Sprint and Multi-Homing

Sat Aug 24 19:29:00 UTC 1996

On Fri, 23 Aug 1996, Marc E. Hidalgo wrote:

> On Mon, 19 Aug 1996, William Allen Simpson wrote:
> > Gack!  So that's what happened to my network last Sunday!
> > 
> > Even though the provider from which we get our service claims to be
> > multi-homed with Sprint and MCI, when the Sprint link was down, no
> > traffic was flowing through MCI.
> >
> be more specific. there could be many reasons for this. most of which 
> wouldn't be Sprint's fault.

I hate to stick up for Sprint, but they are right in this case.

Assuming that you're posting from the network which is supposedly 
multi-homed, then they're lying to you.  The only route which covers your 
address space is sprints "Class B-ish" announcement of the whole /16.  
The provider isn't announcing any more-specifics to their other provider 
(MCI?) if it exists.  Effectively making you singly-homed to sprint.

We're just now getting stuff set to be announcing routes - AND - some of 
our older Sprint-provided-blocks aren't going to be announced into our 
other provider, effectively making those numbers still single-homed, 
thus encouraging the renumbering into our /18 for redundancy.

> > And in the $10M RFP that just went out for one of my clients, I'll
> > specify during my bid technical review in September that any bids that
> > include SprintLink will not be accepted.  Enough is enough.
> on what technical basis? sigh

Let's see, of my 3 competitors which don't use sprintlink:

1 Can't configure DNS correctly
1 Can't configure routing correctly
1 has perpetual "downtime difficulties".

I'd hate to see someone loose a contract just because they have sprint.  
A look in the global routing tables could prove much more enligtening 
regarding their connectivity.

To tell you the truth, I'm quite often the one who calls sprint when they 
first have problems.  I get paged within 5 minutes automatically when I 
can't reach my border router, or If I can't reach one of the naps.  A 
good provider will know when they're down due to their upstreams, and if 
BGP hasn't already taken care of it, they will manually switch to their 
other provider.

-forrestc at imach.com