Computer Network Tutorial

Introduction of Computer Network Types of Computer Network Network Topology Computer Networking Architecture Transmission Modes (Data Flow) Basic Networking Devices Integrate Services Digital Network (ISDN)


OSI Model TCP/IP Model

Physical Layer

Digital Transmission Analog Transmission Transmission Media Switching

Data Link Layer

Error detection and Error correction Data Link Control Multiple Access Aloha

Network Layer

Network Layer - Logical Address Address Mapping Unicast Routing Protocol

Transport Layer

Process to Process Delivery User Datagram Protocol Transmission Control Protocol Stream Control Transmission Protocol Session Layer and Presentation Layer

Application Layer

Domain Name System Application Protocol E-mail Cryptography


Classes of Routing Protocols Classification of Routing Algorithms Controlled Access Protocols in Computer Networks Differences between IPv4 and IPv6 Fixed and Flooding Routing Algorithms Advantages and Disadvantages of Fibre Optics Cable APIPA Difference between Active and Passive FTP Fiber Optics and its Types Method of Joining and Fusion of Fiber Optic Cable Define Framing in Computer Network Disadvantages of Computer Network Mesh Topology Diagram in Computer Network Ring Topology in Computer Network Star Topology in Computer Networks 4G Mobile Communication Technology Advantages and Disadvantages of LAN Advantages and Disadvantages of MAN Advantages and Disadvantages of WAN Application Layer in OSI Model Cyclic Redundancy Check Example Data link layer in OSI model Difference between Transport and Network Layer Hamming Code Example Network Layer in OSI Model Session Layer in OSI Model Transport Layer in OSI Model Two Port Network in Computer Networks Uses of Computer Networks What is Computer Network What is Framing in a Computer Network Advantages and Disadvantages of Bus Topology Difference between Star Topology and Bus Topology Subnetting in Computer Network Subnetting Questions and Answers What is Bus Topology What is Network Topology and Types in Computer Networks Access Control in Networking Basic Characteristics of Computer Network Benefits of SOCKS5 Proxy in Computer Networks Computer Network viva Questions Difference between BOOTP and RARP Difference Between Network Topologies and Network Protocols Difference between NFC and RFID Difference Between Point-to-Point Link and star Topology Network Differences Between MSS and MTU Differences Between Trunk Port and Access Port Different Modes of Communication in Computer Networks MIME Protocol in Computer Networks Modes of Communication in Computer Networks Network Attack in Computer Network Port Address in Networking Simplest Protocol in Computer Network Sliding Window Protocol in Computer Network Stop And Wait Protocol in Computer Networks TCP 3-Way Handshake Process in Computer Networks What is a Proxy Server What is APPN What is ICMP Protocol What is Point-to-Point Protocol What is Port Address in Networking What is the HDLC Protocol What is VRRP Protocol Difference Between Analog and Digital Signals Difference Between Hub and Repeater Difference between Repeater and Switch Difference Between Transparent Bridge and Source Routing Bridge Source Routing Bridge in Computer Networks Transparent Bridge in Computer Networks Transport Protocol in Computer Networks Types of CSMA in Computer Networks What is Wired and Wireless Networking Network Security in Computer Network Disadvantages of Extranet Difference Between TELNET and FTP Define Protocol in Computer Networks Guided Transmission Media in Computer Network What is a Gateway in a Computer Network IGMP in Computer Networks LAN Protocols in Computer Networks MAN Meaning in Computer Modulation Techniques in Computer Networks Switching in DCN TCP/IP Applications What is IGMP? What is Modem in Networking What is Non-Persistent CSMA Difference between Cell Splitting and Cell Sectoring Forouzen Computer Network

Cryptography in Computer Network

Cryptography: Cryptography is derived from the Greek word, which means "Hidden Secrets." In other words, it is an art in which we can protect our data and information. Through cryptography, we convert our data into Unreadable Secret Codes, called Cipher Text and can read this data only, which will have the secret key to decrypt it. Decrypt data is called plain text. It maintains the security and integrity of the data.

In cryptography, encryption and decryption are two processes. It is used to protect the Messages, Credit/Debit Card details, and other relevant information. In encryption, plain text is converted to ciphertext, and in decryption, the ciphertext is converted to plain text.

Cryptography in Computer Network

Cryptography has many advantages because encryption makes your data completely secure and safe. After encrypting the data, even if it is hacked or stolen, no one can access or read your data.


When you send a message using an encrypted messaging service, this service converts the message into code. After this, only the right user can read this message. Digital encryption is highly complex, so it is difficult to crack.


In cryptography, encryption is a process in which the information is converted into a secret code called ciphertext. Ciphertext cannot be easily understood, only experts can understand it. The main purpose of encryption is to secure digital data or information, which transmit via the internet.



Decryption is a process in which encrypted data is converted back to original data. The encrypted data is called ciphertext, and the original data is called plain text, and the conversion of ciphertext to plain text is called decryption.

Types of Keys

There are used three different types of the key in cryptography: a secret key, public key, and private key. The secret key is used in the symmetric-key cryptography, and the other two keys is used in the asymmetric key cryptography, as shown in the figure.

Cryptography in Computer Network

There are two types of cryptography

  1. Symmetric key cryptography
  2. Asymmetric key cryptography
Cryptography in Computer Network

Symmetric key cryptography

Symmetric key cryptography is that cryptography in which the same key (only one key) is used for encryption of plain text and decryption of ciphertext. Symmetric key cryptography is also known as secret-key cryptography.

Cryptography in Computer Network

Asymmetric key cryptography

Asymmetric key cryptography is that cryptography in which both encryption and decryption have different keys. In this, the public key is used to do encryption, and the private key is used to do the decryption. It is also called public-key cryptography.

Cryptography in Computer Network

For example, if Paul sends a message to bob, they will use the bob's public key to encrypt the message, and then bob will decrypt that message with their private key.