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Connections for Access. FYI…. It is important that students are aware that it would be beneficial for them to take notes throughout the lesson on points that are new to them.

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slide2

FYI…

It is important that students are aware that it would be beneficial for them to take notes throughout the lesson on points that are new to them.

They will require this information to complete the homework task and also for revision purposes. You can use the ‘Take note’ (TB5 L4 R2.doc)sheet for this purpose.

slide3

Do you think of the Internet as being more like a cloud or a wire? Class vote….

Vote

Internet =

Vote

Internet =

slide4

Before we go any further it would be useful to establish/clarify what the Internet is…

http://www.youtube.com/watch?v=7_LPdttKXPc

Image by: VEER/Corina Rosu

in this lesson students are learning about
In this lesson students are learning about:
  • the communication networks that support ‘access anywhere’ (e.g. Wi-Fi (Wireless Ethernet), Wi-Fi Direct, Infrared, Bluetooth)
  • the protocols that support ‘access anywhere’
  • security measures to prevent access from certain locations (e.g. IP filtering)
at the end of this lesson students will be able to
At the end of this lesson students will be able to:
  • differentiate between methods of having ‘access anywhere’
  • recognise some of the commonly used communication protocols
  • be aware of additional security measures when accessing online systems
slide7

Making that connection

1) The most popular way of connecting to the Internet in our homes is to have the telephone line, also known as the ‘landline’, converted to broadband so that it can carry normal phone calls and Internet data at the same time.

If we want to have connection to the ‘online’ world we have to connect to the Internet ‘wire’ in some way.

All modern computers and laptops are capable of connecting to the Internet, as are many other devices, including mobiles, tablets, e-readers, televisions, video games consoles, etc.

There are two ways of connecting to the Internet ‘wire’ at home. Can you tell me what they are?

2) If you don’t have a landline or if you want to be able to use the Internet when you’re out and about, you might prefer mobile Internet from one of the mobile network providers. This can be used anywhere there’s a mobile signal but does tend to be slower and more expensive than broadband through a landline.

From the video we have just watched we have identified that the Internet is in essence a ‘wire’.

slide8

What ‘bits’ do I need?

If we consider method one first, what are all the components or ‘bits’ that we will need to make the connection to the Internet ‘wire’?

Image by: VEER/Kirill Makarov

slide9
Bits….
  • An internet service provider (ISP). This could be the company that provides the telephone line or it could be one of the many independent providers.
  • The phone line converted to broadband
  • A router
  • A microfilter(one for each active phone line in the house. This splits the signal in the telephone wire in two: voice and broadband.)

Cables:

  • A network cable to connect the router to your computer
  • A power cable
  • A cable that will go between your router and a microfilter
slide10

= any time, anywhere!

Wi-Fi

Not that long ago you would have always had to have a network cable running from your PC or laptop to make the connection to the Internet.

But now most Internet providers supply wireless routers as standard, which means that can you have ‘Wi-Fi’ – a wireless broadband connection that allows you to connect to the Internet without using any cables. It’s particularly popular for use with laptops because they can then be used in any room of the house.

Which can bring a whole new meaning to ‘any time, anywhere’!

Image by: VEER/Kirill Makarov

Image by: VEER/Ilin Sergey

Image by: VEER/Corina Rosu

slide11

Which is better…

There has been much debate on this matter, reliability and speed being the main concerns.

What would you vote for?

wired or wireless?

Image by: VEER/Corina Rosu

Image by: VEER/cherezoff

slide12

Which is better…

wired or wireless?

Vote

Vote

Image by: VEER/Corina Rosu

Image by: VEER/cherezoff

slide13

What ‘bits’ do I need to go wireless?

So if you want to go wireless within your home what are all the components or ‘bits’ that we will need to make the connection to the Internet ‘wire’?

Image by: VEER/Kirill Makarov

slide14
Bits
  • Everything that you needed for the wired connection but the router will need to be a wireless router
  • A computer with a built-in wireless adaptor or a separate adaptor
slide15

Any time, anywhere

When you use Wi-Fi out and about, what you are really doing is connecting your device to the Internet through a wireless router located nearby (e.g. in a coffee shop, on a train, etc.)

So as long as your device is wireless-enabled you can connect to the Internet while out having a coffee. This method of connecting devices uses a wireless local area network or WLAN.

Most digital devices that are currently available in shops come with a built-in Wi-Fi capability.

The place where you can use Wi-Fi to connect to the Internet is usually referred to as a Wi-Fi hotspot.

As you will know Wi-Fi is also available in lots of public places such as cafés, hotels, trains and even some buses!

Mobile Internet connection via dongle

Image by: VEER/bobboz + 3DMask

Image by: VEER/Corina Rosu

slide16

Any time, anywhere… how?

What devices? What “contracts”? What pros and cons?

Image by: VEER/Corina Rosu

slide17

Wi-Fi Direct

Has anybody heard of or used Wi-Fi Direct?

You will want to take notes here…

Considering Wi-Fi a little further and the fact that the world is falling out of love with cables, if you can use Wi-Fi to connect to the Internet can you use it to connect to other digital devices?

http://www.youtube.com/watch?feature=player_embedded&v=je2lWjfpywQ

wi fi direct
Wi-Fi Direct
  • Wi-Fi Direct is Wi-Fi without the Internet bit, taking simple tasks and providing simple connections
  • But Wi-Fi Direct can have the Internet bit too if you have a Wi-Fi router connected to the Internet
  • Wi-Fi Direct doesn\'t need a wireless access point as Wi-Fi Direct devices can connect to each other without having to go through an access point: they can establish ad-hoc networks as and when required, letting you see which devices are available and choose which one you want to connect to. If that sounds very like Bluetooth, that\'s because it is!
slide19

Piggyback connection!

  • Bluetooth
  • Infrared

There are ways of doing this, and this is known as ‘piggybacking’.

So if you can utilise a connection method first intended for connecting a device to the Internet to then connect other digital devices to each other could this be done vice versa?

Digital devices communicate with each other using a variety of wires, cables, radio signals and infrared light beams. In essence many of our digital devices talk to each other, so could we also use one of these methods to connect/talk to the Internet?

Using a Bluetooth-enabled mobile phone as a modem for Internet access on a laptop is a good alternative when there\'s no Wi-Fi service available or your regular Internet service goes down.

The main benefit of using Bluetooth instead of a USB cable for tethering or ‘piggybacking’ is that you can keep your mobile phone in your bag or pocket and still make the connection.

In essence you can use a 3G phone as a Bluetooth modem, based on basic Bluetooth paring.

Although both of these methods are considered a networking standard, neither is ideal and aren’t really a replacement for Wi-Fi. The primary goal of both Bluetooth and Infrared is to link two devices directly (such as a laptop and printer), not to connect devices to the Internet.

Bluetooth connections are typically limited to about 30 feet and Infrared can be even less, but are worth trying in an emergency!

Another method of piggybacking uses Infrared. Infrared Data Association, or IrDA, refers to technologies involved in the transmission of data between electronic devices through infrared ports.

If two IrDA devices are connected through their infrared ports but only one has Internet access, the device without Internet access will be able to access the Internet through the other device. In this way, an Internet connection can be set up quickly for a computer through a cell phone with Internet access.

  • All you need is:
  • Bluetooth-enabled mobile phone
  • Bluetooth adapter (built-in or external dongle) for your laptop
  • Data plan from your mobile provider

Image by: VEER/Corina Rosu

slide20

Communication protocols:

All communications between digital devices require that the devices agree on the format of the message being communicated.

A system of digital message formats and rules for exchanging those messages is called a ’protocol’.

Imagine the number of people communicating in the world, the different languages they use, the different devices they use, the different ways in which they transmit data and the different software they use. We would never be able to communicate worldwide if there were no ‘standards’ governing the way we communicate and the way our machines treat data. These standards are sets of rules.

  • Here are some “protocols”. Which have you heard of?
  • VoIP
  • POP
  • IMAP
  • SMTP
  • HTTP/S
slide21

Communication protocols:

HTTPS

SMTP

Data packets

POP / IMAP

  • VoIP
  • POP
  • IMAP
  • SMTP
  • HTTP/S

IP Addresses

Image by: VEER/Alexandr Mitiuc, bobboz, Alexander Yurkinskiy, Snowdon

Image by: VEER/Alexandr Mitiuc, bobboz, Alexander Yurkinskiy, Snowdon

Image by: VEER/Veronika Vasilyuk

Image by: VEER/Alexandr Mitiuc

Image by: VEER/chrisgorgio

slide22
VoIP
  • VoIP stands for Voice over Internet Protocol.
  • Internet Protocol is the set of rules governing how packets are transmitted over a network or Internet. Remember a couple of things from the video we watched at the start of the lesson?
  • Each machine has its own unique IP address to identify it
  • When data (images, files, etc.) are sent over the Internet they are broken down into packets
  • The Internet Protocol standardises the way machines over the Internet, or any IP network, forward or route their packets based on their IP addresses.

VoIP transmits the sounds you make over the standard Internet infrastructure.

It is also referred to as IP telephony or Internet telephony as it is another way of making phone calls, although now the ‘phone’ part is not always present anymore, as you can communicate without a telephone handset and just use your computer microphone and speakers. If your computer is connected to the Internet you can communicate using VoIP for free. This can also be possible with your mobile and home phones.

VoIP has a lot of advantages over the traditional phone system. The main reason why people are turning to VoIP technology is that it is a cheaper way of making calls. Skype is the most popular service that allows users to make free calls.

slide23
PoP
  • POP is short for Post Office Protocol.
  • It is a protocol used to retrieve email from a mail server. Most email applications (sometimes called an email client) use the POP protocol, although more are using the newer IMAP – Internet Message Access Protocol.
  • Remember Aunt Ruth receiving her email in the video we watched at the start of the lesson?
slide24
IMAP

At the root of your problem lies POP\'s concept of offline email access. Email messages are delivered to the server. Your email program downloads them to your computer and deletes all messages from the server immediately. This means they are all local to your computer.

While IMAP can be used for offline email access in much the same way as POP, it also provides online and disconnected mail processing. What does that mean? Basically, you operate on the mailbox that resides on the server as if it were local to your computer. Messages are not downloaded and deleted immediately, but reside on the server. There, they can be marked with several flags, for example ‘seen’, ‘deleted’, or other user-defined flags.

POP and IMAP are used for retrieving and storing email so what about a protocol for sending your email?

  • Internet message access is precisely what IMAP is for.
  • When you retrieve your email messages from your Internet service provider\'s mail server in your email program, the server and your program (the client) have traditionally used POP to talk to each other.
  • Providing a way to get email messages to your computer is what IMAP and POP share. While POP was designed to do merely that, IMAP does provide more useful functionality.
  • In a typical POP session, you will download all new messages and delete them from the server immediately. This procedure works perfectly well as long as you access your email from only one computer and only one email program. As soon as you try to work on your email from more than one machine or device things get complicated.
slide25
SMTP

The other purpose of SMTP is to set up communication rules between servers. For example, servers have a way of identifying themselves and announcing what kind of communication they are trying to perform. There are also ways to handle errors, including common things like incorrect email addresses. In a typical SMTP transaction, a server will identify itself, and announce the kind of operation it is trying to perform. The other server will authorise the operation, and the message will be sent. If the recipient address is wrong, or if there is some other problem, the receiving server may reply with an error message of some kind.

Most servers these days actually use a slightly updated version of the SMTP protocol called ESMTP (Extended Simple Mail Transfer Protocol). This was created to allow transmission of multimedia through email. When someone sends a picture or music file through their email program, ESMTP communication codes are used to identify the kind of data being transferred.

  • SMTP stands for Simple Mail Transfer Protocol.
  • SMTP provides a set of codes that simplify the communication of email messages between servers. It\'s a kind of shorthand that allows a server to break up different parts of a message into categories the other server can understand.
  • Any email message has a sender, a recipient (or sometimes multiple recipients), a message body, and usually a subject line. Once that message goes out on the Internet, everything is turned into strings of text. This text is separated by code words or numbers that identify the purpose of each section. SMTP provides those codes, and email server software is designed to understand what they mean.
http s
HTTP/S
  • HTTP stands for ‘Hyper Text Transfer Protocol’.
  • It is the primary technology protocol on the Web that allows linking and browsing.
  • You will see this in the URL address of a website. The other acronym that you might have spotted in a URL is HTTPS.

This is stands Hyper Text Transfer Protocol’ with a ‘Secure’ layer. This protocol is primarily for safe Internet transactions.

So when you navigate to a site such as Amazon or eBay and you go to pay for something, either through a secure shopping cart or an outside payment system such as Paypal, you should see the address in your browser address bar change if the site you have arrived at is a https site, because the https in front of the URL indicates that you are now in a ‘secure session’.

For added security, always log out of any secure session when you\'re done, and especially if you are on a computer used by other people.

slide27

IP filtering

Security from within

Every computer connected to the Internet is assigned an Internet Protocol address, (IP address) which is more or less a unique identity of the computer or the computer network. This IP address is used as part of the security measures in some protocols.

This IP address can be used for security in another way too, to stop people getting into a network.

  • So as you can see some protocols are there for added security for us, for example:
  • when we want to buy something online
  • to ensure our emails go to the right recipient.

This method is called IP filtering.

The IP address is a combination of numbers and the numbers are assigned in blocks of numbers per country. Currently there are approximately 2.8 billion IP addresses in use.

Through the IP address it is therefore possible to determine the country and other location data of visitors to a website or network. This information can be used to block or allow visitors based on the IP address.

IP filtering acts like a firewall to protect an internal network from intruders.

IP filtering lets you control what IP traffic to allow into and out of your network. Basically, it protects a network by filtering packets according to rules that you define.

plenary
Plenary
  • What the Internet is
  • The communication networks that support ‘access anywhere’ to the Internet
  • Communication protocols
  • Some additional security measures
homework
Homework

For your homework you need to answer the questions on the resource ‘Making the connection’ (TB5 L4 HW.doc). Use the notes you have made during this lesson on the resource ‘Take note!’ (TB5 L4 R2.doc) to help you.

Answer the questions as fully as you can so that this will be a helpful resource to refer back to when you come to revise.

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