NTAC Peering Working Group

[Steven Wallace <>]

IMO, for now we'll be luckly to get this feature form a single 
controller/network. It's going to be a while before such things exist across 
controllers. This is probably a good research topic for someone (e.g., what 
operations API should be exposed for network troubleshooting, and how to 
expose them). My sense is that the SDN stuff is growing up much more quickly 
in the data center space.

ssw

On May 30, 2013, at 10:59 AM, Michael H Lambert 
<>
 wrote:

> Steven,
> 
> On 30 May 2013, at 10:52, Steven Wallace wrote:
> 
>> I think you've hit on something that's going to require network engineers 
>> to re-think certain approaches to troubleshooting. IMO, the idea of an 
>> in-band probe to determine the path is simply not going to be a part of 
>> the SDN future (I could be wrong, but that's my prediction). The good news 
>> is that you no longer need it. What I mean is that the controller knows 
>> the entire path. I would be asking for an app where the engineer can 
>> easily  say to AL2S "what's the path for this flow" and the app responds 
>> with the complete path as it exists in realtime.
> 
> If there are multiple controllers, do they all contain the entire state or 
> are they just "cooperative"?  I'm trying not to think about the old mbone 
> traceroute that would do a hop-by-hop query.
> 
> Michael
>