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(See the description for SubMask on page 3-74.)
• Service Type – Packet priority settings based on the following criteria:
- Precedence – IP precedence level. (Range: 0-7)
- TOS – Type of Service level. (Range: 0-15)
- DSCP – DSCP priority level. (Range: 0-64)
• Protocol – Specifies the protocol type to match as TCP, UDP or
Others, where others indicates a specific protocol number (0-255).
(Options: TCP, UDP, Others; Default: TCP)
• Src/Dst Port – Source/destination port number for the specified
protocol type. (Range: 0-65535)
• Src/Dst Port Bitmask – Decimal number representing the port bits
to match. (Range: 0-65535)
• Control Code – Decimal number (representing a bit string) that
specifies flag bits in byte 14 of the TCP header. (Range: 0-63)
• Control Bitmask – Decimal number representing the code bits to
match.
The control bitmask is a decimal number (for an equivalent binary bit
mask) that is applied to the control code. Enter a decimal number,
where the equivalent binary bit “1” means to match a bit and “0”
means to ignore a bit. The following bits may be specified:
-1 (fin) – Finish
- 2 (syn) – Synchronize
- 4 (rst) – Reset
- 8 (psh) – Push
- 16 (ack) – Acknowledgement
- 32 (urg) – Urgent pointer
For example, use the code value and mask below to catch packets with
the following flags set:
- SYN flag valid, use control-code 2, control bitmask 2
- Both SYN and ACK valid, use control-code 18, control bitmask 18
- SYN valid and ACK invalid, use control-code 2, control bitmask 18