Early engraving of Joseph Merrick But Joseph Merrick lived on, firmly believing that his mother's experience with the fairground elephant was the root of his problems. Mary Merrick became a Sunday School
TCP/IP Protocol Architecture. TCP/IP protocols map to a four-layer conceptual model known as the DARPA model , named after the U.S. government agency that initially developed TCP/IP. The four layers of the DARPA model are: Application, Transport, Internet, and Network Interface. Each layer in the DARPA model corresponds to one or more layers of the seven-layer Open Systems Interconnection (OSI) model. Figure 1.1 shows the TCP/IP protocol architecture. Figure 1.1 TCP/IP Protocol Architecture. Network Interface Layer
The TCP/IP network architecture. TCP/IP is a shorthand for the two most important protocols used to make the Internet work. The Internet Protocol (IP) is responsible for transferring these data packets, while the Transmission Control Protocol (TCP) makes sure all packets arrive safely, retransmitting them if necessary. An alternative to TCP is the User Datagram Protocol (UDP), which is an unreliable but fast protocol that is often used for data transfer. The Internet architecture is made up of five layers that work together. These five layers are, from high to low: The Application Layer; The Transport Layer; The Network Layer; The Link Layer; The Physical Layer