Networking

• Terms:
  • ip address
  • network interface
  • network
  • subnet
  • router
  • switching
  • NAT
  • VPN
  • Gateway
  • OSI Model
  • Load Balancing
  • DNS
  • Leased Lines
  • CoLO
  • public and private networks

Home network

• Overview
  

Concepts

• IP Address: This is a unique number given to a device in a network. It has two schemes
  • IPv4
  • IPv6
• IPv4 is a 32 bit number organized into 4 octets (8 bits) addressed as x.x.x.x
• Execute ipconfig in command prompt
  
• IP Address id combination of network id and host id

ip: 192.168.0.118
sm: 255.255.255.0

--------------------

network id (255): 1,2,3 => 192.168.0
host id (0): 4 => 118
size: bits for host id => 1 octet => 8 => 2^8 - 2 => 256-2 = 254
192.168.0.0 (network id)
192.168.0.255 (broadcast)

ip: 192.168.0.111
sm: 255.255.0.0
---------------------

network id: 1,2 => 192.168
host id: 3,4 => 0.111
size: 2 octects =>16 => 2^16-2 65536-2 = 65534

192.168.0.0 (network id)
192.168.255.255 (broadcast)

• Router is shown as Default Gateway in ipconfig

Network Principle

1. A Device can communicate directly with other device in same network
2. Router is a device which can transfer packets from one network to other