tcpcheck.com - TCP Three-way handshake (3-way handshake) checker and analysis

Transfers slow, check your TCP buffer, window sizes
Check your and any others TCP 3-Way Handshake (SYN,SYN-ACK,ACK) below:
Want to see what is returned from curl, two requests:
curl -s -o /dev/null http://tcpcheck.com
curl -sX POST http://tcpcheck.com/runtest | python -m json.tool
Contact tcpcheck.com