topic Re: Traffic Engineering with SDN in Software Defined Networking

Traffic Engineering with SDN

fabioasilva — Tue, 21 Jun 2016 20:50:04 GMT

Hi everyone. I am trying to develop a traffic engineering simulation sdn app, but I'm having trouble to get the traffic to go to the hosts.

Imagine this scenarium:

h0 <--> s0 <--> s1 <---> h1

I'm pinging h1 on the h0 CLI and s0 gets the first packet, applies a rule and all next pings match the rule. When I check the HP Controller Inferface via Firefox, I can see through the flows interface of each switch that s0 and s1 are getting packets that match the flow entry. Still, h0 ins't pinging h1... There are images attached to show the problem.

NOTE: I'm using a custom topology on mininet and I specified that the port between a switch and a host is 500.

Re: Traffic Engineering with SDN

ShaunWackerly — Wed, 22 Jun 2016 19:06:34 GMT

I noticed that in s0.png, you have a flow that matches ipv4_src=10.0.0.1,ipv4_dst=10.0.0.2 and applies a set_field[vlan_vid:1] action to that packet before outputting to port 1.

I'm not sure how mininet handles vlan tagging, but I don't think that hosts send packets with an 802.1q header. You might need to include push_vlan (in order to add the 802.1q header) for packets arriving from hosts, so that they can traverse the port 500 link between the switches. Then you'd also need a pop_vlan action to strip that vlan tag when the packet is output to the other host port.

Someone please correct me if this is bad information. :)

Re: Traffic Engineering with SDN

fabioasilva — Thu, 23 Jun 2016 14:20:27 GMT

It worked out as a charm, thank you very much!