LTE with SDN controller

[daviddvs]

I am working with OpenNet framework, trying to set up a topology based on WIFI and LTE. For the moment, I have deployed an scenario with an LTE (2 UEs and a single eNodeB) and WIFI ( 2 STAs and a single AP). Both networks are connected to a wired network formed by Mininet OVS switches (5 switches and a wired host). I use an SDN controller (ONOS) to manage all the Open Flow aware components. When I send traffic (iperf) from an STA to the wired host all works properly, packets are generated and sent throw the network and the ONOS controller is capable of managing the flows. My problem is that LTE UEs are not integrated in Mininet, so the controller is not capable of recognise them. They can only exchange traffic with hosts in their LTE network. I have been looking at the code, trying to find differences between WIFI and LTE network creation. I have noticed that WIFI APs are configured through a Tap Bridge interface, and LTE eNBs using a simple Tap interface. When I try to configure the eNBs to use Tap Bridge interfaces something goes wrong with "moveIntoNamespace" function and does not run.

Do you have any idea of how to integrate the LTE network within Mininet in order to make the SDN controller aware of the LTE topology/traffic?

[kansokusha]

Hi David, here are some comment for your question.

1. LTE UE is integrated in Mininet, we have implemented it in both side of Mininet and NS-3.

2. Please notice the protocol be used between UE, eNodeB and EPC. eNodeB does not have capability to handle IP protocol packets, it only handle GTP-U packets. If UE want to exchange packets with non-LTE nodes, the packets shall be exchanged via P-GW/S-GW.

3. Please notice the packet size limitation of GTP-U tunnel, most throughput measurement tools does not consider there is a tunnel between sender and receiver.

4. Please notice the IP domain of WIFI network and LTE network may not be identical in your emulation script, and please consider to setup proper routing rules.

[daviddvs]

Hello Ting,
My eNB has the IP 10.0.0.4 and the S-GW has the IP 10.0.0.1. I have antother wired host connected to the network with the IP 10.0.0.9 and I cannot understand why the packets do not reach that host. The GTP tunnel is suposed to be created between eNB and S-GW, then , is it necessary an extra configuration for the S-GW to be able to forward those packes to the wired node?

[daviddvs]

Hi Ting,
I have realised that it was a routing issue, I have just configured the S-GW as the default gateway of the wired host (as a temporary solution for the previous example) and I got connectivity between the UEs and the wired network.
Thanks a lot for your attention!