Computer Networks and Data Communication Lecture 1

Study Notes

Week 1: Introduction to Data Communication and Networking.
Week 2: Network Models.
Week 3-4: Data and signal types, analog and digital transmission and Chapter 19 and 20 of Data Communications and Networking.
Week 5-7: Transmission Media and Hubs, Bridges, Switches, VLAN Trunking, VTP, MAC address flooding, Collision domain and broadcast domain, IPv4 addressing.
Week 8: Midterm Exam.
Week 9-11: IPv4 addressing, subnetting, interVLAN routing, static and default routes, dynamic routing protocols (RIP, OSPF, EIGRP).
Week 12-14: Transport Layer, Standard and Extended ACL, NAT (static, dynamic, and PAT).
Week 15: Project submission.

Telecommunication is communication at a distance.
Data is information, presented in a agreed-upon form by parties using the data.
Data communications is the exchange of data between two devices via a transmission medium. Examples include wire cables.

Simplex: Data flows in one direction. (e.g., Mainframe and Monitor)
Half-Duplex: Data flows in both directions, but only one way at a time. (e.g., two Stations)
Full-Duplex: Data flows in both directions simultaneously. (e.g., two Stations)

A network is a set of devices (nodes) connected by communication links.
Nodes can be computers, printers, or other devices sending and/or receiving data.
Links can be cables, air, optical fiber, or other transmission mediums.

Performance: Depends on network elements, measured by delay and throughput.
Reliability: Failure rate of network components, measured by availability and robustness.
Security: Data protection against corruption or loss due to errors and malicious users.

Type of Connection: Point-to-point (single transmitter and receiver), Multipoint (multiple recipients of single transmission).
Physical Topology: Connection of devices and type of transmission (unicast, multicast, broadcast).

Local Area Networks (LANs): Short distances, providing local interconnectivity.
Wide Area Networks (WANs): Long distances, providing connectivity over large areas.
Metropolitan Area Networks (MANs): Provide connectivity over larger geographic regions such as a city or campus.

The Internet has revolutionized daily life in business and leisure.
It provides a wealth of information organized for use.
Topics discussed include: Internet organization and Internet Service Providers (ISPs).

Hierarchical organization of the Internet with ISPs (Internet Service Providers), Regional ISPs, National ISPs, NAPs (Network Access Points), Tier 1 Networks, Tier 2 ISPs, and Tier 3 Network (multi-homed / single homed ISPs).

A protocol is a set of rules governing data communication.
Protocols define what is communicated, how it is communicated, and when it is communicated.
Key elements are: syntax (structure/format), semantics (meaning), and timing.

Syntax: Structure or format of the data, indicates how to read the bits (field delineation).
Semantics: Interprets the meaning of the bits (which fields define what action).
Timing: When data should be sent and at what speed.