Network topologies and protocols

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Network topologies, protocols and layers

Ethernet:

- a system for connecting a number of computer systems to form a local area network, with protocols to control the passing of information and to avoid simultaneous transmission by two or more systems.

Packet switching:

- Packet switching is a digital network transmission process in which data is broken into suitably-sized pieces or blocks for fast and efficient transfer via different network devices. When a computer attempts to send a file to another computer, the file is broken into packets so that it can be sent across the network in the most efficient way. These packets are then routed by network devices to the destination

Protocols:

- TCP/IP - The protocol which dictates how data is sent between networks it is made up of two protocols. TCP (Transmission Control Protocol) sets the rules for how devices connect on the network. It’s in charge of splitting the data into packets and reassembling the packets back into the original data once it reaches the receiving device.

- HTTP - This is set of rules for transferring files for example text, graphic images, sound, video and other multimedia files. When the user opens their web browser the user is indirectly making use of HTTP. HTTP is an application protocol that runs on top of the TCP/IP suite of protocols.

- HTTPS - Hypertext Transfer Protocol Secure - Combination of the HTTP with the Secure Socket (SSL). This is the more secure version of HTTP. Encrypts all information sent and received.

- FTP - File Transfer Protocol - Used to access, edit and move files between devices on a network to access files on a server from a client computer.

- POP - Post Office Protocol - Used to retrieve emails from a server. The server holds the email until you download it, at which point it is deleted from the server.

- IMAP - Internet Message Access Protocol - Used to retrieve emails from a server. The server holds the email until you actually delete it - you only download a copy. Used by most web-based email clients.

- SMPT - Simple Mail Transfer Protocol - Used to send emails. Also used to transfer emails between servers.

- DNS - Domain Name Server - DNS translates a website’s domain name into IP address. The internet has Domain Name Servers which means that you don’t need to remember IP addresses to access websites. The Advantages of DNS are :

More reliable - delivers messages to the users with zero downtime.

Faster

You don’t need to remember the IP addresses of websites.