• Thanks @DrAzzy @Gordon. It looks like the PI is the way to go.

    One question remains about the URL or IP address that Echo uses to touch the PI.

    http://checkip.dyndns.org/

    will get your router's web IP address.
    How to you get the router to send an Echo message on to the PI?
    Do you use the DNS to do this when the PI boots?

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