14-34 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 R2020. 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 R2020 is 01100000, and the source IP address after the logical AND is 1011000, this rule does NOT match and this packet will be passed.
