Nmap Development mailing list archives
Negative latency numbers shown for LAN ping scans
From: Mantas Mikulėnas <grawity () gmail com>
Date: Tue, 12 Aug 2014 08:45:26 +0300
Writing here as suggested by <https://twitter.com/bonsaiviking/status/497756679464042496>. Using Debian jessie's current nmap (6.46), a local network ping scan (-sn) reliably returns latency numbers smaller than expected: | Nmap scan report for x.x.181.203 | Host is up (0.000082s latency). | Nmap scan report for x.x.181.208 | Host is up (-0.10s latency). | Nmap scan report for x.x.181.209 | Host is up (-0.10s latency). | Nmap scan report for x.x.181.212 | Host is up (-0.099s latency). | Nmap scan report for x.x.181.217 | Host is up (0.000060s latency). Some numbers make sense, but I'm a bit concerned about the time-travel in the middle; I'd have expected around 0.000212s if comparing to the `ping` output. (.203) rtt min/avg/max/mdev = 0.201/0.294/0.461/0.067 ms (.208) rtt min/avg/max/mdev = 0.261/0.291/0.490/0.048 ms (.209) rtt min/avg/max/mdev = 0.212/0.241/0.262/0.013 ms (.212) rtt min/avg/max/mdev = 1.077/1.308/3.145/0.433 ms Version information: | Nmap version 6.46 ( http://nmap.org ) | Platform: i486-pc-linux-gnu | Compiled with: liblua-5.2.3 openssl-1.0.1h-dev libpcre-8.35 libpcap-1.6.1 nmap-libdnet-1.12 ipv6 | Compiled without: | Available nsock engines: epoll poll select It's running Linux 3.14 (i686) on bare hardware. -- Mantas Mikulėnas <grawity () gmail com> _______________________________________________ Sent through the dev mailing list http://nmap.org/mailman/listinfo/dev Archived at http://seclists.org/nmap-dev/
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- Negative latency numbers shown for LAN ping scans Mantas Mikulėnas (Aug 12)