11-26 User’s Reference Guide
Example 2
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| 200.1.1.0 |
| (Source IP Network Address) |
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| 255.255.255.128 |
| (Source IP Mask) |
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| Forward = No |
| (What happens on match) |
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Incoming packet has the source address of 200.1.1.184. |
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| IP Address | Binary Representation |
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| 200.1.1.184 | 10111000 | (Source address in incoming IP packet) | ||||
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| AND |
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| 255.255.255.128 | 10000000 | (Perform the logical AND) | ||||
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| 10000000 | (Logical AND result) | |||
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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 4541/4542. This rule will forward this packet because the packet does not match.
Example 3
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| Filter Rule: |
| 200.1.1.96 |
| (Source IP Network Address) |
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| 255.255.255.240 |
| (Source IP Mask) |
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| Forward = No |
| (What happens on match) |
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Incoming packet has the source address of 200.1.1.184. |
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| IP Address | Binary Representation |
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| 200.1.1.184 | 10111000 | (Source address in incoming IP packet) | ||||
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| AND |
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| 255.255.255.240 | 11110000 | (Perform the logical AND) | ||||
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| 10110000 | (Logical AND result) | |||
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Since the Source IP Network Address in the Netopia 4541/4542 is 01100000, and the source IP address after the logical AND is 1011000, this rule does not match and this packet will be forwarded.
