[ovs-dev] GTP support to OVS upstream

[Wieger IJntema]

Dear Developers,

I would like to start a discussion to actually get native GTP tunneling
support in Openvswitch keeping it still compatible with the current
OpenFlow standard.
https://en.wikipedia.org/wiki/GPRS_Tunnelling_Protocol

I the past there has been a patch for OVS to actually have GTP support.
https://www.mail-archive.com/dev@openvswitch.org/msg56446.html, Feb 2016?,
Niti Rohilla, OVS 2.5.0
Main concern was that there was no Linux upstream GTP support.

This work is updated to work with version OVS 2.6.1
https://github.com/ashishkurian/ovs, Dec 2016, Ashish Kurian, OVS 2.6.1
I have tested it extensively if all nodes use the samen OVS version with
GTP support it works good!

It is just working like Lisp or GRE tunneling and you can set the key with
the set "tunnel_id" command from openflow.
I have used RYU as a controller to control multiple OVS switches with GTP
tunneling.

In mobile networks research there is a lot interest to get GTP support in
OVS.
Especially in development towards 5G mobile network, where Openflow is
considered a protocol to be used there as switch-controller protocol.
I'm currently testing this in "pre 5G" Core solution where GTP
encapsulation is done by OVS.

>From OSMOCOM.org there is now an GTP-U (GTP userplane) Linux upstream
implementation and it think we can use it together with the Openvswitch GTP
patch to get native GTP-U support in OVS.
https://osmocom.org/projects/linux-kernel-gtp-u/wiki, Since linux kernel
v4.7.0
https://www.kernel.org/doc/Documentation/networking/gtp.txt
http://elixir.free-electrons.com/linux/v4.8.9/source/drivers/net/gtp.c

I would like to start working on this, if you guys have suggestions or
reservations please let me know.

Regards, Wieger IJntema
TNO