Proposed F19 Feature: Ryu - Network Operating System

[Isaku Yamahata]

Hi Pete.

> On Wed, 23 Jan 2013 15:25:53 +0000
> Jaroslav Reznik <jreznik at redhat.com> wrote:
> 
> > Currently, Ryu manages network devices by using OpenFlow. You 
> > can say that Ryu is an OpenFlow Controller.
> 
> I'm just curious about something. Not saying if we need or do not need
> Ryu in Fedora, I notice that Ryu attempts to insert itself between
> OpenStack and OpenVSwitch (or actually anything that implements OpenFlow).
> What's the purpose of adding the layer, and how is it different from
> what Quantum is doing now? There has to be some kind of specific benefit.
> 
> -- Pete

Quantum has many plugins supporting many technologies.
LinuxBridge, Open vSwitch(OVS), several OpenFlow controllers (including Ryu)
and several hardware switches.
Ryu has no conceptual difference from other OVS-based OpenFlow plugins from
bird's view.
I suppose you're talking about the difference from plain Open vSwitch plugin.


Open vSwitch (any OpenFlow switch in fact) is basically designed to function
better with OpenFlow controller.
Plain OVS plugin doesn't use OpenFlow controller. So it's rather static and
utilizes small subset of OVS. For example, it doesn't react to network usage
dynamically.

On the other hand, Ryu can control OVS in finer way. For example, it provides
centralized monitoring of OVS switch.
Ryu can provides more functionality. Currently it provides three ways
for L2-isolation for tenants mac address based, vlan and GRE tunneling.
(And vxlan coming)
Potentially Ryu can control not oly OVS and but also hardware OpenFlow
switches and optimize network based on its usage(bandwith, lantecy...).


In fact, those discussion can apply to all other OVS-based OpenFlow plugins
in principle and that's the reason why Quantum has many such plugins and
many people are trying to push their OF-plugin into Quantum.
-- 
yamahata