ICT102-week-1 (1).pptx

Networking LECTURE 1 Introduction to TCP/IP Networking Textbook and References: Wendell Odom (2019), CCNA 200- 301 Official Cert Guide, Volume 1. Pearson Education Recommended Reading: Vilajosana, X., Watteyne, T., Vučinić, M., Chang, T., & Pister, K. S. (2019). 6tis...

Networking LECTURE 1 Introduction to TCP/IP Networking Textbook and References: Wendell Odom (2019), CCNA 200- 301 Official Cert Guide, Volume 1. Pearson Education Recommended Reading: Vilajosana, X., Watteyne, T., Vučinić, M., Chang, T., & Pister, K. S. (2019). 6tisch: Industrial performance for ipv6 internet-of- things networks. Proceedings of the IEEE, 107(6), 1153-1165 Kurose, J. & Ross, K (2017). Computer Networking: A Top- Down Approach, (7th Ed.) Pearson. ISBN 9781292153599 Xu, K., Wan, Y., & Xue, G. (2019). 2 Powering Smart Homes with Learning Objectives: After completing this chapter, you will be able to: Define the networking concept and the network duty Understand what is enterprise network and its perspective for end-user Describe networking model and the basics of TCP/IP Explain the functionality of different layers in networking model Outline the most popular protocols in each layer and the basics of the protocols Describe the main functions of HTTP, TCP, and IP protocols Understand Error Recovery feature Explain the difference between OSI and TCP/IP networking model Discuss Data Encapsulation terminology for both OSI and TCP/IP models 3 Perspectives on Networking  Network job: moving data from one device to another.  Networks work correctly because:  Devices follow the rules  Standard and protocols defined the rules  Protocols defined in the form of networking models  Today, TCP/IP rules as the most pervasive networking model in use. Ref : dummies.com 4 Perspectives on Networking o The top part of figure shows a typical high speed cable internet user. o The lowest part of figure uses two technologies: WLAN or WiFi, and DSL End-user perspective on high-speed internet connectio 5 Perspectives on Networking What is enterprise network?  A network created by one corporation, or enterprise, for the purpose of allowing its employee to communication.  SOHO: Small Office/ Small Home, the smaller network at home when used for business purpose. Example representation of an Enterprise Network  How to build enterprise networks to deliver data 6 between devices? TCP/IP Networking Model Networking model: also called networking architecture or networking blueprint, refers to a comprehensive set of document. o Think of a networking model as an architectural blueprint for building a house! o Today, the world of computer networking uses one model: TCP/IP Historical Progression: Proprietary Models to the open TCP/IP model 7 TCP/IP Networking Model  TCP/IP model breaks the functions into Layers.  Each layer includes protocols and standards.  Layers functionalities:  Physical: how to transmit bits  Data-link: sending data over one type of physical link.  Network: delivering data from origin to destination.  Transport/Application: Focus more on the applications. 8 Application Layer: TCP/IP Application layer protocols provide services to the application software running on computer. Most popular TCP/IP application is web browser. Example protocols in Application layers: HTTP ,POP3, SMTP  What really happens to allow that web page to appear on your web browser? 9 HTTP Protocol:  To make a request for a web page and return the contents of the web page, the applications use the HyperText Transfer Protocol (HTTP). HTTP Get Request, HTTP Reply, and One Data-Only Message 1. Send a request with HTTP header to “get” a file, contain the name of the file. 2. Send a response with a return code (200 or 404) in the header, plus the first part of requested file. 10 3. Send multiple messages without HTTP header, each with a part of file.  Transport Layer:  There are small number of protocols in Transport layer. Two most commonly used are: 1. Transmission Control Protocol (TCP) 2. User Datagram Protocol (UDP)  Transport layer protocols provide services to the application layer protocols that resides one layer higher in TCP/IP model. w does a transport layer protocol provide a service to a higher-layer protocol? hat happen if some part of response has been lost?  Using error recovery service https://www.freecodecamp.org 11 TCP Error Recovery: TCP/IP needs a mechanism to guarantee delivery of data across a network. Thus: Error-recovery feature is included in TCP Acknowledgment concept is used in TCP TCP error-recovery service as provided to HTTP 12 Network Layer:  Protocols in Network Layer: Internet Protocol (IP)  IP features: addressing and routing. Compare it with postal service!  IP protocol defines a different IP address for each host computer. IP packets are forwarding from one device to another  IP defines the process of routing. Devices called routers can work as post office. Dotted-decimal notation (DD Three routers with IP addresses grouped 13 IP Routing: 1. Larry sends the packet to a nearby router on the same LAN. 2. Router R1 receives the IP packet. By comparing the destination address in the packet and R1 IP address, R1 choose to forward packet to R2. This process is IP Routing. 3. Router R2 repeat the same logic as R1 and decide to send packet to Bob. Basic routing example 14 Physical and Data Link Layer Some standards define both data link and physical layer functions. Physical layer defines the cabling and energy (e.g., electrical signals) Data link layer defines the rules and conventions when sending data over the cable. Main protocols include Ethernet protocols and 802.11 protocols. 1. IP packet is encapsulated between Ethernet header and trailer. 2. IP packet is transmitted. 3. IP packet is received on the router side. 4. IP packet is de-encapsulated from ethernet header and trailer. 15 Data Encapsulation Terminology  Encapsulation refers to the process of putting headers (and trailers) around data Five steps of Data Encapsulation 16  Names of TCP/IP messages Segment: Transport Layer Packet: Network Layer Frame: Link Layer LH: Link Header LT: Link trailer Data: encapsulated data Layers with respective terms 17 OSI Networking model  The world uses TCP/IP today rather than OSI.  The numbering is used from OSI layer, referring application layer as “Layer 7 protocol” 18 OSI Data Encapsulation Terminology  OSI uses the term Protocol Data Unit (PDU), a more generic term to refer to messages. OSI Encapsulation and Protocol Data Units 19 Summary Explain the fundamental concept and duty of the network Explain what is the enterprise network Explain networking model and TCP/IP evolution Explain TCP/IP layers and the relevant functionalities Explain different layer’s protocols and basic steps Explain TCP/IP Data Encapsulation Terminology Explain OSI networking model and its comparison with TCP/IP OSI Data Encapsulation Terminology 20