1. Understanding TCP/IP Matthew Jenkins ID:2143612

2. Contents Introduction to TCP/IP TCP/IP overview The four layers of the TCP/IP model How the TCP/IP layers coordinate Encapsulation Decapsulation Bibliography 3. Introduction to TCP/IP Transmission Control Protocol / Internet Protocol (TCP/IP) is the suite of communications protocols used to connect hosts on the internet. TCP/IP is the de facto standard for transmitting data over networks. TCP/IP is subdivided in layers: - application; - transport; - internet; and - physical. 4. TCP/IP overview Video 1. Cisco. (n.d.). The TCP/IP Model of Networking 5. The four layers of the TC/IP model Layer Description Application Defines TCP/IP application protocols and how host programs interface with transport layer services to use the network. Transport Provides communication session management between host computers. Defines the level of service and status of the connection used when transporting data. Internet Packages data into IP packets, which contain source and destination address information that is used to forward the packets between hosts and across networks. Performs routing of IP packets. Link / Physical Specifies details of how data is physically sent through the network, including how bits are electrically signalled by hardware devices that interface directly with a network medium, such as coaxial cable, optical fiber, or twisted-pair copper wire. Diagram 1. The TCP/IP Family of Internet Protocols. (n.d.) 6. How the TCP/IP layers coordinate Diagram 2. The TCP/IP Family of Internet Protocols. (n.d.) Video 2. Messer Studios. (2011). The TCP/IP Model. 7. Encapsulation Diagram 2. TCP/IP Data Encapsulation and Decapulation. (n.d.) When data moves from an upper layer to a lower level of a TCP/IP protocol stack (outgoing transmission) each layer includes a bundle of relevant information called a header along with the actual data. The data package containing the header and the data from the upper layer then becomes the data that is repackaged at the next lower level with the lower layer's header. This packing of data at each layer is known as data encapsulation. 8. Decapsulation Diagram 3. TCP/IP Data Encapsulation and Decapulation. (n.d.) The reverse process of encapsulation (or decapsulation) occurs when data is received on the destination computer. As the data moves up from the lower layer to the upper layer of TCP/IP protocol stack (incoming transmission), each layer unpacks the corresponding header and uses the information contained in the header to deliver the packet to the exact network application waiting for the data. 9. Bibliography Beal, V. (n.d.). TCP/IP. Retrieved from http://www.webopedia.com/TERM/T/TCP_IP.html The TCP/IP Family of Internet Protocols. (n.d.). Retrieved from: http://www.cellbiol.com/bioinformatics_web_development/doku.php/chapter_ 1_-_internet_networks_and_tcp-ip/1-2_the_tcp-ip_family_of_internet_protocols Cisco. (n.d.). The TCP/IP Model of Networking. Retrieved from: http://www.youtube.com/watch?v=tCRBa3fTR3A Messer Studios. (2011). The TCP/IP Model. Retrieved from: https://www.youtube.com/watch?v=HG1pIxLd_4M TCP/IP Data Encapsulation and Decapsulation. (n.d.). Retrieved from: http://www.omnisecu.com/tcpip/tcpip-encapsulation-decapsulation.php