3.2.1 IP
Filtering
The IP filtering function keeps unauthorized hosts from accessing to the IP serial console by specifying IP
filtering rules. It is important to fully understand what an IP filter is. If you don’t fully understand this, you will get
unexpected results against your original plan.
The IP address/Mask specifies the host range by entering base host IP address followed by / and subnet mask.
The host IP addresses to be filtered based on the rule defined. The table below gives examples of IP address/
Mask
settings.
Specified host range
Base Host IP address
Subnet mask
Any
host
0.0.0.0
0.0.0.0
192.168.1.120
192.168.1.120
255.255.255.255
192.168.1.1
~
192.168.1.254
192.168.1.0
255.255.255.0
192.168.0.1 ~ 192.168.255.254
192.168.0.0
255.255.0.0
192.168.1.1
~
192.168.1.126
192.168.1.0
255.255.255.128
192.168.1.129
~
192.168.1.254 192.168.1.128
255.255.255.128
The Port is a port or port range of the IP serial console which hosts try to access to.
Chain rule
The chain rule determines whether the access from the hosts is allowed or not. It can be one of the these two
values
:
■
ACCEPT : access allowed
■
DROP : access not allowed
When the IPCS receives a TCP packet, it will process the packet with the chain rule depicted below. The
process ordering is important; The packet will enter the chain rule 1 first, if meet the rule then take action directly,
otherwise go to chain rule 2.
TCP packet
No
Rule 1
Rule 2
Rule ..
Rule n
Default Rule
Action 1
Yes
No
No
No
Action 2
Yes
Action 3
Action 4
Action 5
Yes
Yes
Yes
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3.2 IP Filtering
Chapter 3
