The AT&T line comes in the house and splits, one line to the phone, one Ethernet line to the modem.
I will try the powering off-on.
The modem, Westell, provided by AT&T, says it was made in 2010, but I've only had it about 5 years.
I dont know what kind of speed it gets, and dont know how to find out. Nor whether the firmware has bee updated, supported. As you can see, I'm fairly computer-illiterate.