nLayer IP transit

Richard A Steenbergen ras at
Thu Aug 1 17:30:53 UTC 2013

On Thu, Aug 01, 2013 at 10:00:49AM +1000, Mark Tees wrote:
> Howdy listers,
> I remember reading a while back that customers of nLayer IP transit 
> services could send in Flowspec rules to nLayer. Anyone know if that 
> is true/current?

We were forced to stop offering flowspec connections to customers, after 
we started experiencing a rash of issues with it. Among other things, we 
found ways for flowspec generated rules to easily cause non line-rate 
performance on Juniper MX boxes, and we had a couple of incidents where 
customer generated routes were able to cause cascading failure behaviors 
like crashing the firewall compiler processes across the entire network.

I previously mentioned some of this here:

There have also been a few other high profile outages caused by bugs in 
the Juniper implementation, for example:

As a concept I still very much like Flowspec, and wish we could continue 
to offer it to customers, but as with any "new" routing protocol there 
are significant risks of network-wide impact if the implementation is 
not stable.

IMHO Juniper has done a horrible job of maintaining support for Flowspec 
in recent years, and has effectively abandoned doing the proper testing 
and support necessary to run it in production. Until that changes, or 
until some other major router vendors pick it up and do better with it, 
I don't expect to see any major changes in this position any time soon.

Richard A Steenbergen <ras at>
GPG Key ID: 0xF8B12CBC (7535 7F59 8204 ED1F CC1C 53AF 4C41 5ECA F8B1 2CBC)

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