Netopia 4753 Barcode Reader User Manual


 
Security 13-25
Example 2
Incoming packet has the source address of 200.1.1.184.
This incoming IP packet (10000000) has a source IP address that does not match the network address in the
Source IP Address field (00000000) in the Netopia 4753. This rule will forward this packet because the packet
does not match.
Example 3
Incoming packet has the source address of 200.1.1.184.
Since the Source IP Network Address in the Netopia 4753 is 01100000, and the source IP address after the
logical AND is 1011000, this rule does not match and this packet will be forwarded.
Filter Rule: 200.1.1.0 (Source IP Network Address)
255.255.255.128 (Source IP Mask)
Forward = No (What happens on match)
IP Address Binary Representation
200.1.1.184 10111000 (Source address in incoming IP packet)
AND
255.255.255.128 10000000 (Perform the logical AND)
10000000 (Logical AND result)
Filter Rule: 200.1.1.96 (Source IP Network Address)
255.255.255.240 (Source IP Mask)
Forward = No (What happens on match)
IP Address Binary Representation
200.1.1.184 10111000 (Source address in incoming IP packet)
AND
255.255.255.240 11110000 (Perform the logical AND)
10110000 (Logical AND result)