A hacker can easily find out the authorized MAC address, change their network card’s MAC address to the authorized ones and poison the ARP cache to prevent the owner’s machine from connecting to it. Most of the time they’d also enable a second line of defense which is the MAC address filtering to only allow authorized devices to connect to their wireless network but they’re wrong. WEP encryption is very weak and can be cracked in less than 5 minutes using BackTrack Linux. In another scenario, some people may still be using WEP encryption for their wireless network because some old devices don’t support WPA.
So basically your ISP is capable of tracking your location by your IP address, time and the MAC address of your modem or router. Only your Internet Service Provider (ISP) can detect the MAC address of your modem or router. One thing you should know is the MAC address on your computer’s network card will not get passed out to the Internet so there is no way a website or an Internet server can capture this information. To view your network card’s MAC address, just run the command “ ipconfig /all” in command prompt and refer to the value of Physical Address. Although these information can be configured to have the same, it would cause conflict and connection problems. Every network card contains a unique code called MAC address that is permanently assigned to it, similarly like every computer requires a unique IP address to be connected to a network.
