FIRE LTE testbeds for open experimentation

In ovs, we gather an OpenvSwitch GTP patch that allows us to manage GTP tunnels https://patchwork.ozlabs.org/patch/579431/. It was written by Niti Rohilla and Saloni Jain from TATA Consultancy Services (TCS). The patch resembles the work on GRE/VXLAN tunnels already implemented in the Linux kernel. The patch is compatible with OVS version 2.5.1, but can be also downloaded as part of OVS 2.6.1 from the git repository of Ashish Kurian https://github.com/ashishkurian/ovs. To build the OVS with the GTP support one has to follow the procedure:

git clone https://github.com/ashishkurian/ovs.git export DEB_BUILD_OPTIONS=nocheck cd ovs dpkg-buildpackage -b -us -uc cd .. dpkg -i openvswitch-common_2.6.90-1_amd64.deb
openvswitch-switch_2.6.90-1_amd64.deb

We also included a patch for a usespace marching of gtp_teid. The datapath modification of the gtp_teid is still on-going.

ovs-ofctl -O OpenFlow14 add-flow ovs-br
'in_port=X,ip,udp,tp_src=2152,tp_dst=2152,gtp_teid=0x1,action=NORMAL'

ovs-ofctl -O OpenFlow14 dump-flows ovs-br

tracker.py is a script that observes both the control plane and the data plane between the EPC and ENB, to gather the parameters required by caching.

gprs.py generates a sample GTP-U packet with TEID=1