Vandalism in Arizona Shut Down Internet, Cellphone, Telephone Service Across State | Washington Free Beacon

[Rob Seastrom]

Tom Azlin W7SUA <tom at nilza.org> writes:

> I will go check out the URL you provided to understand the physical
> layer some more.

SONET is typically built in rings, so there are two ways to everything
with auto-failover, unless someone cheaped out and built the circuits
non-redundant at the conduit-in-ground layer.

For Internet stuff, assuming you have more than one way in and out,
routing protocols (if properly configured, which is often a big if)
will do the rerouting.  Capacity issues when a link is missing out of
the equation are a separate issue.

Ethernet-based services (for instance, cell tower backhaul) can be
provisioned with some sort of layer 2 redundancy, or provisioned over
MPLS in which case the IP routing protocols do the heavy lifting.

In general, places built as a stub are built that way because of
straight up economics.  The geography makes it more costly to build,
but it's rare to find a place that has only one road or railroad
(pre-made right-of-way) in and out of town.

-r