The IEEE 802.3 committee is currently reviewing proposals for a 100 Mbs standard. Data-link layer handles transmission, reception and error correction. Another common type of protocol is token ring, of which various proprietary version exist, involves handing control from node to node.
Network layer handles the packet routing.
Gateways are computers which can link LANs with nothing in common at these lowest layers. Geosynchronous satellite circuits, typically leased in 128 kbs chunks. Packets can be transmitted in parallel for higher throughput. Software entities which handle the communications are called sockets.