Security 15-35

This incoming IP packet has a source IP address that matches the network address in the Source IP Address field (00000000) in the Netopia R3100. This will NOT forward this packet.

Example 2

 

 

Filter Rule:

 

200.1.1.0

 

(Source IP Network Address)

 

 

 

 

 

 

 

 

 

 

 

 

 

255.255.255.128

 

(Source IP Mask)

 

 

 

 

 

 

 

 

 

 

 

 

 

Forward = No

 

(What happens on match)

 

 

 

 

 

 

 

 

 

Incoming packet has the source address of 200.1.1.184

 

 

 

 

 

 

 

 

 

 

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)

 

 

 

 

 

 

 

 

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 R3100. This rule WILL forward this packet because the packet does not match.

Example 3

 

 

Filter Rule:

 

200.1.1.96

 

(Source IP Network Address)

 

 

 

 

 

 

 

 

 

 

 

 

 

255.255.255.240

 

(Source IP Mask)

 

 

 

 

 

 

 

 

 

 

 

 

 

Forward = No

 

(What happens on match)

 

 

 

 

 

 

 

 

 

Incoming packet has the source address of 200.1.1.184

 

 

 

 

 

 

 

 

 

 

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)

 

 

 

 

 

 

 

 

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Image 213
Netopia R3100 manual Example