Atelier destiné à partager avec mes élèves
(et quiconque veut s'y joindre)
TOUT CE QUI PEUT RENDRE PLAISANT L'APPRENTISSAGE DE L'ANGLAIS ET/OU DU NEERLANDAIS :
funny, leuk, gezellig, aangenaam, enjoyable, agréable, efficace, et tout ce qu'on voudra.
Collection commentée de liens vers des sites intéressants pour le même but.
C'est un des proverbes les plus utilisés en anglais contemporain : "what goes around, comes around". Ca veut dire quelque chose comme "qui sème le vent récolte la tempête". Ou en français d'aujourd'hui : "ce qui t'arrive, tu l'as bien cherché", "tu n'as que ce que tu mérites". C'est même le titre d'un livre sur les proverbes, publié par un chercheur d'une université américaine. Pour en savoir plus cliquer ici. Pour trouver des proverbes (en) anglais, il y des tas de sites. Jetez toujours un coup d'oeil sur Wikiquote. Bien sûr, aujourd'hui tout le monde connait la chanson de Justin Timberlake dont ce proverbe est le titre, et donc je vous la sers sur un plateau d'argent. La vidéo (dont on ne voit que des extraits en général sur les chaines musicales) est l'oeuvre de rien moins que sir Casavetes Junior himself (Nick, le fils de John). Pour les fans de Justin, il a bien entendu son site officiel.
C'est fou ce qu'on apprend à force d'explorer la toile à la recherche de trucs et d'astuces pour rendre son blog attrayant. La puissance du copier-coller ! Comment vous la trouvez ? Plus intéressante pour les textes en anglais, ou ceux en espagnol? Je ne vous donne que les textes en anglais.
Who would have thought That you could hurt me The way you've done it? So deliberate, so determined
And since you have been gone I bite my nails for days and hours And question my own questions on and on
So tell me now, tell me now Why you're so far away When I'm still so close
You don't even know the meaning of the words "I'm sorry" You said you would love me until you die And as far as I know you're still alive, baby You don't even know the meaning of the words "I'm sorry" I'm starting to believe it should be illegal to deceive a woman's heart
I tried so hard to be attentive To all you wanted Always supportive, always patient What did I do wrong? I'm wondering for days and hours It's clear, it isn't here where you belong
Anyhow, anyhow I wish you both all the best I hope you get along
But you don't even know the meaning of the words "I'm sorry" You said you would love me until you die And as far as I know you're still alive, baby You don't even know the meaning of the words "I'm sorry" I'm starting to believe it should be illegal to deceive a woman's heart
You don't even know the meaning of the words "I'm sorry" You said you would love me until you die And as far as I know you're still alive, baby You don't even know the meaning of the words "I'm sorry" I'm starting to believe it should be illegal to deceive a woman's heart
Open heart Open heart It should be illegal to deceive a woman's heart
Open heart Open heart It should be illegal to deceive a woman's heart
The One
So I find a reason to shave my legs Each single morning So I count on someone on Friday nights To take me dancing again To church on Sundays To plant more trees And someday think of kids Or maybe just save a little money
[Refrain] : You're the one I need The way back home is always long But if you're close to me I'm holding on You're the one I need My real life has just begun Cause there's nothing like your smile made of sun
In the world full of strangers You're the one I know
So I learned to cook and finally lose My kitchen phobia And so I got the arms to cuddle in When there's a ghost or a news That brings insomnia To buy more thongs To write more happy songs It always takes a little help from someone
[Refrain] x2
You're the one I need x2
Youre my (??) real life has just begun
You're the one I need x2
Nothing like your smile made of sun
Nothing like your love x3
Whenever, wherever
Lucky you were born that far away so So we could both make fun of distance Lucky that I love a foreign land for The lucky fact of your existence Baby I would climb the Andes solely To count the freckles on your body Never could imagine there were only Too many ways to love somebody
Lo ro lo le lo le Lo ro lo le lo le Can't you see...I'm at your feet
[Refrain] : Whenever, wherever We're meant to be together I'll be there and you'll be near And that's the deal my dear They're over, you're under You'll never have to wonder We can always play by ear But that's the deal my dear
Lucky that my lips not only mumble They spill kisses like a fountain Lucky that my breasts are small and humble So you don't confuse them with mountains Lucky I have strong legs like my mother To run for cover when I need it And these two eyes are for no other The day you leave we'll cry a river
Lo ro lo le lo le Lo ro lo le lo le At your feet...I'm at your feet
[Refrain]
Lo ro lo le lo le Lo ro lo le lo le
sink or fly, say it again
Lo ro lo le lo le lo le
Tell me one more time That you'll live Lost in my eyes
[Refrain] x2
Underneath your clothes
You're a song Written by The hands of God Don't get me wrong This might sound To you a bit odd But you're the place Where all my thoughts Go hiding Right under your clothes Is where I'll find them
Underneath your clothes There's an endless story There's the man I chose There's my territory And of all the things I deserve For being such A good girl honey
Because of you I forgot the Smart ways to rhyme Because of you I'm running out of Reasons to cry When the friends are gone When the party's over We'll still belong To each other
Underneath your clothes There's an endless story There's the man I chose There's my territory And of all the things I deserve For being such A good girl honey
Poem To A Horse
You're to far to bring you close And too high to see below just hangin' on your daily dose I know you never needed anyone But the rolling papers for your grass How can you give what you don't have?
You keep on aiming for the top And quit before you sweat a drop Feed your empty brain with your hydroponic pot You start out playing with yourself You get more fun within your shell Nice to meet you but I gotta go my way
[Chorus:] I'll leave again Cuz I've been waiting in vain But you're so in love with yourself If I say my heart is sore Sounds like a cheap metaphor So I won't repeat it no more
I'd rather eat my soup with a fork Or drive a cab in New York Cuz to talk to you is harder work So what's the point of wasting all my words If it's just the same or even worse Than reading poems to a horse
You keep on aiming for the top And quit before you sweat a drop Feed your empty brain with your hydroponic pot I bet you'll find someone like you Cuz there's a foot for every shoe I wish you luck but I've got other things to do
I'll leave again 'cause I've Been waiting in vain But you're so in love with yourself If I say my heart is sore Sounds like a cheap metaphor So I won't repeat it no more
Hips don't lie
Ladies up in here tonight No fighting We are the Refugees No fighting No fighting Shakira, Shakira
Never really knew that she could dance like this She make a man wanna speak Spanish Como se llama? Si Bonita? Si Mi casa? Su casa? Shakira, Shakira
Oh baby, when you talk like that You make a woman go mad So be wise and keep on reading the signs of my body
[Répétition] : I'm on tonight, you know my hips don't lie I'm starting to feel it's right All the attraction, attention Don't you see baby, this is perfection
Hey girl, I can see your body moving And it's driving me crazy And I didn't have the slightest idea Until I saw you dancing
And when you walk up on the dance floor Nobody could not ignore The way you move your body Just move And everything's so unexpected The way you are connected So you can keep on shaking it
Never knew she could dance like this She make a man wanna speak Spanish Como se llama? Si Bonita? Si Mi casa? Su casa? Shakira, Shakira
Oh baby, when you talk like that You make a woman go mad So be wise and keep on reading the signs of my body
I'm on tonight, you know my hips don't lie I'm starting to feel you boy Come on let's go, real slow Don't you see babe, asi es perfecto
[Répétition]
Shakira, Shakira
Boy, I can see your body moving Half-animal, half-man I don't, don't really know what I'm doing But you seem to have a plan
I will self-restrain Have come to feel me, feel me See I'm doing what I can, but I can't so, you know That's too hard to explain
Baila en la calle de noche, baila en la calle de dia x2
Never really knew that she could dance like this She make a man wanna speak Spanish Como se llama? Si Bonita? Si Mi casa? Su casa? Shakira, Shakira
Oh baby, when you talk like that You know you got me hypnotised So be wise and keep on reading the signs of my body
Senorita, ??? Let me see you move like you going for Colombian Yeah, oh, yeah Sing it, sing it
Mira en barranquilla se baila asi x2
Yeah, she's so sexy, yeah you my fantasy Refugee get back with the Fugees From a third-world country I go back like with ?? cream For humpty hump We need a whole club, Jay-Z Nobody see I ain't what I watch The Colombian's a hitch I ain't guilty, it's a musical transaction Boo-boop-so-boop, no more dooby snack groups Refugees run the scenes ‘cause we own our own booths
I'm on tonight, my hips don't lie I'm starting to feel you boy Come on let's go, real slow Baby, like this is perfecto
Oh, you know I'm on tonight, my hips don't lie I'm starting to feel it's right
The attraction, attention Baby, like this is perfection
No fighting x2 Don't Bother
She’s got the kind of look that defies gravity She’s the greatest cook And she’s fat free
She’s been to private school And she speaks perfect French She’s got the perfect friends Oh isn’t she cool
She pratices Tai Chi She’d never lose her nerve She’s more than you deserve She’s just far better than me
Hey hey
[Répétition] : So don’t bother I won’t die of deception I promise you won’t ever see me cry Don’t feel sorry
And don't bother I’ll be fine But she’s waiting The ring you gave to her will lose its shine So don’t bother, be unkind
I’m sure she doesn’t know How to touch you like I would I beat her at that one good Don’t you think so?
She’s almost 6 feet tall She must think I’m a flea I’m really a cat you see And it’s not my last life at all
Hey hey
[Répétition]
Don’t bother I’ll be fine But she’s waiting The ring you gave to her will lose its shine So don’t bother, be unkind
For you, I’d give up all I own And move to a communist country If you came with me, of course And I’d file my nails so they don’t hurt you And lose those pounds, and learn about football If it made you stay, but you won’t, but you won’t
So don’t bother, I’ll be fine, I’ll be fine, I’ll be fine, I’ll be fine Promise you won’t ever see me cry
And after all I’m glad that I’m not your type Promise you won’t ever see me cry
So don’t bother, I’ll be fine, I’ll be fine, I’ll be fine, I’ll be fine Promise you won’t ever see me cry
And after all I’m glad that I’m not your type Promise you won’t ever see me cry
Excellent choix! Je félicite celui qui a choisi cet article de How stuff works. Voilà une excellente façon d'apprendre (ou de réviser) le vocabulaire essentiel. Pour les autres, je reprends l'article (je sais, c'est pas bien, mais je cite les sources, et c'est pour vous permettre d'utiliser, une fois encore Alexandria). Les vidéos sont super intéressantes aussi !
Have you ever thought about building your own computer? Actually buying a motherboard and a case along with all the supporting components and assembling the whole thing yourself?
Here are three reasons why you might want to consider taking the plunge:
You will be able to create a custom machine that exactly matches your needs.
It will be much easier to upgrade your machine in the future because you will understand it completely.
You may be able to save some money.
And, if you have never done it before, you will definitely learn a lot about computers.
In this article, we'll take you through the entire process of building a computer. You'll learn how to choose the parts you will use, how to buy them and how to put them all together. When you're done, you will have exactly the machine that you need. Let's get started.
Decisions, Decisions
Where do we start? Actually putting the machine together is pretty easy, but picking the parts and buying them takes research.
The first step in building a computer is deciding what type of machine you want to build. Do you want a really inexpensive computer for the kids to use? A small, quiet machine to use as a media computer in the living room? A high-end gaming computer? Or maybe you need a powerful machine with a lot of disk space for video editing. The possibilities are endless, and the type of machine you want to build will control many of the decisions you make down the line. Therefore, it is important to know exactly what you want the machine to accomplish from the start.
Let's imagine that you want to build a powerful video editing computer. You want it to have a dual-core CPU, lots of RAM and a terabyte of disk space. You also want to have FireWire connectors on the motherboard. These requirements are going to cause you to look for a motherboard that supports:
FireWire connections (possibly in both the front and back of the case)
Then it all needs to go in a case with enough space to hold multiple hard disks and enough air flow to keep everything cool.
With any computer you build, knowing the type of machine you want to create can really help with decision-making.
The Motherboard's the Thing Choosing a motherboard is the most interesting part of any building project. The reason it is so interesting is because there are hundreds of motherboards to choose from and each has its own advantages and disadvantages.
One easy way to think about motherboards is to break them up into a few categories. For example:
Cheap motherboards: Generally in the $50 range, these are motherboards for older CPUs. They are great for building inexpensive machines.
Middle-of-the-road motherboards: Ranging in price from $50 to $100, these are one step up from the cheap motherboards. In many cases you can find motherboard and CPU combos in this price range, which is another great way to build a cheap machine or an inexpensive home/office computer.
A middle-of-the-road motherboard
High-end motherboards: If you are building a powerful gaming machine or video workstation, these motherboards give you the speed you need. They range in price from $100 to $200. They handle the latest CPU chips at their highest speeds.
Extreme motherboards: Falling into the over-$200 range, these motherboards have special features that boost the price. For example, they might have multiple CPU sockets, extra memory slots or special cooling features.
You need to decide whether you are building a "cheap machine," a "high-end machine" or a "tricked-out super machine" and then choose your motherboard accordingly. Here are some other decisions that help narrow down your motherboard choices:
Do you want to use an Intel or an AMD processor? Making this choice will cut the number of motherboards in half. AMD chips are often cheaper, but lots of people are die-hard Intel fans.
What size motherboard do you want to use? If you are trying to build a smaller computer, you may want to look at micro ATX cases. That means you will need to buy a micro ATX motherboard. Otherwise you can use a normal ATX motherboard and case. (There are also smaller motherboard form factors like mini-ITX and even nano-ITX if you want to go really small.)
How many USB ports do you want? If you want several, make sure the motherboard can handle it.
Do you need FireWire? It's nice if the motherboard handles it (although it is also possible to add a card).
Do you want an AGP or PCI Express graphics card? Or do you want to use a graphics card on the motherboard to keep the price and size down? If you want to go the cheapest route, make sure the motherboard includes a video card on-board (easiest way to tell is to see if there is a DVI or VGA connector on the motherboard). PCI Express is the latest/greatest thing, but if you want to re-use an AGP card you already own, that might be a reason to go with AGP.
Do you want to use PATA (aka IDE) or SATA hard disks? SATA is the latest thing, and the cables are much smaller.
What pin configuration are you using for the CPU? If you want to use the latest CPUs, make sure that your motherboard will accept them.
Do you want to try things like dual video cards or special high-speed RAM configurations? If so, make sure the motherboard supports it.
If you don't care about any of this stuff (or if it all sounds like gibberish to you), then you're probably interested in building a cheap machine. In that case, find an inexpensive motherboard/CPU combo kit and don't worry about all of these details.
...And the Rest Once you have chosen your motherboard, you are ready to choose everything else. Here's what you need to get:
The CPU that's the right brand and the right pin configuration to fit your motherboard. Pick whichever CPU clock speed fits your budget and intentions. (If you purchase a motherboard/CPU combo, you can skip this step.)
The RAM with the correct pin configuration that will match your motherboard. If your motherboard is using a specialty RAM configuration (normally to improve performance), make sure the RAM you buy matches its requirements.
If the case does not come with a power supply, you'll need to choose one. Make sure its connectors match the motherboard. Three hundred watts are enough for most machines, but if you are building a gaming machine with multiple video cards or a machine with lots of disks, you may want to consider something bigger.
Choose a video card if you are not using the onboard video on the motherboard. Make sure the card's connector is appropriate for the motherboard (AGP or PCI Express).
A basic AGP-based graphics card
Choose an optical drive. If you are building a cheap machine, get the cheapest CD-ROM drive you can find. If you want to burn DVDs and CDs, make sure the drive can handle it.
Choose a hard disk, making sure that it matches the PATA/SATA status of your motherboard.
Choose an operating system: Windows XP (which comes in home, professional and media center editions) or Linux in its hundreds of different forms.
Buying Now that you have picked everything out, it is time to purchase your parts. You have three options:
Mail order on the Internet - All kinds of stores sell computer parts on the Web. Visit a place like HowStuffWorks Shopper to compare prices. Don't forget about eBay.
A big national chain - Places like Tiger Direct, Fry's, and CompUSA have stores in most large cities that will sell you parts. They also have people on staff who may be able to answer questions.
local parts retailer - Any big city will have a number of smaller, local shops selling parts. Look in the Yellow Pages or online. I live in Raleigh, N.C., and a typical shop of this genre in Raleigh is called Intrex. The people working at a shop like this can often answer lots of questions, and they may also be willing to help you if your machine does not work after you assemble it.
Now that you have your parts, it is time to build. This is the fun part.
Building
But before we start building, we need to say one thing about static electricity. Most of the parts you will be handling when you assemble your computer are highly sensitive to static shocks. What that means is that if you build up static electricity on your body and a shock passes from your body to something like a CPU chip, that CPU chip is dead. You will have to buy another one.
The way you eliminate static electricity is by grounding yourself. There are lots of ways to ground yourself, but probably the easiest is to wear a grounding bracelet on your wrist. Then you connect the bracelet to something grounded (like a copper pipe or the center screw on a wall outlet's face plate). By connecting yourself to ground, you eliminate the possibility of static shock.
Each combination of parts is unique. But in general, here are the basic steps you will need to follow when you assemble your machine.
Installing the Microprocessor and RAM First, you'll need to unwrap the motherboard and the microprocessor chip. The chip will have one marked corner that aligns with another marked corner of its socket on the motherboard. Align the corners and drop the microprocessor into the socket. You don't need to apply any pressure – if it's aligned correctly, it should fall into place. Once you have it in, cinch it down with the lever arm.
Now, you need to install the heat sink. The CPU box will contain a manual that tells you how to do it. The heat sink will contain either a heat sink sticker or heat sink grease to use when mounting the heat sink on the CPU. Follow the instructions closely to install it. To install our heat sink, all we had to do was put it in place, cinch it down with flanges on either side and lock it with a cam. Connect the power lead for the heat sink to the motherboard.
Next, you'll install the RAM. Look on the motherboard for the slot marked "one" and firmly press the RAM module into it. It will probably take more pressure than you'd think to get the RAM into place. Each side of the module should also have a rotating arm that will lock the RAM down.
Now your motherboard is ready to put in the case.
Assembling the Case Next, you'll assemble the case. You'll need to install the power supply, the motherboard, a faceplate and standoffs to hold the motherboard in place. You'll also need to connect some wires to the motherboard.
Your motherboard should have come with a face plate for its back connectors. The case already has a hole cut in it for the plate, so you just need to put in the plate and press it until it clicks into place. Now you can put in in the motherboard. It needs to sit about a quarter of an inch away from the case's surface so that none of its connectors touch the case. You'll accomplish this by placing spacers, which are also included with the motherboard.
Because each motherboard is different, you'll have to set it into the case first to see which screw holes on the motherboard match up with the pre-drilled holes in the case. Then you can take the motherboard back out, place the spacers, and put the motherboard in on top of them. Make sure that the motherboard lines up with the faceplate and the holes line up with the spacers.
Find the screws that fit (these should have come with the case) the spacers and screw down the motherboard. Don't screw them in too tightly -- they just need to be in snugly. Be very careful when putting in the screws. If you drop them into the case, they could damage the fine wires on the motherboard.
Installing the power supply.
Now you can install the power supply in the case if it's not already installed. The power supply has two sides. The fan side faces outside the case and the wire side faces inside. Slide the power supply onto its brackets and secure it with screws (the case or the power supply should have come with them).
Connect the power leads to the motherboard. There should be a large one and a small one, and it will be obvious as to where each one goes.
You'll be left with about 15 more wires. Don't worry -- the manual has a page to tell you exactly where each one goes. Each of them has a label that corresponds to a label on the correct port.
Installing the Hard Drive, CD-ROM and Video Card The last steps are installing the hard drive and the CD-ROM drive. The case has a removable bracket with four rubber grommets on it, which line up with four holes on the hard drive. It also came with four screws made just to punch through those grommets. Screw the hard drive into the bracket, then put the bracket back into its slot in the case. If you are using IDE/PATA drives, be sure to set the jumpers correctly. Then connect the hard disk to the power using one of the connectors coming off of the power supply. If it fits, then it's a match.
Now install the cables. One side of the cable has a red stripe on it, which makes it " pin 1." Look on the motherboard and hook the cable into the IDE connector marked "1." Insert the other end of the cable on the back of the drive. Now the drive is ready to go.
Install the CD-ROM drive next. Again, set the jumpers correctly. The drive fits in the front of the case, and you may have to pop out a faceplate to make room for it. Slide it in and screw it into place, making sure that it's aligned with the front of the case. Just as with the hard drive, you can use any available connector from the power supply. You'll also use the cable that came with the CD-ROM drive to connect it to the motherboard (align the red stripe for "pin 1") and plug the other end into the drive. Connect the audio for the CD drive. Again, there's an obvious place for it to plug in on the motherboard and on the drive itself.
Placing the hard drive into its bracket.
If you're using a video card, now you'll install it as well. Our motherboard has an AGP video slot so we have an AGP video card. The motherboard only has one video card slot, so you should be able to find it easily (you can also use the manual). Line up the card with the slot and push it into place. If the video card has its own power connector, connect it to the power supply. If the case has extra fans, make sure they have power too.
Now you can close up the case and add a monitor, keyboard, mouse and speakers. In the next section, we'll cover what to do after powering up the computer and what steps to follow if it doesn't work.
Powering Up and Troubleshooting
Now, the moment of truth -- it's time to turn your machine on and see if it works. If there's a switch on the back of the power supply, make sure it is on. Also make sure that the power supply is set correctly to 110 or 220 volts (some power supplies do this automatically, others have a switch or a slider).
Then push the power switch on the front of the case. In the ideal case, four things will happen:
You will see/hear the fans spin up
You will hear the hard disk spin up.
Lights will light on the case.
You will see something happening on the monitor to indicate that the motherboard is alive.
If you see/hear all of that happening, you are successful. You have created a working machine. Using the manual that came with the motherboard you can enter the BIOS screens and make sure everything looks OK. Chances are you will need to set the machine's date/time, but that is probably all you have to do. Everything else is probably automatic. All the drives will be recognized and auto-configured. The default settings on the motherboard will be fine.
The next step is to install the operating system. And presto, you have a working machine of your own creation. Congratulations!
Troubleshooting What if you put it all together and it doesn't work? This is the one possible downside of building your own machine. It is hard to describe the feeling you get when you try turning on the machine and nothing happens. You have put in several hours of work and a significant amount of cash, so it's discouraging to get no response.
All is not lost, however. Here are several items to check:
Is the power supply firmly plugged in and turned on (many power supplies have a small switch on the back)? Try a different outlet.
Did you plug the power supply into the motherboard? Look at the manual for details.
Make sure that your motherboard is connected to the power supply.
Is the case's power switch properly connected to the motherboard? If you have plugged the switch into the wrong pins on the motherboard, it will not work. Check the motherboard manual.
Are the drives connected to the motherboard properly? Do they have power?
Unseat and reseat the video card. If the motherboard has onboard video, try to remove the video card completely and boot using the onboard version.
If you have checked all of that and nothing continues to happen, it could mean:
The power supply is bad
The switch on the case doesn't work. We actually had this happen once on a machine we built at HowStuffWorks.
Something is wrong with the motherboard or the CPU.
The easiest way to determine where the problem lies is to swap parts. Try a different power supply. Swap a different motherboard into the case. Play around with different combinations.
If it is still not working, then you have a few options at this point. You can go back to the shop that sold you the parts. If you bought them from a small local shop, they can help you debug the problem (although it may cost you). If they sold you a bad motherboard (rare, but possible) they will usually help you out. You can also try to find a more experienced builder who would be willing to help you. There is a rational cause for the problem you are experiencing -- either a bad part or a bad connection somewhere -- and you will find it.
Now that you've seen how simple it is to build your own computer, we hope that you'll give it a shot. You'll have a computer that you understand completely and will be easy to upgrade. You can save money, and it's a lot of fun too. So the next time you need a new computer, consider building it yourself!
For lots more information about computer parts, check out the links on the next page.
If you have been using the Internet for any length of time, and especially if you work at a larger company and browse the Web while you are at work, you have probably heard the term firewall used. For example, you often hear people in companies say things like, "I can't use that site because they won't let it through the firewall."
If you have a fast Internet connection into your home (either a DSL connection or a cable modem), you may have found yourself hearing about firewalls for your home network as well. It turns out that a small home network has many of the same security issues that a large corporate network does. You can use a firewall to protect your home network and family from offensive Web sites and potential hackers.
Basically, a firewall is a barrier to keep destructive forces away from your property. In fact, that's why its called a firewall. Its job is similar to a physical firewall that keeps a fire from spreading from one area to the next. As you read through this article, you will learn more about firewalls, how they work and what kinds of threats they can protect you from.
What It Does
A firewall is simply a program or hardware device that filters the information coming through the Internet connection into your private network or computer system. If an incoming packet of information is flagged by the filters, it is not allowed through.
If you have read the article How Web Servers Work, then you know a good bit about how data moves on the Internet, and you can easily see how a firewall helps protect computers inside a large company. Let's say that you work at a company with 500 employees. The company will therefore have hundreds of computers that all have network cards connecting them together. In addition, the company will have one or more connections to the Internet through something like T1 or T3 lines. Without a firewall in place, all of those hundreds of computers are directly accessible to anyone on the Internet. A person who knows what he or she is doing can probe those computers, try to make FTP connections to them, try to make telnet connections to them and so on. If one employee makes a mistake and leaves a security hole, hackers can get to the machine and exploit the hole.
With a firewall in place, the landscape is much different. A company will place a firewall at every connection to the Internet (for example, at every T1 line coming into the company). The firewall can implement security rules. For example, one of the security rules inside the company might be:
Out of the 500 computers inside this company, only one of them is permitted to receive public FTP traffic. Allow FTP connections only to that one computer and prevent them on all others.
A company can set up rules like this for FTP servers, Web servers, Telnet servers and so on. In addition, the company can control how employees connect to Web sites, whether files are allowed to leave the company over the network and so on. A firewall gives a company tremendous control over how people use the network.
Firewalls use one or more of three methods to control traffic flowing in and out of the network:
Packet filtering - Packets (small chunks of data) are analyzed against a set of filters. Packets that make it through the filters are sent to the requesting system and all others are discarded.
Proxy service - Information from the Internet is retrieved by the firewall and then sent to the requesting system and vice versa.
Stateful inspection - A newer method that doesn't examine the contents of each packet but instead compares certain key parts of the packet to a database of trusted information. Information traveling from inside the firewall to the outside is monitored for specific defining characteristics, then incoming information is compared to these characteristics. If the comparison yields a reasonable match, the information is allowed through. Otherwise it is discarded.
Making the Firewall Fit
Firewalls are customizable. This means that you can add or remove filters based on several conditions. Some of these are:
IP addresses - Each machine on the Internet is assigned a unique address called an IP address. IP addresses are 32-bit numbers, normally expressed as four "octets" in a "dotted decimal number." A typical IP address looks like this: 216.27.61.137. For example, if a certain IP address outside the company is reading too many files from a server, the firewall can block all traffic to or from that IP address.
Domain names - Because it is hard to remember the string of numbers that make up an IP address, and because IP addresses sometimes need to change, all servers on the Internet also have human-readable names, called domain names. For example, it is easier for most of us to remember www.howstuffworks.com than it is to remember 216.27.61.137. A company might block all access to certain domain names, or allow access only to specific domain names.
Protocols - The protocol is the pre-defined way that someone who wants to use a service talks with that service. The "someone" could be a person, but more often it is a computer program like a Web browser. Protocols are often text, and simply describe how the client and server will have their conversation. The http in the Web's protocol. Some common protocols that you can set firewall filters for include:
IP (Internet Protocol) - the main delivery system for information over the Internet
TCP (Transmission Control Protocol) - used to break apart and rebuild information that travels over the Internet
HTTP (Hyper Text Transfer Protocol) - used for Web pages
FTP (File Transfer Protocol) - used to download and upload files
UDP (User Datagram Protocol) - used for information that requires no response, such as streaming audio and video
ICMP (Internet Control Message Protocol) - used by a router to exchange the information with other routers
SMTP (Simple Mail Transport Protocol) - used to send text-based information (e-mail)
SNMP (Simple Network Management Protocol) - used to collect system information from a remote computer
Telnet - used to perform commands on a remote computer
A company might set up only one or two machines to handle a specific protocol and ban that protocol on all other machines.
Ports - Any server machine makes its services available to the Internet using numbered ports, one for each service that is available on the server (see How Web Servers Work for details). For example, if a server machine is running a Web (HTTP) server and an FTP server, the Web server would typically be available on port 80, and the FTP server would be available on port 21. A company might block port 21 access on all machines but one inside the company.
Specific words and phrases - This can be anything. The firewall will sniff (search through) each packet of information for an exact match of the text listed in the filter. For example, you could instruct the firewall to block any packet with the word "X-rated" in it. The key here is that it has to be an exact match. The "X-rated" filter would not catch "X rated" (no hyphen). But you can include as many words, phrases and variations of them as you need.
Some operating systems come with a firewall built in. Otherwise, a software firewall can be installed on the computer in your home that has an Internet connection. This computer is considered a gateway because it provides the only point of access between your home network and the Internet.
With a hardware firewall, the firewall unit itself is normally the gateway. A good example is the Linksys Cable/DSL router. It has a built-in Ethernet card and hub. Computers in your home network connect to the router, which in turn is connected to either a cable or DSL modem. You configure the router via a Web-based interface that you reach through the browser on your computer. You can then set any filters or additional information.
Hardware firewalls are incredibly secure and not very expensive. Home versions that include a router, firewall and Ethernet hub for broadband connections can be found for well under $100.
What It Protects You From
There are many creative ways that unscrupulous people use to access or abuse unprotected computers:
Remote login - When someone is able to connect to your computer and control it in some form. This can range from being able to view or access your files to actually running programs on your computer.
Application backdoors - Some programs have special features that allow for remote access. Others contain bugs that provide a backdoor, or hidden access, that provides some level of control of the program.
SMTP session hijacking - SMTP is the most common method of sending e-mail over the Internet. By gaining access to a list of e-mail addresses, a person can send unsolicited junk e-mail (spam) to thousands of users. This is done quite often by redirecting the e-mail through the SMTP server of an unsuspecting host, making the actual sender of the spam difficult to trace.
Operating system bugs - Like applications, some operating systems have backdoors. Others provide remote access with insufficient security controls or have bugs that an experienced hacker can take advantage of.
Denial of service - You have probably heard this phrase used in news reports on the attacks on major Web sites. This type of attack is nearly impossible to counter. What happens is that the hacker sends a request to the server to connect to it. When the server responds with an acknowledgement and tries to establish a session, it cannot find the system that made the request. By inundating a server with these unanswerable session requests, a hacker causes the server to slow to a crawl or eventually crash.
E-mail bombs - An e-mail bomb is usually a personal attack. Someone sends you the same e-mail hundreds or thousands of times until your e-mail system cannot accept any more messages.
Macros - To simplify complicated procedures, many applications allow you to create a script of commands that the application can run. This script is known as a macro. Hackers have taken advantage of this to create their own macros that, depending on the application, can destroy your data or crash your computer.
Viruses - Probably the most well-known threat is computer viruses. A virus is a small program that can copy itself to other computers. This way it can spread quickly from one system to the next. Viruses range from harmless messages to erasing all of your data.
Spam - Typically harmless but always annoying, spam is the electronic equivalent of junk mail. Spam can be dangerous though. Quite often it contains links to Web sites. Be careful of clicking on these because you may accidentally accept a cookie that provides a backdoor to your computer.
Redirect bombs - Hackers can use ICMP to change (redirect) the path information takes by sending it to a different router. This is one of the ways that a denial of service attack is set up.
Source routing - In most cases, the path a packet travels over the Internet (or any other network) is determined by the routers along that path. But the source providing the packet can arbitrarily specify the route that the packet should travel. Hackers sometimes take advantage of this to make information appear to come from a trusted source or even from inside the network! Most firewall products disable source routing by default.
Some of the items in the list above are hard, if not impossible, to filter using a firewall. While some firewalls offer virus protection, it is worth the investment to install anti-virus software on each computer. And, even though it is annoying, some spam is going to get through your firewall as long as you accept e-mail.
The level of security you establish will determine how many of these threats can be stopped by your firewall. The highest level of security would be to simply block everything. Obviously that defeats the purpose of having an Internet connection. But a common rule of thumb is to block everything, then begin to select what types of traffic you will allow. You can also restrict traffic that travels through the firewall so that only certain types of information, such as e-mail, can get through. This is a good rule for businesses that have an experienced network administrator that understands what the needs are and knows exactly what traffic to allow through. For most of us, it is probably better to work with the defaults provided by the firewall developer unless there is a specific reason to change it.
One of the best things about a firewall from a security standpoint is that it stops anyone on the outside from logging onto a computer in your private network. While this is a big deal for businesses, most home networks will probably not be threatened in this manner. Still, putting a firewall in place provides some peace of mind.
Proxy Servers and DMZ
A function that is often combined with a firewall is a proxy server. The proxy server is used to access Web pages by the other computers. When another computer requests a Web page, it is retrieved by the proxy server and then sent to the requesting computer. The net effect of this action is that the remote computer hosting the Web page never comes into direct contact with anything on your home network, other than the proxy server.
Proxy servers can also make your Internet access work more efficiently. If you access a page on a Web site, it is cached (stored) on the proxy server. This means that the next time you go back to that page, it normally doesn't have to load again from the Web site. Instead it loads instantaneously from the proxy server.
There are times that you may want remote users to have access to items on your network. Some examples are:
Web site
Online business
FTP download and upload area
In cases like this, you may want to create a DMZ (Demilitarized Zone). Although this sounds pretty serious, it really is just an area that is outside the firewall. Think of DMZ as the front yard of your house. It belongs to you and you may put some things there, but you would put anything valuable inside the house where it can be properly secured.
Setting up a DMZ is very easy. If you have multiple computers, you can choose to simply place one of the computers between the Internet connection and the firewall. Most of the software firewalls available will allow you to designate a directory on the gateway computer as a DMZ.
Once you have a firewall in place, you should test it. A great way to do this is to go to www.grc.com and try their free Shields Up! security test. You will get immediate feedback on just how secure your system is!
For more information on firewalls and related topics, check out the links on the next page.
Profitons donc de Alexandria pour réviser tout le vocabulaire du niveau de base de la méthode English in Mind. Voici la liste complète des mots et expressions à connaître pour l'examen de fin d'année. Ils sont par ordre alphabétique par chapitre. Une hésitation : il vous suffit de double cliquer sur le mot pour voir apparaître une fenêtre avec soit la définition du mot en anglais, soit la traduction en français, et dans le meilleur des cas, une série d'expressions où ce mot apparait sur laquelle il suffit de cliquer à nouveau (une seule fois) pour voir l'article du dictionnaire qui y est relié apparaitre dans la fenêtre.
Alexandria
1. answer bad big board book boring can cassette CD chair cheap cinema city computer computer game correct desk door excellent expensive film football football team from good hamburger homework hotel I know. I can help you. I don't understand. in interesting know man men message museum name new No problem. notebook old on open page pen pencil people person phone pizza read restaurant sandwich singer small Sorry, I don't know. taxi teacher Thanks. That's correct. TV video what What's the answer? window woman women Yes, great. 2.actor address American Australian be be be be Belgian Belgium best friend Brazil Brazilian Britain British Canada China Chinese England English father film star flag footballer French friend Germany girl golfer great hero heroine How (old) Irish Italian Italy Japan mobile phone model mother Norway player Poland Polish Portugal right Russia school Spain Spanish star Swedish Switzerland tennis think think Turkey Turkish where who winner 3. about at awful band brother capital car cat chocolate classical coffee come concert dog fantastic favourite go Guess what? horse How (many) I want to go. jam Let's go together. like love lucky music of Of course play pop group popular rap say see song speaker sport terrible volleyball want What about you? with wonderful 4. air aunt bank bicycle cartoon children colour TV cousin dad daughter dead dishwasher drink famous finish garden get give go for a walk go shopping grandfather grandmother grandparent happy have have a fight hobby hospital house job learn letter listen live live look after magic mum newspaper north nurse parent part time road same sell shop sister son south speak stop street market study supermarket sweet teenager to be called town typical uncle unhappy washing machine watch weekend wife wizard work work write writer 5. Are you sure? around ask beautiful behind between biology bookshop building buy café catch change chemist city centre clothes collection different dinosaur directions do down excuse (me) fashionable flight food happen high street history hour I have no idea. idea in front of into leader library look at magazine milk minute money natural newsagent next to opinion parcel park park pay post office railway station river boat send shampoo shoe sight sit stamp start stupid take tour tourist travel card trip try turn underground line university visit wait Wait a minute. world young You're welcome. 6. age arm banana bed beige black blonde blue break brown budgie chimpanzee Christmas collar curly dark destroy DNA drive DVD player ear electrical equipment exotic eye face fair finger first name foot forest glasses good-looking green grey guinea-pig hair hairstyle hamster hand have got home intelligent lead leg little lizard long luxury medium-length membership form mouth nice nose opposite orange owner pink practical practice purple rabbit red repeat short similar smile snake spend spider stereo straight surname thumb use verb video store wavy wear white why wrong yellow 7. alligator apple arrive beef bread breakfast burger bus carrot cheese chicken chips cola day delicious dessert disgusting Do you think so? drink eat egg exercise fast food place fresh fruit grape grasshopper grocery hardly ever hate honey hungry ice cream I'm really hungry. juice kangaroo kilo lamb lasagne lemonade lettuce lovely lunchtime main course mayonnaise meal meat menu month mousse mushroom mustard onion orange order pâté pie potato rattlesnake ready Really? rice roast lamb salad salt selection snail soup special starter stay steak strange strawberry sugar tea tell toast tomato true vegetable vinegar waiter water What's wrong? 8. always chat show check comedy comedy programme dance dinner documentary electricity email evening every day / week / month / year farm fish Friday funny game show get up go swimming interview kilometre lesson lunch Monday never often once a day / week / month / year radio Saturday school programme simple sing soap opera sometimes sports programme Sunday talk the news Thursday traditional Tuesday twice a day / week / month / year usually Wednesday 9. alone angry bored boyfriend call close confused contact cry excited fancy feel final fine forget fun girlfriend go away grass Hang on (a minute). hear heart holiday I miss (San Francisco). join late laugh leave mail match miss mom need night noise sad scared She's fine. shout sleep sound team test walk What's the matter? worried 10. against American football basketball bike boat camel cerebral palsy cold count cricket cycle cycling draw Europe fact find out free front guitar gymnastics hockey hop juggle lie local member netball outside oxygen PE (physical education) piano pull push quite race riding rollerblading roof rugby run running sea seat second seem ski snowboard soccer sports hall student support survey swim swimming take part triathlon under violin well wet wheelchair win winter worm 11. armchair babysit ball bath bathroom beach bedroom clean cloudy Come round to my place. cooker dining room flat fridge hall have a good/great time hope I'm on my way. kitchen living room make Maths milkshake Nothing much. party rain See you (soon). shower sofa sun sunny swimming pool table take a picture teeth (plural of tooth) toilet warm weather What are you up to? 12. April attraction August autumn balloon birthday carnival colourful corner costume dancing December DJ dress enjoy February festival float ghost Halloween hat huge important include into jacket January jazz July June knock lamp large letterbox March May national November October onto parade party personal stereo pumpkin put scarf September skirt sound system spring steel band stone street stall summer sweater Thanksgiving through trainers treat trick trousers try on turkey witch year 13. 10th (tenth) 11th (eleventh) 12th (twelfth) 13th (thirteenth) 1st (first) 20th (twentieth) 2nd (second) 30th (thirtieth) 3rd (third) 4th (fourth) 5th (fifth) 6th (sixth) 7th (seventh) 8th (eighth) 9th (ninth) afternoon apartment building autograph bag Calm down! Can I have a look? gun hard hard hard ill inside last month / night / week / weekend Oh, brilliant! piece of paper pocket police project recording studio shoot sign tomorrow tonight wallet yesterday yesterday afternoon / evening / morning You must be joking! 14. accident apartheid beat beat become blood cathedral clean conditions die dirty doctor end fight go to bed go to school go to the cinema go to work government have a bath/shower have a coffee have an ice cream have breakfast / lunch / dinner lady land language Latin life marriage marry mean medicine moon Olympic Games organisation out play sports play the piano population practise English practise the piano president prison save Science separate shop assistant signal soldier to be born travel vote war 15. angrily begin bring busy captain card careful carefully casino castle coat completely crew cup danger detective novel disappear disappearance early easy empty exam fall find gamble Got a minute? group guide hole iceberg kill lose luck monster mysterious mystery No idea. noisy normally normally on board (the ship) photograph plane present pretty probably quickly quietly real remember rich room ship show silent slow slowly smart steal storm story sudden suddenly tall well 16. activity adult announcement better bigger busier camp canoe chef climb closer club comfortable compare competition cook countryside dance dangerous difficult dream during earn easier escape everyone exciting fast free freer glass golf happier hot hotter island laptop later less longer loudspeaker system modern near noisier non-stop older old-fashioned organise organised outside pool own palm tree paradise perhaps public quiet quieter return safe safer school subject seaside sports facilities subtropical temperature text transport UFO villa village wish worse younger
Vous avez déjà remarqué comme la musique fonctionne comme d'autres secteurs : la mode vestimentaire, la déco et le mobilier. Le principe, c'est qu'on reprend des bribes de ce que les gens ont déjà aimé, il y a environ une génération, et on en refait autre chose. Ce qui est pratique, c'est qu'on accroche immédiatement à cause de ce qu'on reconnait. Sur les radios, pour l'instant, on peut entendre une version actualisée d'un morceau de Supertramp qui s'intitulait "Breakfast in America", sorti en 1979 sur l'album du même nom ('éponyme' on dit sur les radios branchées).
