On 16/11/2007, Nate Duehr <nate@natetech.com> wrote:
>
> ...
> made more sense for carriers to start to upgrade the core switching and
> turn it into packet-switched networks, than to throw out PSTN switches
> right away.  Their depreciation cycles are 10 years or more on that big
> gear.
>


I think you are a few decades short there Nate,
IIRC:  A  4E is basically a souped up 1E which would have been installed in
the 60's?/70's?

Dave
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