Re: A tunneling proposal

[Ramakrishna Gummadi <ramki@cs.berkeley.edu>]

One can think of a simple extension to tunneling under such ISP-wide
outages---if tunnel creation fails, the second ISP initiates
non-aggregatable route announcements for the prefixes from the address
space of the first ISP who has become unreachable. This two step approach
may prove effective for fixing both small-scale temporary and large-scale
persistent problems.

It may be a good idea to examine a breakdown of the kind of failures
experiences within an ISP, because this will help judge the effectiveness
of the tunneling approach. But the primary motivation in tunneling is not
to introduce unnecessray routes into the DFZ if there is an alternative.
For example, I know that, in the context of server farms, about 20% of
outages and errors are because of local power failures, but this may not
hold in the ISP case. Does anyone have any info about the main problems
and their frequencies?

thanks,
ramki

On Mon, 16 Jul 2001, Daniel Senie wrote:

> At 05:40 PM 7/16/01, Ramakrishna Gummadi wrote:
> >I hypothesize that the only scenario where tunneling for TCP
> >and UDP fails is when the entire ISP is affected in a major way.
>
> Given economic conditions and the relative health or lack thereof of some
> providers, this alone is a significant concern. If a network is powered
> down by their bankers, customers who were multihomed via tunneling would be
> out of luck. This isn't the type of redundancy that is going to make people
> sleep well at night.
>
> People want to multihome so that any outage, from a local loop to a
> backbone carrier can occur without obliterating their connectivity. I think
> it important to keep that in mind.
>
> Tunneling is quite useful for fixing temporary problems, but I'm not
> convinced it's a worthwhile solution to the multihoming problem.
>
> -----------------------------------------------------------------
> Daniel Senie                                        dts@senie.com
> Amaranth Networks Inc.                    http://www.amaranth.com
>
>
>