IP includes the ICMP control and error message protocol as an integral part. TCP allows a process on one machine to send a stream of data to a process on another. It is connection-oriented in the sense that before transmitting data, participants must establish a connection. Software implementing TCP usually resides in the operating system and uses the IP protocol to transmit information across the underlying internet. In practice, UDP also includes a checksum over the data being sent.
Hosts range in size from personal computers to supercomputers.
A special purpose, dedicated computer that attached to two or more networks and routes packets from one to the other. In particular, an IP gateway routes IP datagrams among the networks to which it connects. Gateways route packets to other gateways until they can be delivered to the final destination directly across one physical network. A network tool that lets you obtain information about local host and currently active version of the Windows Sockets. Query your implementation of the Windows Sockets to determine what basic information is available.