Friday, August 14, 2009

Round trip time measurements using ICMP and TCP

ping is a great tool for measuring round-trip time delays, but:
  1. Sometimes, ICMP is not enabled on the end hosts (increasingly now)
  2. ICMP RTTs may not provide the right delay metric for real-world applications.
I searched and found two good "TCP Ping" tools, which basically seem to create a TCP SYN message and check the time delay in getting a SYN-ACK response from the server.

This should be a more realistic measure of RTT for real-world TCP traffic and should be possible to do on any public node.

Here are two that I found to be helpful
UPDATE: scapy can do round-trip measurements itself. You need to file and some basic tutorials...