Fortinet FortiGate 100 - Manual (Page 167)

Firewall configuration Configuring IP/MAC binding for packets going to the firewall
FortiGate-100 Installation and Configuration Guide
167
For example, if the IP/MAC pair IP 1.1.1.1 and 12:34:56:78:90:ab:cd is added to the
IP/MAC binding list:
• A packet with IP address 1.1.1.1 and MAC address 12:34:56:78:90:ab:cd is
allowed to go on to be matched with a firewall policy.
• A packet with IP 1.1.1.1 but with a different MAC address is dropped immediately
to prevent IP spoofing.
• A packet with a different IP address but with a MAC address of
12:34:56:78:90:ab:cd is dropped immediately to prevent IP spoofing.
• A packet with both the IP address and MAC address not defined in the IP/MAC
binding table:
• is allowed to go on to be matched with a firewall policy if IP/MAC binding is set
to Allow traffic,
• is blocked if IP/MAC binding is set to Block traffic.
Configuring IP/MAC binding for packets going to the firewall
Use the following procedure to use IP/MAC binding to filter packets that would
normally connect with the firewall (for example, when an administrator is connecting to
the FortiGate unit for management).
1 Go to Firewall > IP/MAC Binding > Setting.
2 Select Enable IP/MAC binding going to the firewall.
3 Go to Firewall > IP/MAC Binding > Static IP/MAC.
4 Select New to add IP/MAC binding pairs to the IP/MAC binding list.
All packets that would normally connect to the firewall are first compared with the
entries in the IP/MAC binding table.
For example, if the IP/MAC pair IP 1.1.1.1 and 12:34:56:78:90:ab:cd is added to the
IP/MAC binding list:
• A packet with IP address 1.1.1.1 and MAC address 12:34:56:78:90:ab:cd is
allowed to connect to the firewall.
• A packet with IP 1.1.1.1 but with a different MAC address is dropped immediately
to prevent IP spoofing.
• A packet with a different IP address but with a MAC address of
12:34:56:78:90:ab:cd is dropped immediately to prevent IP spoofing.
• A packet with both the IP address and MAC address not defined in the IP/MAC
binding table:
• is allowed to connect to the firewall if IP/MAC binding is set to Allow traffic,
• is blocked if IP/MAC binding is set to Block traffic.
Adding IP/MAC addresses
1 Go to Firewall > IP/MAC Binding > Static IP/MAC.
2 Select New to add an IP address/MAC address pair.