You would have to implement some type of netflow/snmp application that would monitor your WAN network so that if a port goes down you will be emailed. Advantnet has a nice product for netflow but it waits for a 15 min time period before it will notify you via email. And you can not adjust that, but I am sure there are other methods out there of course and other applications...
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Dallas, Texas
Telecommunications Tech
CCVP, CCNA, Net+
CCNP in the works