[68409] in North American Network Operators' Group
RE: Enterprise Multihoming
daemon@ATHENA.MIT.EDU (McBurnett, Jim)
Thu Mar 11 12:24:08 2004
Date: Thu, 11 Mar 2004 12:07:09 -0500
From: "McBurnett, Jim" <jmcburnett@msmgmt.com>
To: "John Neiberger" <john.neiberger@efirstbank.com>,
<nanog@merit.edu>
Errors-To: owner-nanog-outgoing@merit.edu
Look at it this way:
If Multi-homing to ensure maximum reliabilty was not a good thing:
why would XYZ isp do it?
Take this example:
Remember last year (or year before?) when MCI had the routing issue
on the east coast? I had a friend that had 2 T-1's to MCI, he lost all =
reachability
for over 5 hours. I had another friend that had a T-1 from MCI and one =
from AT&T.
He stayed up, and so did his ecommerce site.
So the end questions is:=20
Do you trust your upstream enough to bank your business, or more =
importantly
your reputation as an IT professional, on the ability of everyone at =
your ISP
to maintain their network and everything that gives you access 99.999% =
of the time?
Jim
->-----Original Message-----
->From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu]On Behalf Of
->Gregory Taylor
->Sent: Thursday, March 11, 2004 11:41 AM
->To: John Neiberger; nanog@merit.edu
->Subject: Re: Enterprise Multihoming
->
->
->
->Mutli-homing a non-ISP network or system on multiple carriers=20
->is a good=20
->way to maintain independent links to the internet by means of=20
->different=20
->peering, uplinks, over-all routing and reliability. My=20
->network on NAIS=20
->is currently multi-homed through AT&T. I use a single=20
->provider as both=20
->of my redundant links via 100% Fiber network. Even though this is=20
->cheaper for me, all it takes is for AT&T to have some major=20
->outage and I=20
->will be screwed. If I have a backup fiber line from say, Global=20
->Crossing, then it doesn't matter if AT&T takes a nose dive, I=20
->still have=20
->my redundancy there.
->
->That is why most non-ISPs hold multihoming via different providers as=20
->their #1 choice.
->
->Greg
->
->John Neiberger wrote:
->
->>On another list we've been having multihoming discussions again and I
->>wanted to get some fresh opinions from you.=20
->>
->>For the past few years it has been fairly common for non-ISPs to
->>multihome to different providers for additional redundancy in case a
->>single provider has problems. I know this is frowned upon now,
->>especially since it helped increase the number of autonomous=20
->systems and
->>routing table prefixes beyond what was really necessary. It=20
->seems to me
->>that a large number of companies that did this could just have well
->>ordered multiple, geographically separate links to the same provider.
->>
->>What is the prevailing wisdom now? At what point do you feel=20
->that it is
->>justified for a non-ISP to multihome to multiple providers? I ask
->>because we have three links: two from Sprint and one from Global
->>Crossing. I'm considering dropping the GC circuit and adding another
->>geographically-diverse connection to Sprint, and then=20
->removing BGP from
->>our routers.
->>
->>I see a few upsides to this, but are there any real downsides?
->>
->>Flame on. :-)
->>
->>Thanks,
->>John
->>--
->>
->>
->> =20
->>
->
->
->
