Routers thumb|right|A typical home or small office router showing the ADSL telephone line and Ethernet network cable connections A router is an internetworking device that forwards packets between networks by processing the routing information included in the packet or datagram (Internet protocol information from layer 3). The routing information is often processed in conjunction with the routing table (or forwarding table). A router uses its routing table to determine where to forward packets. A destination in a routing table can include a black hole because data can go into it, however, no further processing is done for said data, i.e. the packets are dropped.
Routers thumb|right|A typical home or small office router showing the ADSL telephone line and Ethernet network cable connections A router is an internetworking device that forwards packets between networks by processing the routing information included in the packet or datagram (Internet protocol information from layer 3) The routing information is often processed in conjunction with the routing table (or forwarding table) A router uses its routing table to determine where to forward packets A destination in a routing table can include a black hole because data can go into it however no further processing is done for said data ie the packets are dropped