Computer Networks and Internet Chapter 4

LAN vs. WAN

• The primary characteristic that distinguishes a LAN from a WAN is geographic scope. LANs are typically confined to a single building or location, while WANs connect devices across wider geographical areas.

Network Topologies

• Star topology uses a central device (hub or switch) to connect all network devices.
• Bus topology uses a shared line (bus) for communication between all devices. A common failure scenario is a break in the shared line, leading to complete network disruption.

Function of WAN

• The primary function of a WAN is to connect different LANs or networks over long distances.

Physical Arrangement of Devices

• The physical arrangement of devices in a network is referred to as network topology.

Central Device Failure in Star Topology

• A central device failure in Star topology can result in the disconnection of all devices connected to it.

Modem Function

• The primary function of a modem in a computer system is to convert digital data to analog signals (modulation) and vice versa (demodulation) for transmission over telephone lines.

ADSL Technology

• A special filter installed on a subscriber's telephone line in ADSL technology is used to separate the voice and data signals.
• The typical upstream to downstream speed ratio in ADSL connections is asymmetrical, favoring downstream speeds for faster downloads.

Network Speed and Bandwidth

• Bandwidth describes the amount of information transmitted over a network within a specific timeframe.
• Throughput refers to the speed of sending data to other network devices.
• Download speed refers to the speed of receiving data from a network.

Chapter Focus and Learning Outcomes

• The chapter focuses on network fundamentals and concepts, encompassing basic definitions, network topologies, and communication technologies.
• The main goal for students is to develop an understanding of how networks function and their key components.
• One learning outcome includes gaining knowledge of different physical transmission media used in networks.

Communication Channels and Physical Transmission Media

• The chapter explores various communication channels, including wired and wireless.
• One type of physical transmission media discussed is fiber-optic cable.

Reference Books

• The chapter does not mention any specific reference books for further reading.

Internet Connection Speed Unit

• The unit of measurement for the Internet connection speed of 8 Mbps is Megabits per second.

Bus Topology Failure

• If the shared line in a Bus topology fails, the entire network becomes disconnected as data cannot be transmitted.

Switch Function in a Network

• A Switch in a network functions as a layer 2 device that forwards data packets to their intended destination based on MAC addresses.

Cable Costs

• Fiber-optic cable is more expensive than other types of cabling, like coaxial or twisted-pair.

Server Function in Client-Server Architecture

• In Client-Server architecture, the server's primary function is to provide resources and services to the client devices connected to it.

Modem Function in a Network

• In a network, a modem is used to convert digital data to analog signals for transmission over physical lines.

Peer-to-Peer Architecture Limit

• The maximum number of computers efficiently connected in a Peer-to-Peer architecture is limited, depending on the network infrastructure and resources. However, a large number of computers can be connected, particularly with the use of modern technologies.

IP Address Classification

• The IP address 192.186.100.0 is classified as a Class C IP address, which typically represents a private network.

Protocol Purpose in a Network

• Protocols in a network establish a common language for communication, ensuring that devices understand each other's messages and can exchange information effectively.

Transmission Path

• The physical path through which data is transmitted in a network is called the transmission medium.

Peer-to-Peer Advantage

• The primary advantage of a Peer-to-Peer architecture is that it does not require a dedicated server, reducing overall network costs and complexity.

Network Messages

• The messages sent between devices in a network are called data packets.