Networking is the set of technologies and practices used to connect devices and enable communication between them.

What is Networking?

Networking is the set of technologies, protocols, and practices used to connect devices and enable communication and data exchange between them.

Components

Devices

  • Switches: Network switches
  • Routers: Routers
  • Firewalls: Firewalls
  • Access Points: Access points

Media

  • Cables: Copper cables
  • Fiber: Fiber optic
  • Wireless: Wireless connectivity
  • Satellite: Satellites

Protocols

  • TCP/IP: Internet Protocol
  • Ethernet: Ethernet protocol
  • WiFi: WiFi protocol
  • DNS: Name system

Network Types

By Scope

  • LAN: Local area network
  • WAN: Wide area network
  • MAN: Metropolitan area network
  • PAN: Personal area network

By Topology

  • Bus: Bus topology
  • Star: Star topology
  • Ring: Ring topology
  • Mesh: Mesh topology

By Technology

  • Ethernet: Ethernet networks
  • WiFi: Wireless networks
  • Cellular: Cellular networks
  • Satellite: Satellite networks

Network Models

OSI

  • Layer 7: Application
  • Layer 6: Presentation
  • Layer 5: Session
  • Layer 4: Transport
  • Layer 3: Network
  • Layer 2: Data link
  • Layer 1: Physical

TCP/IP

  • Application: HTTP, FTP, SMTP
  • Transport: TCP, UDP
  • Internet: IP, ICMP
  • Link: Ethernet, WiFi

Protocols

Application Layer

  • HTTP: Hypertext Transfer Protocol
  • FTP: File Transfer Protocol
  • SMTP: Simple Mail Transfer Protocol
  • DNS: Domain Name System

Transport Layer

  • TCP: Transmission Control Protocol
  • UDP: User Datagram Protocol
  • SCTP: Stream Control Transmission Protocol
  • QUIC: Quick UDP Internet Connections

Network Layer

  • IP: Internet Protocol
  • ICMP: Internet Control Message Protocol
  • IGMP: Internet Group Management Protocol
  • OSPF: Open Shortest Path First

Configuration

Basic

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# Configure static IP
sudo ip addr add 192.168.1.100/24 dev eth0
sudo ip link set eth0 up

# Configure default route
sudo ip route add default via 192.168.1.1

# Verify configuration
ip addr show
ip route show

Advanced

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# Configure VLAN
sudo vconfig add eth0 100
sudo ip addr add 192.168.100.1/24 dev eth0.100

# Configure bonding
sudo modprobe bonding
echo "bond0" > /sys/class/net/bonding_masters

Security

Controls

  • Firewalls: Network firewalls
  • IDS/IPS: Detection systems
  • VPN: Virtual private networks
  • Segmentation: Network segmentation

Monitoring

  • SNMP: Simple Network Management Protocol
  • NetFlow: Flow analysis
  • Packet Capture: Packet capture
  • Logs: Log analysis

Use Cases

Enterprises

  • Connectivity: Internal connectivity
  • Internet: Internet access
  • Services: Network services
  • Communication: Internal communication

Data Centers

  • Servers: Server connectivity
  • Storage: Storage networks
  • Backup: Backup networks
  • Monitoring: Monitoring networks

Cloud

  • Virtualization: Virtual networks
  • Containers: Container networks
  • Microservices: Microservice networks
  • API: API networks

Best Practices

Design

  • Scalability: Scalable design
  • Redundancy: Network redundancy
  • Security: Security by design
  • Monitoring: Network monitoring

Operation

  • Maintenance: Regular maintenance
  • Updates: Firmware updates
  • Backup: Configuration backups
  • Documentation: Network documentation

Security

  • Segmentation: Segment networks
  • Monitoring: Monitor traffic
  • Access: Access control
  • Auditing: Network audits

References