Netgear XCM8806 - 8800 SERIES 6-SLOT CHASSIS SWITCH ユーザーズマニュアル

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Chapter 17.  Security  
NETGEAR 8800 User Manual 
Port            Circuit-ID Port information string
----            ----------------------------------
1               cutomer-1
2               cutomer-2
3               1003
4               1004
5               1005
6               1006
7               1007
8               1008
9               1009
10              1010
11              1011
12              1012
13              1013
14              1014
15              1015
16              1016
17              1017
18              1018
19              1019
20              1020
21              1021
22              1022
23              1023
24              1024
25              1025
26              1026
Note: The full Circuit ID string has the form '<Vlan Info>-<Port Info>'
* XCM8806.53 #
Source IP Lockdown
Another type of IP security prevents IP address spoofing by automatically placing source IP 
address filters on specified ports. This feature, called source IP lockdown, allows only traffic 
from a valid DHCP-assigned address obtained by a DHCP snooping-enabled port to enter 
the network. In this way, the network is protected from attacks that use random source 
addresses for their traffic. With source IP lockdown enabled, end systems that have a DHCP 
address assigned by a trusted DHCP server can access the network, but traffic from others, 
including those with static IP addresses is dropped at the switch.
Source IP lockdown is linked to the “DHCP snooping” feature. The same DHCP bindings 
database created when you enable DHCP snooping is also used by source IP lockdown to 
create ACLs that permit traffic from DHCP clients. All other traffic is dropped. In addition, the 
DHCP snooping violation action setting determines what action(s) the switch takes when a 
rogue DHCP server packet is seen on an untrusted port.
When source IP lockdown is enabled on a port, a default ACL is created to deny all IP traffic 
on that port. Then an ACL is created to permit DHCP traffic on specified ports. Each time