Computer and Networking Basics

 

Computer and Networking Basics

 

Source:www.educba.com 

Internet Protocol (IP)

·      Public IP-Used to connect to the internet

·      Private IP-Used in local Area Network (LAN)

·      IPV4-2^32-4.3 billion addresses

·      IPV6-2^128-A very very very huge number of addresses

·      Static IP-The IP that doesn’t change once assigned to a device such as computer, printer, etc.

·      Dynamic IP-The IP once got by the device changes periodically based on the lease time stated by the DHCP server.

The TCP/IP or the Transmission Control Protocol/Internet Protocol is a communication protocol suite devised to have network devices connected to the internet. On the other hand, Open Systems Interconnection or OSI is a conceptual framework, which describes the functioning of a network.

In other words, OSI model is a logical and conceptual model that defines network communication used by systems open to interconnection and communication with other systems. In addition, OSI also defines a logical network and effectively describes computer packet transfer by using various layers of protocols.

TCP/IP aids us in determining how specific a computer should be connected to the internet and how you can transmit data between them. It helps us to create a virtual network when multiple computer networks are connected together.  Further, TCP/IP model is specifically designed as a model to offer highly reliable and end-to-end byte stream over an unreliable network.

There are two communication models as described below:

1.      OSI Model

Layers		Examples
7	Application	HTTP, FTP, SMTP, Telnet
6	Presentation	JPG, PNG, GIF, HTML, CSS
5	Session	RPS, TLS, SCP
4	Transport	TCP & UDP
3	Network	IPV4, IPV6, ICMP, ARP
2	Data Link	MAC, Frame Relay
1	Physical	Ethernet, USB, DSL, ISDN

 

2.     TCP/IP Model

Layers		Examples
4	Application	HTTP, Telnet, FTP, SMTP, DNS, SNMP
3	Transport	UDP, TCP
2	Internet	IP, ICMP, ARP
1	Network	Ethernet, Frame Relay

 

a.     DNS (Domain Name System)-Is a system that translates domain names such as facebook.com to IP address such as 2.4.19.2

b.    DHCP (Dynamic Host Control Protocol)-The system that dynamically assigns IP address to a device.

c.     ARP (Address Resolution Protocol)-The protocol that translates IP to MAC address.

d.    NAT (Network Address Translation)-helps to facilitate connection between an external address and an internal system with a private IP address.

e.     MAC (Media Access Control)-is a physical address provided by a manufacturer. It is 48 bits that cannot be changed. However, these days, with the rise in technology, people usually do change the MAC address through the process known as “MAC spoofing.”

f.      VPN (Virtual Private Network)-Provides an encrypted connection through hiding your IP address.

g.     Firewall-Is a device aimed at securing the systems and/or devices in the network.

h.    Router-Is a device used to connect two or more different networks each other.

i.      Switch-Is a device used to connect two or more hosts from the same or different network. Switch sends data to the targeted devices.

j.      Hub-Is very much similar to Switch but sends data to all connected ports. Basically, used for broadcast.