Nmap Essentials

Delaying and increasing probe rates

The last important timing improvement flag to understand is delaying and increasing rates directly. This is probably the most fine-tuned of the performance optimization, and should generally only be used if there is a specific problem you are trying to solve, or a situation you are trying to create.

The first of these flags, --scan-delay, specifies the amount of time that Nmap should wait, not doing anything, between probes. This can be extremely useful in slowing scans down (and sometimes speeding them up, with a low scan-delay). Again, the most common usage of slowing down scans is to avoid detection of a target administrator or security system, or to try to avoid network throttling issues. Since many systems ...