Computer Network Tutorial
A Computer Network is a system where two or more devices are linked together to share data, resources and information. These networks can range from simple setups, like connecting two devices in your home, to massive global systems, like the Internet. Below are the main components of a computer network.
- Node : Any device which can share or receive data. Examples of devices are laptop, mobile, printer, earbuds and server.
- Transmission Media : The medium through which devices communicate It can be a wired media like Optical Fiber and Ethernet Cables. It can also be a wireless media like WiFi, Bluetooth and Infrared.
- Protocol : The set of rules that devices use to communicate. There are many different protocols for different types of communications. Examples are HTTP (For web browsing) and SMTP (For emails).
- Networking Devices : The devices with main purpose of providing network facilities. Examples are Router, Switch, Access Point and Hub.
- Networking Applications : Software that provide an interface to communicate and share. Examples are browser, email clients and file sharing applications.
Computer networks are an important part of our daily lives. They allow devices like computers, smartphones and tablets to connect and communicate with each other. Whether you’re browsing the internet, sending an email or streaming a video, it all happens because of computer networks.
Fundamentals of Computer Network
This section introduces the core concepts behind computer networking. In this we will learn what is computer network, its benefits and characteristics, different ways networks are structured and essential hardware components involved.
- Basics of Computer Networks
- Characteristics of Computer Network
- Types of Network
- Internet, Intranet & Extranet
- Types of Network Architecture
- Types of Network Devices
Network Models
In this section foundational frameworks of Computer Networks will be discussed. These frameworks provide a standard set of rules for network communication. We will dive deep into the layered structures of the OSI and TCP/IP models. This will help us understand their purpose and comparing their approaches in organizing network functions.
Physical Layer
This section focuses on the physical aspects of data transmission, which is the very foundation of network communication. We will look into different network layouts (topologies), how data signals travel across various media and the modes used for transmission.
Data Link Layer
Data link layer is all about how data is reliably transferred between directly connected devices. We will learn about framing data, detecting and correcting transmission errors, managing data flow and various switching techniques in this layer.
- Data Link Layer
- Switching Techniques
- Virtual LAN
- Link Aggregation
- Framing
- Error Detection
- Error Correction
- Error Control
- Flow Control
- Stop and wait ARQ
- Sliding Window Protocol- Go Back N
- Sliding Window Protocol- Selective Repeat
- Piggybacking
- Data Link Layer Protocols
Network Layer
This section covers how data packets are logically addressed and routed across different interconnected networks. You will understand IP addressing schemes, including the differences between IPv4 and IPv6 and the concepts of public versus private addresses.
- Network Layer
- Classful Network Addressing
- Classless Network Addressing
- What is an IP address?
- IPv4 Header Format
- IPv4 vs IPv6
- Private vs Public IP addresses
Subnetting
This subsection focuses on IP address management, specifically explaining the important technique of subnetting. We will discover how to effectively split larger networks into smaller, more manageable subnets and calculate address ranges using subnet masks. It also covers advanced topics like Variable Length Subnet Masking (VLSM) for optimized network division.
- Subnetting basics
- Subnet masks
- Calculate network, broadcast and host addresses
- Variable Length Subnet Masking (VLSM)
- Advanced VLSM
- Supernetting
Routing
Routing is how data finds its path across complex networks in this part. In this subsection we will explore the fundamental process of routing, compare static and dynamic approaches, examine different routing algorithms and understand Network Address Translation (NAT).
- What is Routing?
- Static vs Dynamic Routing
- Link State Routing
- Distance Vector Routing
- Network Address Translation(NAT)
Network Layer Protocols
This section covers some of the key protocols used at the Network Layer. We'll look at how devices find each other on a network using ARP, how they check for issues using ICMP and how they get IP addresses automatically through DHCP. We will also get an introduction to common dynamic routing protocols like RIP, OSPF and BGP, which help networks talk to each other and keep data flowing smoothly.
- Address Resolution Protocol(ARP)
- Reverse Address Resolution Protocol(RARP)
- Dynamic Host Configuration Protocol(DHCP)
- Internet Control Message Protocol(ICMP)
- Internet Group Management Protocol(IGMP)
- Routing Information Protocol(RIP)
- Open Shortest Path First(OSPF)
- Intermediate System to Intermediate System(IS-IS)
- Enhanced Interior Gateway Routing Protocol(EIGRP)
- Border Gateway Protocol(BGP)
- Multiprotocol Label Switching(MPLS)
- Internet Protocol(IP)
- Generic Routing Encapsulation(GRE)
Transport Layer
In this section, we will find out how applications communicate reliably over a network. We'll break down the main transport layer protocols - TCP and UDP - and look at how they handle things like setting up connections, managing data flow, checking for errors and dealing with network congestion.
- Transport Layer
- TCP Protocol
- TCP 3-Way Handshake Process
- Services and Segment structure in TCP
- TCP Connection Establishment
- TCP Termination
- Congestion Control in TCP
- UDP Protocol
- TCP vs UDP Protocol
- Stream Control Transmission Protocol(SCTP)
- Datagram Congestion Control Protocol(DCCP)
- Reliable User Datagram Protocol(RUDP)
- Quick UDP Internet Connections(QUIC)
Session and Presentation Layer
This section explores the upper layers responsible for managing communication dialogues (sessions) and ensuring data is presented in a compatible format. We will learn about the functions of the Session Layer and the data translation, encryption and compression services provided by the Presentation Layer.
- Session Layer
- Functions of Session Layer
- Presentation Layer
- Services Provided by Presentation Layer
- Application Filing Protocol(AFP)
- NetWare Core Protocol (NCP)
- Secure Socket Layer (SSL)
- Remote Procedure Call(RPC)
- Point-to-Point Tunneling Protocol(PPTP)
- Multipurpose Internet Mail Extensions(MIME)
Application Layer
Application layer is closest to the end-user, where network applications directly interact with the network. This section introduces the Application Layer's role, common interaction models like client-server and fundamental internet services such as the World Wide Web and email.
Application Layer Protocols
In this section, we’ll take a closer look at the protocols that power the network applications we rely on every day. From DNS, which helps translate website names into IP addresses, to HTTP and HTTPS for browsing the web and email protocols like SMTP, POP3 and IMAP - plus tools like FTP for moving files around - we will get a solid understanding of how it all works behind the scenes.
- Domain Name System (DNS)
- File Transfer Protocol (FTP)
- Simple Mail Transfer Protocol (SMTP)
- Simple Network Management Protocol (SNMP)
- HyperText Transfer Protocol(HTTP)
- HyperText Transfer Protocol Secure(HTTPS)
- Post Office Protocol v3(POP3)
- Internet Message Access Protocol(IMAP)
- Lightweight Directory Access Protocol(LDAP)
- Network Time Protocol(NTP)
- Trivial File Transfer Protocol(TFTP)
- Network News Transfer Protocol(NNTP)
- Message Queuing Telemetry Transport(MQTT)
- Session Initiation Protocol(SIP)
- Server Message Block(SMB)
Methods of Network Security
Security is crucial in networking and this section introduces fundamental methods to protect network data and resources. Explore key concepts such as verifying user identity (authentication), scrambling data (encryption), controlling network traffic (firewalls) and restricting access based on hardware addresses.
QoS (Quality of Service)
This section focuses on managing network performance to meet the varying requirements of different applications, especially real-time services like video and voice. Learn about Quality of Service (QoS) concepts, techniques to prioritize traffic and methods for managing network congestion.
- What is QoS and Multimedia?
- Techniques for achieving QoS
- Congestion Control in Computer Networks
- Token Bucket
- Leaky Bucket
Wireless and Mobile Networking
This section will let us explore the technologies that enable networking without physical cables. We will learn about popular wireless LAN standards like Wi-Fi, short-range communication technologies such as Bluetooth and Zigbee and the principles behind mobile cellular networks.
Cloud Networking
To understand how networking concepts are adapted and applied within modern cloud computing environments we will study Cloud Networking. This section covers different cloud service delivery models, the use of Virtual Private Networks (VPNs) for secure cloud access and Network Function Virtualization (NFV).
Emerging Networking Trends
In the final section we will look towards the future of networking technology. We will briefly explore cutting-edge developments shaping the next generation of networks, such as 5G mobile technology and the flexible network slicing capabilities it enables.
Quickly review our Last Minute Notes on Computer Networks and test your knowledge with our practice quiz.
