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Business Express + 353 1 4294000 www. 48 Western Parkway Business Park Lower Ballymount Road Dublin 12 Ireland

Understanding Broadband



Author: Chris Thomson

     Philip Lacey

    Version: 1-2

    Date: 2007-10-13


    Company Number: 400703 VAT Registered Number: IE 6420703G Directors: Nick Wheeler, Chris Thomson, Philip Lacey


    + 353 1 4294000 www. 48 Western Parkway Business Park Lower Ballymount Road This is an introductory guide to the Internet and it explains some of its key Dublin 12 Ireland elements.


o How Browsing Works

    o Basic Setup

    o Download / Upload and Speeds

    o Contention

    o Download Limits

    o Lag

    o Methods

    o Download Versus Streamed Media

    o Peer to Peer Networking

    o VOIP

    How Browsing Works

The Internet doesn’t exist. It is actually a bunch of equipment all connected

    together and with the ability to send information to each other. Internet is two one words, Inter & Network, mashed down for convenience. It has now been

    shortened further to the Net.

The internet gives your equipment access to other equipment. So being on the

    net means joining your piece of equipment to a big interconnecting mass of


People use the Net to get information from these other computers. However

    you never actually look at anything on someone else’s computer, rather, you

    ask their computer for the information which is sent to your computer for you

    to look at locally.


    It’s important to understand how this information can get to you quickly.

Imagine a big poster. Your friend has this poster and you want a copy of it.

    The problem is, its big. How does your friend send it to you? Easy, put it in an envelope. But it wont fit in one envelope, so it has to cut it up into smaller

    pieces and put into lots of little envelopes and you have to put it back together

    when you get it. But this is going to take forever to do. If only your friend had

    a big envelope. The faster your Internet connection, the bigger the envelope,

    the faster you get this information.


    Company Number: 400703 VAT Registered Number: IE 6420703G Directors: Nick Wheeler, Chris Thomson, Philip Lacey

    Basic Setup

    + 353 1 4294000 www. 48 Western Parkway Business Park So what have we got? Lower Ballymount Road Dublin 12 Ireland Imagine the following, very simple setup.

You buy broadband from most suppliers It comes in over the telephone line.

    You have a pc, which you connect a broadband modem too. You get to the

    Internet through your Internet supplier.

You want to get to Google.

    You open your Internet browser. You type in 1. Your PC passes the message ‘Please get me Google’ to your modem 2. Your modem asks Eircom’s modem, ‘Please get me Google’ 3. Eircom’s modem asks their server ‘Please get me Google’ 4. Eircom’s server goes out onto the Net

    5. Google reply to Eircom

    6. Eircom passes the reply back down the line to their modem one 7. The modem hands it to your modem

    8. Your modem hands it to your PC

    9. appears on your screen

This is how the internet works. Requests for information are sent out and the

    Internet Service Provider (ISP) is responsible for passing back the information

    to you. With all this passing of requests, the faster these modems and

    computers can chat to each other and the faster any information you request

    will appear. Requests for information going out from your PC are tiny. The

    information coming back to your computer is usually a lot bigger. ‘Can I have c a movie’ is a lot less information than the movie coming back.


    Company Number: 400703 VAT Registered Number: IE 6420703G Directors: Nick Wheeler, Chris Thomson, Philip Lacey


    + 353 1 4294000 www. 48 Western Parkway Business Park There are a lot of ways to get connected Lower Ballymount Road Dublin 12 Ireland o Phone line. This is by far the most popular and is used by suppliers

    such as Eircom, Smart, & Perlico. However service is limited to those

    with an appropriate phone line

    o Phone and Satellite combination. With this system, you upload through

    the phone line at dialup speed and download at broadband speed

    through your satellite dish

o Cable. For example NTL. Existing cable customers only

o Power lines. Mainly available in the US

    o Microwave. This is the method used by Irish Broadband. It commonly

    needs an external antenna and your unit has to be in line of sight of

    the next microwave dish

    o Radio. Clearwire deploy this technology, the user needs to be near a


    o Satellite. You can use this anywhere but it is the most expensive

    technology one

    o Mobile phone. Used by Vodafone, O2 & Meteor. Again, this can be used

    anywhere within the mobile network but speeds are low and it can

    prove expensive

o WiMax. Due in Ireland in February 2008 will show you all the methods and companies that are

    available at any given address.



    Company Number: 400703 VAT Registered Number: IE 6420703G Directors: Nick Wheeler, Chris Thomson, Philip Lacey

    Download / and Upload speeds

    + 353 1 4294000 www. 48 Western Parkway Business Park Downloading is information coming back to you from the likes of Google. Lower Ballymount Road Uploading is you sending out requests. As you can imagine, for 99% of cases it Dublin 12 Ireland is far more important to be quicker downloading than uploading. Most

    broadband companies only ever advertise their download speed. The upload

    speed can be tiny and it won’t make much of a difference.

Broadband speed is measured in Kilobytes or Megabytes per second. These are

    measures of how much information will get to you in a given time. Dial up

    works at 56K (56 thousand bits of information per second) which means that if

    you wanted to send a 5 mega pixel photograph (5,120,000,000 bits large) then

    it would take about 12 minutes to download.

Broadband is available at different speeds. This table shows you the different

    times taken to download our picture.

    Speed Name Speed on File Time to

    screen Size Download 56.6 Kbps Dial Up 5.6 5 Mb 12.2 Minutes 60 Kbps GPRS 6.0 5 Mb 11.4 Minutes 64 Kbps ISDN 6.4 5 Mb 10.6 Minutes 128 Kbps ISDN 12.8 5 Mb 5.3 Minutes 236 Kbps EGPRS 23.6 5 Mb 2.9 Minutes one 384 Kbps 3G 38.4 5 Mb 1.7 Minutes 512 Kbps Broadband 51.2 5 Mb 1.3 Minutes 1 Mbps Broadband 102.4 5 Mb 40 Seconds 2 Mbps Broadband 204.8 5 Mb 20 Seconds 3 Mbps Broadband 307.2 5 Mb 13 Seconds 4 Mbps Broadband 409.6 5 Mb 10 Seconds 8 Mbps Broadband 819.2 5 Mb 5 Seconds 24 Mbps ADSL2 2457.6 5 Mb 1.6 Seconds

     An average MP3 song is about 5Mb in size. So as you can see, the faster your

    download speed the better. c

    When choosing a broadband package, check your upload speed. Most

    companies sell 128Kbps up or 256Kbps up. This is why downloading photos

    from Bebo can be quick but putting them up can take ages.

If you want to learn more about bits, bytes, kilobytes and megabytes, visit


    Company Number: 400703 VAT Registered Number: IE 6420703G Directors: Nick Wheeler, Chris Thomson, Philip Lacey


    + 353 1 4294000 www. 48 Western Parkway Business Park ISP companies put a big connection into an area, but it costs a fortune to do. Lower Ballymount Road They have to dig up the road, they have to connect it into your house and they Dublin 12 Ireland have to supply a broadband modem for you, back in at their server. So how

    can they sell you the service for ?20 - ?30 a month? Well the big connection they put in is not just for you. You share it. The number of clients it is shared

    amongst is called ‘the contention ratio’. Eircom advertise a contention ratio of

    48:1 which means you could be sharing it with up to 48 other people. This is

    bad for you and good for Eircom. For example 48 people at ?20 month for a minimum 12 month contract = ?11,520 per year per connection. Now you can

    see why they share it.

Generally, however, not everybody uses the connection at the same time so the

    ISP gets away with it. At peak times though, like around 6 pm when everyone

    gets home from work, your 2Mbps connection can go down to 42 Kbps, slower

    than dialup!

It is sensible to check the contention ratio before buying. Ideally you want a

    combination of download speed and contention ratio which would mean, at worst, no less than 100Kbps. The Clearwire 1Mbps @ 10:1 achieves just this.

    Download Limits

     one There are people operating programs that download lots of information all day.

    If you are sharing with this person, your speed is far more likely to be affected.

    ISPs don’t like this as it makes their connections seem slow, so they impose

    download limits.

Normal users are extremely unlikely exceed these limits. However, people

    downloading movies and MP3’s may do so very quickly. Download limits are enforced in one of two ways.

     The first is billing. If you go over your download limit the ISP may charge you

    (usually a lot) for every kilobyte or megabyte you download. It is quite possible c to be caught out by excess charges of over ?400 per month. Buyers should be clear on what is offered by each ISP.

Other companies, like Clearwire, slow down your connection when you hit your

    limit and speed you back up again the following month. This method saves

    customers a fortune and still makes sure you don’t get contention hogs.

Most ISPs provide some way for you to check your limit for the month. Ring

    their tech support and ask. They have to tell you if they are going to charge



    Company Number: 400703 VAT Registered Number: IE 6420703G Directors: Nick Wheeler, Chris Thomson, Philip Lacey


    + 353 1 4294000 www. 48 Western Parkway Business Park The bane of every computer gamer’s life! Online gaming is not the same as Lower Ballymount Road simple downloading. For example when you fire your photon-torpedo at Zog, Dublin 12 Ireland King of The Potato People, the shot information has to be sent to other players

    via the net. The amount of upload information in a game is almost as large as the download information. If you get a player with a large download but tiny

    upload, it can wreck the game for everyone, while they all wait for information

    to come from his computer. Newer games automatically kick slow players off.

Another example is voice (Skype, Blueface) and video conversations online

    which need to send as much information as you receive. A lag in this type of

    situation means the conversation is broken and unsatisfactory.

    If you’re only surfing, then lag isn’t an issue. If real time interaction is required, then it is.

    Download v Streamed Media

Downloading means capturing information permanently as a file. This could be

    music, film, an airline ticket, anything you can store. Once its on your PC, you

    can access it as often as you like. This is not popular with, for instance, music

    publishers who like you to keep coming back, but don’t want you to share your

    download with anyone else. one

    To overcome this, they use a technology called streaming. This feeds your

    computer little chunks of information one after the other but prevents you from

    recording them. You don’t download the whole movie, just individual chunks.

    You-Tube uses this technology very successfully. You need a fast connection

    with not much lag for successful streaming. One streamed football is about

    700Mb of data. Streaming would to get you up to your download limit very




    Company Number: 400703 VAT Registered Number: IE 6420703G Directors: Nick Wheeler, Chris Thomson, Philip Lacey

    Peer to Peer Networking

    + 353 1 4294000 www. 48 Western Parkway Business Park The original Internet. Lots of little computers sharing with each other. Instead Lower Ballymount Road of downloading a file from one server, imagine a thousand little computers, all Dublin 12 Ireland having the file but sharing little bits of it. This means you don’t need one big

    fast connection into one machine, but the sum of the little ones makes it really


Peer to peer is useful, reliable technology but it has been abused and adapted

    for nefarious purposes and has a bad name in the IT industry. Over 95% of

    P2P content is illegal. The technology isn’t illegal, just the content. MP3’s,

    movies, computer games and computer software can all be shared by

    thousands of home users, all sharing little parts of these files. It is almost

    impossible to police and the cost to legitimate content suppliers is enormous.

ISPs also dislike P2P as it causes the contention to fill up. People run P2P

    software and leave it downloading for days at a time. This is bad news for other

    users of this pipe as well, as it slows the whole lot down.

On the upside of P2P, Skype uses it. The more PCs connected to Skype, the

    better the transmission quality.

ISPs can recognise P2P content and filter it, but they have to block all P2P

    activity, or none of it. With 95% of the content being illegal it is easier for an

    ISP to block it all and ensure that the majority have the best experience one

    possible. Clearwire in Ireland blocks P2P.


VOIP (Voice Over Internet Protocol) allows human conversation between two

    computers but it needs fast up and download speeds. The users voice is

    recorded, squashed and sent to the receiver, and vice-versa. However due to

    small upload speeds the quality is usually not great. Skype (using P2P) is the most popular but there are alternatives. Blueface is VOIP but doesn’t use P2P.

    MSN messenger, AOL Instant Messenger and Yahoo Instant Messenger all c provide VOIP but are not as good as Blueface or Skype. Lag time and higher

    contention means that, at peak times, VOIP can become unusable. This makes

    it unreliable for making calls from home. Business users have other options but

    they are expensive.


    Company Number: 400703 VAT Registered Number: IE 6420703G Directors: Nick Wheeler, Chris Thomson, Philip Lacey

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