3Com 4210 9-Port Configuration Manual page 372

# Specify to perform local authentication.
[Sysname-isp-aabbcc.net] scheme local
[Sysname-isp-aabbcc.net] quit
# Specify aabbcc.net as the ISP domain for MAC authentication
[Sysname] mac-authentication domain aabbcc.net
# Enable MAC authentication globally (This is usually the last step in configuring access control related
features. Otherwise, a user may be denied of access to the networks because of incomplete
configuaration.)
[Sysname] mac-authentication
After doing so, your MAC authentication configuration will take effect immediately. Only users with the
MAC address of 00-0d-88-f6-44-c1 are allowed to access the Internet through port Ethernet 1/0/2.
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