Software / Programme that will monitor up address’s

I'm not sure if this is possible for someone on here to do but people have designed for mr MT4 /5 bots that are great ...

i would like if possible a webpage based programme or app or any suggestions really that will do the following:

ping or monitor routers ext up addresses and the line or writing or GUI interface of the router be green if online ... or red if it goes offline, via broadband at that site goes offline etc ....

quite simple really but need suggestions on how you could do it and costs ....

in essence we have customers with broadband routers and need to monitor if online and when goes offine and send an alert to an email address or mobile number text or something or pop up to say when offline