A packet is the most fundamental unit of data transmission on the Internet and other TCP/IP (transmission control protocol/Internet protocol) networks. A router is an electronic device and/or software that connects at least two networks, such as two LANs (local area networks) or WANs (wide area networks), and forwards packets between them.
On most large networks, including the Internet, packets typically need to pass through several routers before they reach their final destination. Each time a packet is forwarded to the next router, a hop occurs. The more hops, the longer it takes for data to go from its source to its destination.
The hop count is the number of hops that a packet has taken towards its destination. This number is recorded in each packet header, and packets are discarded if their hop count reaches some pre-set maximum. The number of hops to any destination can be seen by using the traceroute utility.
Some Internet service providers (ISPs) advertise how few hops away from Internet backbone (i.e., high-capacity trunk lines) they are. Theoretically, the fewer hops it takes to get data to the backbone, the faster the access will be.
Created October 13, 2005. Updated March 8, 2006.