETWORKINGLAB/flowvisor/wiki/IO-Overview), is >>> it correct to say that a FLOW_MOD message from a controller/slice will >>> pass through a SLICER that will match it against the flowspace, >>> rewrite it and push it to the switch? >>> >>> >>> Thanks again, >>> >>> Victor T. >>> >>> On 3 September 2013 13:45, Ali Al-Shabibi <ali.al-shab...@stanford.edu> >>> wrote: >>>>> 1) So FV does update its FlowTable Cache from OF Messages going Switch >>>>> <-> Controller. But when you say "at most every 30s, means that if it >>>>> doesn't get any update it asks the switch for its FlowTable? The FlowMod >>>>> thing means that the FlowVisor asks periodically for the switch for >>>>> modified flows? >>>>> >>>> >>>> So if no controller or user requests flowtable stats, FV does not store >>>> anything in its cache nor does it make any periodic requests. But if your >>>> controller asks for the flowtable then if it does not have a copy of the >>>> flowtable or if the cache is old, it will fetch the flowtable from the >>>> switch. Otherwise it will return the cached values. The reasoning behind >>>> this is: >>>> >>>> 1. There may be many controllers sitting on top of FV, therefore there may >>>> be many more flow table requests. >>>> 2. On some switch implementations, asking for the flowtable is an >>>> expensive operation (ie. forwarding may be delayed) >>>> >>>> For those two reasons, flowvisor caches the flowtable. Of course, you can >>>> change the refresh rate if you know your switches do not suffer from those >>>> issues. >>>> >>>> >>>>> 2) If a slice controller wants to install a flow that changes the VLAN >>>>> tag from A to B for a given flow, FV only approves it if the slice has >>>>> Read/Write permissions on flowspace with dl_vlan=A and dl_vlan=B? >>>> >>>> That's is correct. >>>> >>>>> If dl_vlan is wildcarded then everything is allowed, right? >>>> >>>> Yup that's right as well. >>>> >>>>> Finally, if its set to NONE it cannot install or mod flows that have (to >>>>> have) actions that change Vlan Tags? >>>>> >>>> >>>> And correct again ;) >>>> >>>> >>>>> >>>>> Sorry for asking so much but since these particular questions are very >>>>> important for our research I would lilke to understand it as accurately >>>>> as possible. >>>>> >>>> >>>> No worries, ask as many question as you can. >>>> >>>> >>>>> Thank you very much! >>>>> >>>>> Victor T. >>>>> >>>>> >>>>> >>>>> On 3 September 2013 13:04, Ali Al-Shabibi <ali.al-shab...@stanford.edu> >>>>> wrote: >>>>> Hi Victor, >>>>> >>>>>> 1) Does FlowVisor updates its FlowDB as OF Messages pass through it? Or >>>>>> does it asks directly the switches for their Flow Tables? Reading the >>>>>> source code I'm inclined to think of the first option. >>>>> >>>>> You are mostly right. Flowvisor stores a cache of the flowtable which it >>>>> refreshes at most every 30s (this is configurable in versions 1+ of FV). >>>>> One important note is that flowmods are not stored when they are pushed >>>>> down by a controller, but rather they are periodically read from the >>>>> datapath. >>>>> >>>>>> >>>>>> 2) I would like to be able to keep a certain controller from installing >>>>>> or modding Flows that change the VLAN Tag of a packet, for instance. Can >>>>>> you point out a direction to do this? I was investigating the source >>>>>> code, but I'm not sure if I should try to implement a new Callback type >>>>>> or something like that. >>>>> >>>>> FV will disallow a controller from pushing or modding a vlan tag if >>>>> either that vlan tag is not in the flowspace associated to that >>>>> controller or if dl_vlan is set to none. >>>>> >>>>>> >>>>>> If I get to any results I would gladly pull it in the future. >>>>>> >>>>> >>>>> That would be fantastic. Let me know if you need more help. >>>>> >>>>>> >>>>>> Big thanks! >>>>>> >>>>>> Victor T. >>>>>> >>>>>> >>>>>> On 30 August 2013 18:46, Ali Al-Shabibi <ali.al-shab...@stanford.edu> >>>>>> wrote: >>>>>> Hi Victor, >>>>>> >>>>>> Currently, you cannot specify which openflow actions are allowed on a >>>>>> per flowspace basis. This is clearly a desirable feature but >>>>>> unfortunately we have not addressed it yet. We would welcome any pull >>>>>> requests/contributions in this direction. >>>>>> >>>>>> Cheers. >>>>>> >>>>>> -- >>>>>> Ali >>>>>> >>>>>> On Aug 30, 2013, at 11:58 AM, Victor Torres <vit...@poli.ufrj.br> wrote: >>>>>> >>>>>>> Hello, >>>>>>> >>>>>>> Does anybody know if it is possible to define allowed/denied actions >>>>>>> for slices in FlowVisor? >>>>>>> >>>>>>> >>>>>>> Best regards, >>>>>>> >>>>>>> Victor T. >>>>>>> _______________________________________________ >>>>>>> openflow-discuss mailing list >>>>>>> openflow-discuss@lists.stanford.edu >>>>>>> https://mailman.stanford.edu/mailman/listinfo/openflow-discuss >>>>>> >>>>>> >>>>> >>>> >> _______________________________________________ openflow-discuss mailing list openflow-discuss@lists.stanford.edu https://mailman.stanford.edu/mailman/listinfo/openflow-discuss
