User's Manual

UTT Technologies Chapter 12 Security
http://www.uttglobal.com Page 314
Undefined User: An undefined user¶s IP address and MAC address both are different
from any IP/MAC binding. The undefined users are all the users except legal and illegal
users.
It allows the legal users to access the Device and access the Internet through the Device,
and denies the illegal users. And the parameter of Allow Undefined LAN PCs
determines whether it allows the undefined users to access the Device and access the
Internet through the Device, that is, it will allow them if the Allow Undefined LAN PCs
check box is selected, else block them.
IP/MAC binding feature can act on the packets initiated from the LAN hosts to the Device
or outside hosts. When receiving a packet initiated from LAN, the Device will firstly
determine the sender¶s identity by comparing the packet with the bindings in the IP/MAC
Binding List, and then process the packet according to the sender¶s identity. The details
are as follows:
1. If the sender is a legal user, the packet will be allowed to pass, and then be further
processed by the firewall access control function module.
2. If the sender is an illegal user, the packet will be dropped immediately to prevent IP
spoofing.
3. If the sender is an undefined user, there are two cases:
1) If the Allow Undefined LAN PCs check box is selected, the packet will be
allowed to pass, and then be further processed by the firewall access control
function module.
2) Else, the packet will be dropped immediately.
For example,
if the IP/MAC address pair IP 192.168.16.65 and 00:15:c5:67:41:0f is added to
the IP/MAC Binding List, and its Allow Internet Access check box is selected, see Figure
12-3.