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245U-E Wireless Ethernet Modem User Manual
71
Rev Version 2.24
IP Address Filter Configuration
The IP filter can be used to permit or deny network access to specific devices through the use of blacklists
(blocking of traffic that matches a rule) and whitelists (allowing traffic that matches a rule). The IP
filter entry will match either source or destination address in the packet. That is, if either the source or
destination IP address falls within the address range specified in the rule, the packet is matched and will be
discarded (blacklist) or allowed (whitelist).
If the protocol is specified, the protocol of the packet must also match. If the protocol is TCP or UDP, the
source or destination TCP/UDP can also be inspected. If the IP address and protocol matches and the
source or destination port number falls within the range specified, the packet is matched.
NOTE Configuration pages use TCP protocol on ports 80 and 443. Create whitelist rules specifying
the configuration PC’s IP address, with TCP protocol, ports 80 and 443.
Select “Blacklist” or
“Whitelist”
Blacklist will prevent all listed devices from accessing the module and using
the radio link. Whitelist will allow devices with the IP addresses listed to
communicate with the module and utilize the radio link. All other devices are
blocked.
Add Entry
Add a row to the table of IP address filter rules.
Delete Entry
Delete the currently selected IP address filter rule.
Enable
Select this checkbox to enable the rule.
IP Address Min, IP
Address Max
These set the range of IP addresses. All addresses within the specified range
are affected by the rule.
Port Min,
Port Max
When the protocol is set to TCP or UDP, this is the range of port addresses to
which the rule applies. When the protocol is set to All or ICMP, these settings
have no effect.
Protocol
This chooses the protocol to which the rule applies. The rule can apply to Any
protocol (All), or to only one of TCP, UDP, or ICMP (Ping).
Save Changes
Save changes to non-volatile memory (reset is required to activate).
Save Changes and Reset
Save to non-volatile memory and restart to activate changes.
ARP Filter Configuration
Address Resolution Protocol (ARP) is a broadcast message and is primarily used for finding a MAC address
when only the IP or some other Network Layer address is known. On large networks, you tend to get a high
proportion of broadcast messages. Using ARP filters is useful for reducing broadcast traffic on the wireless
network by only allowing ARP requests for known units to pass, or by blocking ARP requests for high use
addresses.