The basic ping command syntax is "ping hostname". For example, "ping visualroute.com" and the output might look like:
TTL reply: Ping sends an ICMP echo packet (with the TTL value set to the host default) to the host listed on the ping command line. Ping expects back an ICMP 'echo reply' packet. The millisecond time displayed is the round trip time. The "TTL=245" above says that the incoming ICMP echo reply packet has its TTL field set to 245. Because this value was decremented by one at each hop on the way back, this tells us that visualroute.com is probably setting the initial TTL value to 255.
TTL Expired in Transit: Most computers today initialize the TTL value of outgoing IP Packets 128 or higher. If you ever see a reply above with a "TTL=5" (or some other low TTL number) this tells you that the computer being pinged should most likely have its default TTL value increased. Otherwise, anyone trying to communicate with the computer that is at a hop count higher than the TTL will not be able to communicate with the computer. For example, if you are 40 hops away from www.xyz.com, and www.xyz.com sets TTL fields in IP packets that it sends out to 32, the IP Packets will not reach you. They will 'expire in transmit' before they reach you.
Discover your TTL: To discover the default TTL value of your computer, 'ping localhost' and examine the TTL reply value. For older Windows machines this value is 32. For newer Windows machines, this value is 128.