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

• TCP Ping: Download script here and more details here (requires tcptraceroute)
• Scapy TCP Ping (using Python): Doesn't seem to actually do RTT measurements... (requires python and scapy library)
  

UPDATE: scapy can do round-trip measurements itself. You need to scapy.py file and some basic tutorials...