Re: OSPF WG Charter Proposal

["Ash, Gerald R (Jerry), ALASO" <[e-mail]>]

Dave,

> > Such failures are not the fault of the service provider 
> > operation or the vendor/equipment implementation.  They are 
> > due to shortcomings in the link-state protocols themselves -- 
> > thus the need for the enhancements proposed in the draft.

> I strongly disagree with this statement.  While the design of the
> protocols can make it challenging, there is ample room in
> implementation to provide stable and scalable networks.
> 
> When a network collapses, the fault lies at the feet of the
> implementers.  In every case I've seen (too many), the collapse was
> inevitable sooner or later, due to naive design choices in software,
> but at the same time was quite nonlinear in its onset (making any
> predictive or self-monitoring approach pretty hopeless.)
> 
> There are some things that would make the job easier, at the cost
> of additional complexity, but pointing at network collapses 
> and blaming the protocols is disingenuous.

I think you should review the ample evidence presented in http://www.ietf.org/internet-drafts/draft-ash-manral-ospf-congestion-control-00.txt that the protocols need to be enhanced to better respond to congestion collapse:

- Section 2: documented failures and their root-cause analysis, across multiple service provider networks (also review the cited references)
- Appendix B: vendor analysis of a realistic failure scenario similar to one experienced as discussed in Section 2 (perhaps you would like to provide your own analysis of this scenario based on your OSPF implementation)
- Appendix C: simulation analysis of protocol performance (other I-D's being discussed provide analysis of proposed protocol extensions)

To say that network collapse in *every* case is due to *naive design choices* ignores the evidence/analysis presented.  Based on the evidence/analysis, there is clearly room for the protocols to be improved to the point where networks *never* go down for hours or days at a time (drawing unwanted headlines & business impact).

Jerry