MAC # as Wireless Key

My friend had purchased a Cable Modem from a local ISP for his Wireless access at home.

The Cable Modem arrived, with manual CD, etc. But he could not configure the Cable Modem because the ISP had changed the User-Id and Password. Then he contacted the ISP and was told by a techie that the ISP locked the configuration, and to gain wireless access through the Cable Modem he was given a SSID and a Wireless Key which match to the MAC #.

How safe is his Wireless access? Can some peepers find out his Wireless Key and go into his network, or for unauthorized access?

Appreciate your opinion from all you security specialists here.

Forget to mention: the Encryption configured is WPA2.

Why didn't he ask that of his ISP when he was talking to them? Call them back and ask.

Run Xirrus Wi-Fi Inspector on any Windows machine with a WiFi connection,
or WiFi Analyzer on any Android smartphone with a WiFi connection
and then get near your friends house with either one.
You will see that both the SSID and the MAC address are being broadcast.

For example:

http://www.SpywareDrGuide.com/Virtua...spector_01.gifhttp://www.SpywareDrGuide.com/Virtua...nalyzer_01.gif
(Click each image for larger views)