Welcome to www.felasofi.org
Web Hosting - DNS, How The Internet Keeps Track of Names
The way computers communicate is, in a way, very similar to something very familiar: the postal system that delivers letters and packages. Here's how...
The Internet is just what the name suggests, a large inter-connected set of networks. But those networks are pointless without the one part that forms what is called their 'end-nodes', otherwise known as computers. Those computers often need to share information because the people who use them want to share information.
But, in a system where there are millions of separate computers, how can you enable them all to communicate? One very important feature of that solution is performed by something called DNS, the Domain Name System.
Every part of a network that is going to send or receive information is assigned an IP address. That's a numeric identifier that uniquely specifies a particular 'node', such as a computer, a router that directs traffic or other component. They look like this: 22.214.171.124
But those numbers are more difficult for people to remember and work with. They also aren't very attractive from a marketing perspective. So, a naming system was layered on top of some of them, mostly the computers involved, though routers have names, too.
But once you have a system that associates a unique IP address to a given name, you need some way of keeping track of all of them. That's carried out by several different pieces of the system: Name Registrars, DNS Servers and other components.
The Name Registrars, overseen by IANA (Internet Assigned Numbers Authority) and other international bodies, provide and keep track of domain names. When you register with GoDaddy or any of a hundred other intermediate companies, ultimately that information makes its way into a number of specialized databases stored inside DNS Servers.
A DNS Server is the hardware and/or software that tracks and forwards the IP Address/Domain Name pair from one place to the next. In many cases, there are a number of them between your browser and the remote computer you want to share information with.
Suppose you request information from, say, Yahoo's site by clicking on a link on their site. DNS resolves (translates) the name of WHO IS making the request and OF WHOM, to addresses, then passes the request through the network to the requested IP address. The requested data is then passed back through the mesh of network components to your computer and displayed in your browser.
Whether the communication is between a desktop computer and a server somewhere, or between one server and another, the process is essentially the same. DNS servers translate names into IP addresses and the requests for data are forwarded on.
In some cases those DNS servers are part of a specialized network computer whose sole job is to do the translation and forwarding. In other cases the DNS software may reside on a server that also houses a database of general data, or stores email, or performs other functions.
But however complicated the chain or the parts, the basic process is simple. Translate the name to an address, just as the postal system does. Whether international or local, your name is associated with an address, and the deliveries are made to the address, then forwarded to a particular name.
Evaluating your Free Offers of Stuff Getting free stuff can be a lot of fun, and for many people, the hunt for freebies is as fun as actually enjoying the free products themselves. There is a dark side to freebie offers, however. Many scam artists have come to realize that pretending to offer free things is a great way to trick people into handing over sensitive information about them than can be used in identity theft operations or even bilk them out of cold, hard cash. For that reason, it is important to make sure you know how to stay out there when you?re looking for free offers. There are some things you can do to make sure you freebie hunting only brings you good times ? these common sense rules are a great place to start. You?ve heard it a million times before ? if it sounds too good to be true, it probably is. The reason you have heard it so many times is that it almost holds water. Think about the reason that companies give away free things. They?re usually not doing it for charity. They want you try to their products in the hope that you will come back to them as a paying customer in the future, and they?re doing it to build good will for their company over all. They?re definitely not doing it go broke. So consider whether the freebie offers you come across make sense according to these criteria. Does it make sense that a company will give you a free bag of their new flavor of chips or a trial size jar of their new face cream? Sure it does, because if you like it, you may buy these products in the future. Does it make sense that a company will give you an all expenses paid, two-week first class trip to Bali for you and ten of your friends? Not so much. Don?t waste your time on these too good to be true freebies ? they may end up costing your big time in the long run. By the same token, the more outlandish an offer sounds, the more you have to look for the small print. Sure, maybe the hotel chain is willing to give you a free weekend in their beachfront hotel. The small print in the offer might say that you have to agree to spend 10 hours a day at a sales seminar or that the free weekend is yours after you pay for a two week stay. One particular airline ran an offer for a free coach class plane ticket from New York to London. The small print said you had to buy two, full price first class tickets on that same route before you could get the free on ? at a cost of around $8,000 per ticket. Before you jump, make sure you get all of the details. Freebie offers that actually require you to shell out some money are very tricky. Sometimes they are legitimate ? after all, if you are accustomed to paying full price first class airfare, a free coach class ticket can be a real score. But many times, when you have to pay to get something for free, that is a red flag that a scammer is at work. You should never send money, even for postage, to a company that you don?t know. Also, keep an eye on the costs for things like postage even if you do know the company name. If they?re asking for $50 postage to send you a free magazine, then you know something is up. Lastly, beware giving out too much personal information. There?s no reason a company giving away free shampoo needs your bank account details. Protect your private info and if you?re unsure, move on to the next freebie offer.