Computer Networking: TCP/IP

Computer Networking

TCP/IP

• TCP/IP (Transmission Control Protocol/Internet Protocol) is a suite of protocols used for communication on the internet
• Divided into four layers:

  1. Network Access Layer ( Physical and Data Link layers of OSI model)

  2. Internet Layer (Network layer of OSI model)

  3. Transport Layer (Transport layer of The Open Systems Interconnection (OSI) model is a conceptual framework used to describe the architecture of telecommunications networks. Developed in the 1980s by the International Organization for Standardization (ISO), it provides a hierarchical structure for understanding the different layers of communication and data transfer in a network.

     Each layer of the OSI model serves a specific purpose, with each layer interacting with the layer above and below it to ensure the efficient transfer of data. There are seven layers in total, each with its own set of protocols and functions:

     1. Physical Layer: Defines how devices communicate over a physical medium, such as a network cable or wireless connection.
     2. Data Link Layer: Responsible for framing, error-checking, and error-correction of data as it is transmitted over the physical medium.
     3. Network Layer: Routes data between different networks and ensures data delivery to the correct destination.
     4. Transport Layer: Manages data transfer between applications, ensuring reliable and efficient data transfer.
     5. Session Layer: Establishes, manages, and terminates connections between applications.
     6. Presentation Layer: Converts data into a format that can be understood by the receiving device.
     7. Application Layer: Provides services to applications, such as sending and receiving email, browsing the web, and instant messaging.

     The TCP/IP protocol suite is a specific implementation of the OSI model, with many of its layers mapping directly to corresponding OSI model layers. However, TCP/IP also introduced some significant changes, including the combination of the OSI model's Transport and Session layers into a single entity called the Transport Layer.

     model)

  4. Application Layer (Session, Presentation, and Application layers of OSI model)

• Key protocols:
  • TCP (Transmission Control Protocol): reliable, connection-oriented
  • IP (Internet Protocol): connectionless, routing
  • UDP (User Datagram Protocol): unreliable, connectionless
  • ICMP (Internet Control Message Protocol): error-reporting and diagnostics
  • DHCP (Dynamic Host Configuration Protocol): dynamic IP address assignment

Network Topology

• Physical and logical arrangement of devices in a network
• Types:
  • Physical Topology:
    • Bus
    • Star
    • Ring
    • Mesh
  • Logical Topology:
    • Broadcast
    • Point-to-Point
    • Point-to-MultiPoint

Routing Protocols

• Used to determine the best path for forwarding packets between networks
• Types:
  • Distance-Vector Protocols:
    • RIP (Routing Information Protocol)
    • IGRP (Interior Gateway Routing Protocol)
  • Link-State Protocols:
    • OSPF (Open Shortest Path First)
    • IS-IS (Intermediate System to Intermediate System)
  • Hybrid Protocols:
    • EIGRP (Enhanced Interior Gateway Routing Protocol)

Network Security

• Threats:
  • Unauthorized access
  • Malware (viruses, worms, Trojan horses)
  • Denial of Service (DoS) attacks
• Security measures:
  • Firewalls
  • Encryption (SSL/TLS, IPSec)
  • Authentication and Authorization
  • Access Control Lists (ACLs)

Wireless Networking

• Uses radio waves to transmit data between devices
• Types:
  • WiFi (IEEE 802.11)
  • Bluetooth
  • WiMAX
• Security concerns:
  • Unauthorized access
  • Interference
  • Encryption

Cables

• Used for wired connections
• Types:
  • Coaxial cables
  • Twisted pair cables (UTP, STP)
  • Fiber optic cables

Networking Devices

• Routers: connect multiple networks, route packets
• Switches: connect multiple devices, forward packets
• Bridges: connect two networks, forward packets
• Gateways: connect multiple networks, route packets
• Modems: connect to the internet via broadband

OSI Model

• 7-layered model for network communication
• Layers:
  1. Physical (Layer 1)
  2. Data Link (Layer 2)
  3. Network (Layer 3)
  4. Transport (Layer 4)
  5. Session (Layer 5)
  6. Presentation (Layer 6)
  7. Application (Layer 7)

Computer Networking

TCP/IP

• TCP/IP is a suite of protocols used for communication on the internet
• Divided into four layers: Network Access, Internet, Transport, and Application
• TCP is a reliable, connection-oriented protocol
• IP is a connectionless, routing protocol
• UDP is an unreliable, connectionless protocol
• ICMP is used for error-reporting and diagnostics
• DHCP is used for dynamic IP address assignment

Network Topology

• Refers to the physical and logical arrangement of devices in a network
• Physical Topology types: Bus, Star, Ring, Mesh
• Logical Topology types: Broadcast, Point-to-Point, Point-to-MultiPoint

Routing Protocols

• Used to determine the best path for forwarding packets between networks
• Distance-Vector Protocols: RIP, IGRP
• Link-State Protocols: OSPF, IS-IS
• Hybrid Protocols: EIGRP

Network Security

• Threats: Unauthorized access, Malware, Denial of Service (DoS) attacks
• Security measures: Firewalls, Encryption, Authentication and Authorization, Access Control Lists (ACLs)

Wireless Networking

• Uses radio waves to transmit data between devices
• Types: WiFi, Bluetooth, WiMAX
• Security concerns: Unauthorized access, Interference, Encryption

Cables

• Used for wired connections
• Types: Coaxial cables, Twisted pair cables, Fiber optic cables

Networking Devices

• Routers: connect multiple networks, route packets
• Switches: connect multiple devices, forward packets
• Bridges: connect two networks, forward packets
• Gateways: connect multiple networks, route packets
• Modems: connect to the internet via broadband

OSI Model

• 7-layered model for network communication
• Layers: Physical, Data Link, Network, Transport, Session, Presentation, Application

Test your knowledge of TCP/IP, a suite of protocols used for communication on the internet, including its four layers and key protocols.