Software Defined Networking/Open Flow

[Gryz]

Are any of you working on Software Defined Networking (SDN) ?
http://en.wikipedia.org/wiki/Software_Defined_Networking

Do any of you got any experience with Open Flow ?
http://en.wikipedia.org/wiki/OpenFlow

SDN/OpenFlow is supposed to replace a lot of proprietary networking software by custom written, or opensource routing software. Change the model from distributed to more centralized. Etc. But even with SDN, each element needs to have some basic routing functionality, including a distributed way of building a basic forwarding table. SDN-devices still need to run routing protocols. Thus they need an open source routing stack. Something like Quagga.
http://en.wikipedia.org/wiki/Quagga_(software)
Anyone got any experience with Quagga ?

Just curious.
Suddenly these words seem to pop up in several places.

 

[drebo]

Quagga's only real use is as a route server.

Pro tip: use a router when you need a router.

 

[Gryz]

I guess Google are amateurs then.
http://gigaom.com/cloud/how-google-is-using-openflow-to-lower-its-network-costs/

Google is a sponsor of http://opensourcerouting.org/.
They seem to be one of the pushing forces behind SDN.
" Several sponsors including Google, have helped initiate OSR to develop this new routing (Layer 3) “platform”."
So it seems Google is trying to improve Quagga. Or it is paying others to improve Quagga. I believe there is even a commercial company (http://www.vyatta.com/) that is using Quagga in their product.

I don't think there has been much serious open-source development of routing protocols. Not since gated in the nineties. (Which was a mess). I am surprised that suddenly there is a new attempt at doing this. I was wondering what others think of it.

 

[imagoon]

Quick read though makes me think of Cisco Nexus.

Basically you tell the switch you need to connect Server X to Server Y via MAC or port on a certain "network". The switch fabric (which spans the entire datacenter) takes care of making it happen and configures VLAN / routing etc on its own.

You can tell it "connect Rack 17 in row 12 Port 6 directly to rack 5 in row 2 Port 48" and the fabric just "makes it so."

 

[drebo]

That's all fine and good, Gryz, but find me one Tier 1 datacenter company or ISP (or, even, hell, a Tier 2 ISP or datacenter company) that isn't built on Cisco, Juniper, or Brocade.

Nobody is going to trust their mission critical datacenter or network of any size whatsoever to a Linux-based opensource router.

 

[Gryz]

Drebo, I am not disagreeing with you. But look at Linux. It's the most populair OS for servers worldwide. (Personally I am disappointed Linux hasn't been able to do better in the desktop market). So that is at least one success for open-source software in mission-critical deployment. Who says it can't happen with routers ? Not now, but maybe in the long run ?

If not, if routing software is supposedly so complex that only a handful of people can write it, that's fine with me too. Check out this article from 10 years ago.
The IP Priesthood

 

[imagoon]

I can't say I wouldn't be curious to see the performance of some offload network cards with a cut down linux + router environment. I think Cisco / Juniper etc have the stability thing down still.

Granted if Google went full tilt on open routing I would imagine they would lock down on a certain set of hardware to try and get to there.

 

[Halcy]

I'm in Nick McKeown's research group at Stanford where most of this originated, happy to answer any questions you have about it.

"But even with SDN, each element needs to have some basic routing functionality, including a distributed way of building a basic forwarding table. SDN-devices still need to run routing protocols. Thus they need an open source routing stack."

The routing and discovery functionality in SDN gets moved to the controller(s) and out of the switches (at least if you mean OpenFlow switches). So your controller(s) need to handle the typical routing duties performed on routers today. One example of fusing this functionality into a controller is RouteFlow: http://sites.google.com/site/routeflow/