Freeze Alarm Question

[secondcurve]

I have a freeze alarm in my house and it works great except for one problem. The phone line the freeze alarm communicates via is a cable line and when the electricity fails, the cable modem goes off and it needs to be re-set manually. Thus, after a power failure the freeze alarm can be off for long stretches of time until someone goes to the house and resets the cable modem. Is the only solution to this problem to invest in a land line?

Thanks