CET440 Computer Networking Fall 2017 Dr. Weifeng Chen

Today’s Class Introduction of this course Picture time & Ryker accout request

What is this course about? introductory (first) course in computer networking learn principles of computer networking learn practice of computer networking Internet architecture/protocols as case study by the time you are finished …… Goals: learn a lot (not just factoids, but principles and practice) have fun (well, it should be interesting, at least)

Course objectives explain hardware and software components of a network system, and the need for networking based on a historical perspective. identify and explain modern computer networking terms and concepts. classify network systems and various organizational topologies. identify types of common network media and communication protocols. recognize a number of protocols currently used in the computer networking industry. design a network communication architecture and demonstrate the need for robust protocol design.

Course objectives identify characteristics of packet-based data communication systems. describe network interconnecting devices and required components. troubleshoot networking problems and measure network system performance. apply course theory based on experience gained from participating in a major network design and implementation project. identify problems that occur in a network-related design project and find their solutions through step-wise debugging techniques.

Course information introductory (first) course in computer networking prerequisites: CSC124: Computer Program I CET360: Microprocessor Engineering (CET majors) course materials: Lecture: Computer Networking: A Top Down Approach Featuring the Internet, J. Kurose & K. Ross, Addison Wesley, 7th ed., 2016 Lab: Just Enough UNIX (5th ed.) P. Anderson,

Course information (more) the most important piece of info you will receive today! class WWW site, posted in D2L: http://students.calu.edu/calupa/chen/cet440/ everything is posted on this site! announcement syllabus class notes (pdf) assignments sample exams ….

Course information (more) workload: Examinations (one midterm 20% + one final 20%): 40% Term Project (team-based): 30% Lab: every Tuesday 12:15-3pm EBE 352 Home Work/Individual Lab Assignments: 25% Attendance and Class Participation: 5%

Course information (even more) Odd and ends… Me - EBE318 Office hours MWF: 10-12:30 in-class style: interaction, questions (please!) incomplete policy academic honesty getting into this course… questions, comments, … ???

Course Overview: A Comprehensive Scenario Internet Home network www.calu.edu 123.45.67.89

Course Overview: A Comprehensive Scenario DNS lookup (C.2) 1.Routing and Forwarding (C.4) 2.Longest prefix match (C.4) Layer & Encapsulation (C.1) Internet 1.CSMA/CA (C.6) 2.Address Resolution Protocol (C.5) Home network (C.1) 192.168.0.3 Obtain IP address from ISP (C.4) Network Address Translation (C.4) 1.Host name via ICANN (C.2) 2.Obtain IP address from ISP (C.4) 3.Register DNS (C.2) 4.Securing your website (C.8) 98.76.54.321 De-Multiplexing(C.3) 1.Online transaction using HTTP (C.2) 2.Establish TCP connection (C.3) 3.https based on SSL (C.8) 1.WiFi AP association (C.6) 2.DHCP obtaining IP address (C.4) lowestprice.com 123.45.67.89

Course Overview (syllabus): Part 1: Introduction what is the Internet? network edge end systems, access networks, links network core packet switching, circuit switching, network structure delay, loss, throughput in networks protocol layers, service models networks under attack: security history Most frequent IP packet size is around 64 bytes

Layers Why layers? application application presentation transport network link physical application presentation session transport network link physical Within each layer, one or more entities implement its functionality. Each entity interacts directly only with the layer immediately beneath it, and provides facilities for use by the layer above it. Protocols enable an entity in one host to interact with a corresponding entity at the same layer in a remote host. Protocol stack ISO/OSI

A top-down approach: We’ll cover networking top-down end-system applications, end-end transport network core: routing, hooking nets together link-level protocols, e.g., Ethernet other stuff: security, mobility, management,

Course Overview: Part 2: Application Layer principles of network applications Web and HTTP FTP electronic mail SMTP, POP3, IMAP DNS P2P applications socket programming with UDP and TCP

Course Overview: Part 3: Transport Layer transport-layer services multiplexing and demultiplexing connectionless transport: UDP principles of reliable data transfer connection-oriented transport: TCP segment structure reliable data transfer flow control connection management principles of congestion control TCP congestion control

Course Overview: Part 4: Network Layer virtual circuit and datagram networks what’s inside a router IP: Internet Protocol datagram format, IPv4 addressing, ICMP, IPv6 routing algorithms routing in the Internet: RIP,OSPF,BGP broadcast and multicast routing

Course Overview: Part 5: Link Layer, LANs introduction, services error detection, correction multiple access protocols LANs addressing, ARP, Ethernet, switches,VLANS link virtualization: MPLS data center networking a day in the life of a web request

Course Overview: Part 6: Wireless and Mobile Networks Wireless links, characteristics CDMA IEEE 802.11 wireless LANs (“Wi-Fi”) Cellular Internet Access Architecture, standards (e.g., GSM) Principles: addressing and routing to mobile users Mobile IP Handling mobility in cellular networks Mobility and higher-layer protocols

Course Overview: Part 8: Network Security What is network security? Principles of cryptography Message integrity, authentication Securing e-mail Securing TCP connections: SSL Network layer security: Ipsec Securing wireless LANs Operational security: firewalls and IDS

The whole picture (an webbrowsing example) https://owamail.calu.edu Web-browser (http) DNS (where is the calu.edu?) application transport network link physical Multiplexing and De-multiplexing - Gather data from multiple applications and encapsulate into packets TCP -Reliable transmission, -if the network is congested Routing - Which route is the best Router - Where to sent an outgoing packet Error detection and correction

The whole picture (an webbrowsing example) http://www.cnn.com Wireless - How to find/connect an access point application transport network link physical

The whole picture (an webbrowsing example) https://www.citibank.com Security - How to protect information on the Internet application transport network link physical

End of course overview /* */ || ? Assignments: Read Chapters 3, 7, 8, 10-12 and part IV of the Just Enough Unix