0 or less. This prevents packets from following a loop forever. Next hop When configuring network devices the hop may refer to next hop. Next hop is the next gateway to which packets should be forwarded along the path to their final destination. A routing table usually contains the IP address of a destination network and the IP address of the next gateway along the path to the final network destination. By only storing next-hop information, next-hop routing or next-hop forwarding reduces the size of routing tables. A given gateway only knows one step along the path, not the complete path to a destination. It is also key to know that the next hops listed in a routing table are on networks to which the gateway is directly connected . Diagnostics The traceroute command can be used to measure the number of router hops from one host to another. Hop counts are often useful to find faults in a network or to discover if routing is indeed correct. Wireless ad hoc networking In a wireless ad hoc network, commonly, every participating node is also acting as a router. This means that the terms "hop" and "hop count" are often the subject of confusion. Often, the sending node is simply counted as the first hop, thus yielding the same number for "hops" for both interpretations of "hop" as "traversed routers" and "jumps from node to node". For example, RFC 6130 defines a "1-hop neighbor" as any other node that is directly reachable via the wireless interface. See also Internet Control Message Protocol Ping (networking utility) References Computer networking Routing de:Hop (Netzwerktechnologie)