1. Another Model?! The TCP/IP Reference Model By: Allan Johnson

2. A Bit of History The TCP/IP Model was develop by the Department of Defense in the late 60s’ to ensure data communications would not be interrupted even under the worse circumstances. Since then, TCP/IP has become the de facto method we use for data communications on the Internet.

3. The Four Layers of TCP/IP Application Includes all the functions of the OSI’s Application, Presentation, & Session layers including: Data representation Data encryption and Dialog control

4. The Four Layers of TCP/IP Application Transport Uses the TCP protocol and is responsible for quality of service issues including: Reliability Flow Control and Error Correction

5. The Four Layers of TCP/IP Application Transport Internet Uses the IP protocol and is responsible for: Path determination and Packet switching.

6. The Four Layers of TCP/IP Application Transport Network Access Internet Includes all the functions of the OSI’s Data Link & Physical layers including: processes required by IP to ensure a packet reaches its destination. all the various LAN & WAN Technologies such as 100BaseTX & Frame Relay.

7. Protocols For Each Layer FTP -File Transfer Protocol HTTP -Hypertext Transfer Protocol SMTP -Simple Mail Transfer Protocol DNS -Domain Name Service TFTP -Trivial File Transfer Protocol Application

8. Protocols For Each Layer TCP -Transmission Control Protocol UDP -User Datagram Protocol Transport Application

9. Protocols For Each Layer IP -Internet Protocol Internet Transport Application

10. Protocols For Each Layer LAN & WAN Technologies Network Access Internet Transport Application

11. Transport Network Access Internet TCP/IP OSI Application Presentation Session Transport Network Data Link Physical

12. Why Two Models!! TCP/IP is the most popular “protocol specific” model used on the Internet. However, TCP/IP does not cover all the protocols and standards we will be exploring. The OSI Model is “protocol independent.” Therefore, all topics covered in the curriculum can fit into its framework.

13. What To Know For The Test The OSI Model’s layers & their key characteristics and functions. The process of data encapsulation and the various PDUs. The TCP/IP layers and its corresponding protocols. Comparison of the two model’s layers.

14. Good Luck!!