B.2 Ping

Ping is an indispensable tool for determining if specified IP interfaces are up.

 C:\>ping 127.0.0.1 Pinging 127.0.0.1 with 32 bytes of data: Reply from 127.0.0.1: bytes=32 time<10ms TTL=128 Reply from 127.0.0.1: bytes=32 time<10ms TTL=128 Reply from 127.0.0.1: bytes=32 time<10ms TTL=128 Reply from 127.0.0.1: bytes=32 time<10ms TTL=128 Ping statistics for 127.0.0.1:     Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), Approximate round trip times in milliseconds:     Minimum = 0ms, Maximum =  0ms, Average =  0ms 

In the above session, four ICMP request packets are sent to the loopback interface, and four ICMP response packets are received.