1. Mr C Johnston ICT Teacher www.computechedu.co.uk G055 - Lecture 10 Network Protocols

2. Session Objectives Understand the meaning and use of common protocol suites used when networking computers including: TCP/IP, IPX/SPX, NetBEUI, FTP, HTTP, SMTP

3. What Is A Protocol? A protocol is a set of rules governing how computers communicate, A example of a protocol in real life is the rules of English – a sentence must start with a capital letter and end with a punctuation mark, In networking a protocol defines: how data should be sent, how its received and how computers acknowledge receipt of data, To use a protocol software will need to be installed – these often come as part of your OS or NIC driver, All computers within a network must use the same protocol in order for communication to take place.

4. Overview of Protocols 1 You need to know about the following protocols: NetBIOS – Network basic input/output system - Written by IBM, extends BIOS to support communication. Computers on a LAN communicate using either session (connection between 2 machines) or broadcast to all machines (limited message size). Uses MAC addresses to identify each NIC on the network, NetBEUI - NetBIOS Extended User Interface – extension of NetBIOS a LAN protocol that allows data to be spilt into frames which can be sent separately and reassembled by the receiving computer. Used by Microsoft home networking for file sharing and printing and is more flexible and quicker than NetBIOS. Uses MAC addresses to identify each NIC on the network, IPX/SPX - Internet packet exchange/sequenced packet exchange – creates a connection between computers with directly on a LAN or by routing data from one computer to another till it reaches its destination on a WAN. Used on Novell Netware Networks and is capable of being used on the internet as is routable but not universally supported so not really suitable. Uses MAC addresses to identify each NIC on the network,

5. Overview of Protocols 2 TCP/IP – Transmission Control / Internet Protocol - protocol which is capable of allowing data to be routed so suitable for both LANs and WANs (can send data for same destination through different routes so very useful. Works with different LAN technologies and is not OS dependant and because of this was chosen as the protocol used on the internet in 1983. TCP deals with how data will be spilt / sent (data transmission protocol), IP adds addressing (addressing protocol) FTP – File Transfer Protocol - a standard for moving files between computers on a WAN. Software used to transfer files between machines and allows files to be moved between different operating systems, HTTP – Hypertext Transfer Protocol - defines how a web page is requested (such as by hyperlink), how it is found and how it is displayed. Secure HTTP (HTTPS) is an extension to the HTTP protocol that allows encryption and authentication for extra security of transactions over the Internet,

6. Overview of Protocols 3 SMTP – Simple Mail Transfer Protocol - used in sending and receiving e- mail. Is limited in its ability to queue messages at the receiving end, so it is usually used with one of two other protocols, POP3 or IMAP, that let the user save messages in a server mailbox and download them periodically from the server. In other words, users typically use a program that uses SMTP for sending e-mail and either POP3 or IMAP for receiving e-mail.

7. TCP-IP Model Transport Network Application Link

8. Topic Exercise Complete the following reading: A2 Text Book Pages pg 34,35,39 AVCE Unit 08 Book pg51-54 - start @ chapter 3.14, Make your own postcard revision notes on the different protocols making sure your clearly describe each including the protocols features, advantages and disadvantages, Download and complete this topics past exam paper questions – complete for next lesson.