Netopia R5300 Network Router User Manual


 
Security 13-37
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 R5000 Series Router. This rule will forward this packet
because the packet does not match.
EE
EE
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xx
aa
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33
33
Incoming packet has the source address of 200.1.1.184.
Since the Source IP Network Address in the Netopia R5000 Series Router is 01100000, and the source IP
address after the logical AND is 1011000, this rule does not match and this packet will be forwarded.
EE
EE
xx
xx
aa
aa
mm
mm
pp
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ll
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44
44
Incoming packet has the source address of 200.1.1.104.
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)
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
200.1.1.104 01101000 (Source address in incoming IP packet)
AND
255.255.255.240 11110000 (Perform the logical AND)
01100000 (Logical AND result)