+The advantage of using datagram oriented
+.Tn ICMP
+sockets is that even a non-privileged process can use
+.Tn ICMP
+echo requests to gauge the quality of the connectivity to a host,
+or to receive
+.Tn ICMP
+destination unreachable message for path MTU discovery, or to receive
+time exceeded messages for traceroute.
+.Pp