[144901] in North American Network Operators' Group
Re: wet-behind-the-ears whippersnapper seeking advice on building
daemon@ATHENA.MIT.EDU (Brett Frankenberger)
Tue Sep 20 17:19:23 2011
Date: Tue, 20 Sep 2011 16:19:19 -0500
From: Brett Frankenberger <rbf+nanog@panix.com>
To: Dorn Hetzel <dorn@hetzel.org>
In-Reply-To: <CAFrZoh3RW19=8DmBmu6424nJzgM2E4cUXm4DM4aSpA_thb8C3w@mail.gmail.com>
Cc: NANOG list <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On Tue, Sep 20, 2011 at 04:13:57PM -0400, Dorn Hetzel wrote:
>
> "full time connection to two or more providers" should be satisfied when the
> network involved has (or has contracted for and will have) two or more
> connections that are diverse from each other at ANY point in their path
> between the end network location or locations and the far end BGP peers,
> whether or not the two or more connections are exposed to one or more common
> points of failure, as long as their are any failure modes for which one
> connection can provide protection against that failure mode somewhere in the
> other connection.
The GRE tunnel configuration being discussed in this thread passes this test.
Consider the following:
ISP #1 has transit connections to upstream A and B.
ISP #2 has transit connections to upstream C and D
ISP 1 and ISP 2 peer.
Customer gets a connection to ISP #1 and runs BGP, and, over that
connection, establishes a GRE tunnel to ISP #2, and runs BGP over that
also.
I assume your last clause requires that each connection provide
protection against a failure more in the other connection (not just
that one of the two provide protection against a failure mode on the
other). This is satisfied. In my example:
ISP #1 provides protection against ISP #2 having a complete meltdown.
ISP #2 provides protection against ISP #1 losing both its upstream
connections.
-- Brett
