Computer Networks Lecture 1: Introduction to Computer Networks and Internet

Internet Overview

• The Internet is a global system of interconnected computer networks.

Network Edge Components

• Network edge components include devices at the interface between users and the network, such as personal computers, smartphones, and IoT devices.

Types of Communication Links

• Communication links include wired connections (copper wires, optical fibers) and wireless connections (radio spectrum).

Role of Packet Switch

• Packet switches manage the path that data packets take across the network, directing packets based on their destination.

Traditional Computing Devices

• Traditional computing devices refer to desktops, laptops, and servers typically used for processing tasks.

Micro-Processor Connected Devices

• Any device connected to the network that includes a micro-processor is referred to as a host.

Transmission Rate Measurement

• The transmission rate of a link is measured in bits per second (bps), indicating the speed of data transfer.

Forwarding Packets

• Routers are the switches used to forward packets between different networks to facilitate communication.

Packet Transmission Path

• A packet travels through a sequence of communication links and packet switches from the sending end system to the receiving end system.

Excluded Media Types

• Communication links such as satellite communications may be excluded in certain discussions but are often considered in broader contexts.

Example of Network Edge

• Examples of network edges include user devices like laptops and smartphone applications that access web services.

Definition of Protocol

• In computer networks, a protocol refers to a set of rules governing data exchange between devices.

Transport Layer Focus

• The Transport Layer primarily focuses on end-to-end communication and reliability of data transmission.

Network Core Definition

• The network core refers to the high-capacity backbone of the Internet, including routers and switches that manage data flow.

Delay Measurement in Networks

• Latency is the aspect of network performance related to the time it takes for data to travel from one point to another.

Network Layer Focus

• The Network Layer is primarily concerned with data routing and forwarding between different networks.

Router Role

• Routers direct data between networks, using routing tables to determine the best path for data.

Packet Switching Description

• Packet switching involves dividing messages into packets, which are sent independently over the network and reassembled at the destination.

Link Layer Function

• The Link Layer provides methods for transferring data across a single link, including framing, error detection, and access control.

Network Edge Context

• The term 'network edge' primarily refers to hosts and devices that utilize network services.

Minimizing Data Delay

• Bandwidth-delay product relates to the aspect of network performance focused on delivering data quickly and efficiently.

Packet Switch Function

• The primary function of a packet switch is to receive incoming packets and forward them to the appropriate output links.

Computing Devices with Micro-Processors

• Any device connected to the network with a micro-processor can be classified as a host or end device.

Link Transmission Rate

• Link transmission rate is expressed in bits per second (bps), indicating how much data can be transmitted per second.

Internet Network Core Components

• The primary components of the Internet's network core include high-speed routers, switches, and communication links.

Composition of Communication Links

• Communication links made up of copper wire, optical fiber, and radio spectrum are vital for data transmission within a network.

Data Link Layer Focus

• The Data Link Layer focuses on node-to-node data transfer and ensuring error-free transmission over the physical layer.

Devices at Network Edges

• Computing devices or hosts at the network edges are crucial in accessing and interacting with network resources.

Packet Creation Component

• The component that segments data and adds header bytes to create packets is part of the Transport Layer processes.

Packet Transmission Sequence

• The sequence of communication links and packet switches traversed by a packet highlights the importance of routing in data networks.

Travel Time Aspect

• Latency measures the time taken for data to reach its destination across a network, influencing the user experience.