summary

What is ISP?
ISP stands for Internet Service Provider. It is a branded company that provides its users with internet access. Using phone lines and broadband connection are the most common ways to connect to an ISP. 

Examples of famous ISP's include: 

Virgin Media


Sky broadband 

BT broadband

Orange

O2 Priority

Vodafone 

three UK 


What is an IP address?
An IP address is an Internet Protocol address. It is a unique group of numbers that are separated by full stops that represent the identities to every computer using the internet protocol to communicate over a network.

How does the internet work?

Every computer is connected together by the internet in order to communicate to each other, this is called a network. However connecting the computers together is not enough. On the internet there are specific rules of exchanging data over a computer network and they are called protocols. 

When you want to send something to someone that is too big, it would have to be broken up into small pieces for it to reach its chosen destination. On the internet these small pieces are called packets. Each of these packets include their own instructions about how they fit together as well as details about where it came from and where it is going. 

Every computer has a unique numeric address which is known as an IP address and these can easily be searched for on something called a domain name server. When the packets have an address, they get guided to it by routers which pass the packets along. Once it has arrived to its destination, the instructions help explain how to put all the packets back together. 

Homework

What is an IP address?
An IP address (a internet protocol address) is a unique group of numbers that are separated by full stops that represent the identities to every computer using the internet protocol to communicate over a network.

How to find your public IP address

A  public IP address means that an IP address can be reached from the internet. All devices in a home network are communicating with the internet from a single public IP address. You can find your IP address in you computer's settings.

People sometimes want to know the IP address of some well known websites (like YouTube) because they are unable to connect to the site by its domain name. 

These are the most common IP addresses for YouTube.com:

• 208.65.153.238
• 208.65.153.251
• 208.65.153.253
• 208.117.236.69

Static and Dynamic

Your IP address can either be static or dynamic.

Static means that your IP address generally stays the same over a long period of time.

Dynamic means that your IP address changes frequently.

Use of IP addresses

IP addresses are sometimes used for tracking. Some people might want to see who has been looking at and doing things on their website, they do this by tracking their IP address. 

Your IP address shows what region, city and town you're in when you're on the internet.

Homework

What are Data Centres?

Data centres are a large group of computer 
servers which are usually used by organizations for the remote storage, the processing and the distribution of large amounts of data. Examples of data centres include Switch SuperNAP in Nevada and Utah Data Center.  

60 Hudson Street

60 Hudson street (also known as the Western Union Building) is a telecommunications building that spans the entire block between Hudson Street, Thomas Street, Worth Street and West Broadway in the TriBeCa  neighborhood of Manhattan, New York City. 

This building handles a colossal amount of internet traffic, keeping huge chunks of the world connected.

It is a secure, power-protected environment which is used to house and operate over 300 international and domestic networks, mission critical equipment and many other things.

Telehouse

Telehouse is a major high-tech high quality carrier- neutral data centre provider situated in Docklands, London; it was founded in 1988.  Spread between Paris, London and Frankfurt, it operates eight facilities.

  

Topology

Network Topology

• Network topology is the order of the various elements (links and nodes) of a computer network. There are two ways of defining network geometry: the physical topology and the logical (or signal) topology.

The physical topology of a network is the actual geometric layout of workstations. There are many common physical typologies:

• The star topology is the basic diagram of a central computer or server which all the workstations are directly connected to. All the workstations are ultimately connected to each other through the central computer.

• The ring network topology have their workstations connected in a close loop. Pairs next to each other are directly connected while other pairs are indirectly connected.

• The bus network topology has every one of their workstations connected to a main cable called the bus. This then means that all workstations are directly connected to each other in the network.

Network Security

Network Security

Network security is the protection of networks from unauthorized users, misuse and destruction. There are 3 types of network securities: Physical security, access security and data security. 

Physical security
Physical security is the actual protection of various hardware and programs from severe losses and damage. This includes protection from fire, natural disasters, burglary, theft and vandalism.
Ways of protecting your networks from these things are:

 In case of flooding, they would put the server in a room on a higher level from the ground (in a building).

Burglary and theft can be prevented by having fences around the IT building, locking doors and windows, CCTV, alarms, making the computers heavy and (in extreme cases) sticking the computer and its computing components down onto the tables/desks.

Protection from fires include fire extinguishers and putting important IT components in a fire proof safe.


Access security
Access security is the protection of files and accounts by having things called firewalls and passwords.

Passwords are used to keep personal information secret and only available for the person who is in possession of the personal information.

Firewalls help protect networks from unauthorized access.

Data security
Data security is the protection of data from unauthorized access,corruption, and loss which means if certain data was to be lost, it would all be backed up onto a cloud or other sources.

icloud and Dropbox are examples of data back up sources.

There are also hard drives and USBs used for back up as well.