| This is used to modify the IPv4 TTL header field. The TTL field determines |
| how many hops (routers) a packet can traverse until it's time to live is |
| exceeded. |
| .TP |
| Setting or incrementing the TTL field can potentially be very dangerous, |
| so it should be avoided at any cost. |
| .TP |
| .B Don't ever set or increment the value on packets that leave your local network! |
| .B mangle |
| table. |
| .TP |
| .BI "--ttl-set " "value" |
| Set the TTL value to `value'. |
| .TP |
| .BI "--ttl-dec " "value" |
| Decrement the TTL value `value' times. |
| .TP |
| .BI "--ttl-inc " "value" |
| Increment the TTL value `value' times. |