2ping: 2ping (bi-directional ping utility) 2ping: 2ping: 2ping is a bi-directional ping utility. It uses 3-way pings (akin to 2ping: TCP SYN, SYN/ACK, ACK) and after-the-fact state comparison between 2ping: a 2ping listener and a 2ping client to determine which direction 2ping: packet loss occurs. 2ping: 2ping: 2ping: 2ping: 2ping: