1. Protocols

2. Protocol Set of rules that govern: Connection Communication data transfer Protocols regulate: access method allowed physical topologies types of cabling speed of data transfer

3. Internet Protocols http https SMTP ftp

4. Hypertext Transfer Protocol (HTTP) Protocol used by the World Wide Web Transfers displayable web pages Related web page files

5. Hypertext Transfer Protocol over Secure Socket Layer (HTTPS) Additional encryption/authentication layer Used in security-sensitive communication payment transactions corporate logons Reasonable protection from eavesdroppers and attacks

6. Simple Mail Transfer Protocol (SMTP) Used for sending and receiving e-mail only.

7. File Transfer Protocol (FTP) Used to transfer data from one computer to another through a network, such as the Internet FTP client FTP server Does not depend on specific operating system

8. Network Protocol  Defines rules for communication between network devices  Send and receive messages in the form of packets  Designed for specific purposes and environments

9. Network Protocol…Cont’d The most common protocols are: Ethernet AppleTalk Token Ring FDDI

10. Ethernet Most widely used protocol Each computer listens to the cable before sending anything through the network Transmission waits for clear cable Collision when transmission sent at same time Transmission resubmitted Delay is minimal Allows for linear bus, star, or tree topologies Transmission speed of 10 Mbps

11. Fast Ethernet Increased speed to 100 Mbps Additional network devices and cables

12. AppleTalk Developed by Apple for Macintosh computers Allows for linear bus or star topologies Transmission speed is only 230 Kbps

13. Token Ring Developed by IBM in the mid-1980s. Signal travels around the network from one computer to another in a logical ring. Requires a star-wired ring Transmission speeds of 4 Mbps or 16 Mbps

14. Fiber Distributed Data Interface (FDDI) Interconnects two or more LANs, often over large distances Requires a dual ring topology Transmission speed of100 Mbps

15. Network Protocol Summary ProtocolSpeedTopology Ethernet10 MbpsLinear Bus, Star, or Tree Fast Ethernet100 MbpsStar AppleTalk230 KbpsLinear Bus, or Star Token Ring4 Mbps – 16 MbpsStar-wired Ring FDDI100 MbpsDual Ring

16. Communications Protocols Rules for efficiently transmitting data from one network node to another Divide messages into packets Affix addresses to packets Initiate transmission Regulate flow of data Check for transmission errors Acknowledge receipt of transmitted data