Tuesday 13 October 2015

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:





topology
  • 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.



Servers


What is a server?
A server is a computer program which manages access to a unified resource or service in a network.



What are the different types of servers used in IT?
The different types of servers used in IT include: 
Server Platform, Application Server, Audio/Video Server, Chat Server, Fax Server, File server, Email server, print server  virtual server as well as many many more.

Print server

A print server (or a printer server) is a device which connects printers to a computer hardware or software through a network. The server accepts the print jobs from the computers and then sends them to the chosen printer. An advantage of print servers is the fact that it saves money.



Email server 
An email server (also known simply as a mail server) is an application that receives incoming Emails from any local users. It acts like a storage area as it is where all emails are stored. It's like a virtual post office. A disadvantage of this the risk of hacking if the correct security is not used.


File server

A file server is quite simply a server that provides access to files. It's like the central file storage location that is accessible to multiple systems. An advantage of file servers is that they can easily be shared between other users. Furthermore, data is easy to back up as it is all stored in the file server.





Home IT and school IT networks

Home IT network
A home IT network uses a router. A home router usually has 4 LAN ports (local area network port) meaning that straight out of the box, it can host a network of up to 4 wired networking devices.
 

School IT network
A school IT network holds ports for several networks meaning that it can connect to an infinite amount of computer networks.