1. CET440 Computer Networking
Fall 2017
Dr. Weifeng Chen

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

3. 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)

4. 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.

5. 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.

6. 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,

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

8. 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%

9. 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, … ???

10. Course Overview: A Comprehensive Scenario
Internet
Home network

11. 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)
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)
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

12. 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

13. 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

14. 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,

15. 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

16. 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

17. 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

18. 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

19. Course Overview: Part 6: Wireless and Mobile Networks
Wireless links, characteristics
CDMA
IEEE 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

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

21. The whole picture (an webbrowsing example)
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

22. The whole picture (an webbrowsing example)
Wireless
- How to find/connect an access point
application
transport
network
link
physical

23. The whole picture (an webbrowsing example)
Security
- How to protect information on the Internet
application
transport
network
link
physical

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