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Web Hosting - The Internet and How It Works In one sense, detailing the statement in the title would require at least a book. In another sense, it can't be fully explained at all, since there's no central authority that designs or implements the highly distributed entity called The Internet. But the basics can certainly be outlined, simply and briefly. And it's in the interest of any novice web site owner to have some idea of how their tree fits into that gigantic forest, full of complex paths, that is called the Internet. The analogy to a forest is not far off. Every computer is a single plant, sometimes a little bush sometimes a mighty tree. A percentage, to be sure, are weeds we could do without. In networking terminology, the individual plants are called 'nodes' and each one has a domain name and IP address. Connecting those nodes are paths. The Internet, taken in total, is just the collection of all those plants and the pieces that allow for their interconnections - all the nodes and the paths between them. Servers and clients (desktop computers, laptops, PDAs, cell phones and more) make up the most visible parts of the Internet. They store information and programs that make the data accessible. But behind the scenes there are vitally important components - both hardware and software - that make the entire mesh possible and useful. Though there's no single central authority, database, or computer that creates the World Wide Web, it's nonetheless true that not all computers are equal. There is a hierarchy. That hierarchy starts with a tree with many branches: the domain system. Designators like .com, .net, .org, and so forth are familiar to everyone now. Those basic names are stored inside a relatively small number of specialized systems maintained by a few non-profit organizations. They form something called the TLD, the Top Level Domains. From there, company networks and others form what are called the Second Level Domains, such as Microsoft.com. That's further sub-divided into www.Microsoft.com which is, technically, a sub-domain but is sometimes mis-named 'a host' or a domain. A host is the name for one specific computer. That host name may or may not be, for example, 'www' and usually isn't. The domain is the name without the 'www' in front. Finally, at the bottom of the pyramid, are the individual hosts (usually servers) that provide actual information and the means to share it. Those hosts (along with other hardware and software that enable communication, such as routers) form a network. The set of all those networks taken together is the physical aspect of the Internet. There are less obvious aspects, too, that are essential. When you click on a URL (Uniform Resource Locator, such as http://www.microsoft.com) on a web page, your browser sends a request through the Internet to connect and get data. That request, and the data that is returned from the request, is divided up into packets (chunks of data wrapped in routing and control information). That's one of the reasons you will often see your web page getting painted on the screen one section at a time. When the packets take too long to get where they're supposed to go, that's a 'timeout'. Suppose you request a set of names that are stored in a database. Those names, let's suppose get stored in order. But the packets they get shoved into for delivery can arrive at your computer in any order. They're then reassembled and displayed. All those packets can be directed to the proper place because they're associated with a specified IP address, a numeric identifier that designates a host (a computer that 'hosts' data). But those numbers are hard to remember and work with, so names are layered on top, the so-called domain names we started out discussing. Imagine the postal system (the Internet). Each home (domain name) has an address (IP address). Those who live in them (programs) send and receive letters (packets). The letters contain news (database data, email messages, images) that's of interest to the residents. The Internet is very much the same.

Got Java on the Brain? Get Free Coffee Products! There are many wonderful web pages on the Internet that help their users and visitors to free products. Some of the pages hold links to free samples; others offer coupons and advice on how to get free products. If it is Java that is on ones mind and one is looking for free coffee products, there might just the right web page on the Internet for that. Finding pages that offer free java, is as easy as drinking a cup of coffee. Internet savvy persons just need to enter the words free coffee into any of the Internet search engines and a variety of great pages will pop up on the search screen. Coffee pages offer samples, links to samples, coupons and more on their sites. Any coffee lover has the chance to try a great variety of new and fancy coffees. The Internet pages that offer free coffee samples are updated frequently, so that links should not be outdated and new products are listed as soon as they appear on the market. As with so many pages on the Internet, these web sites rely on their users to help out with new sample tips, coupon tips and promotion dates. Users are asked to contact the web page master whenever there is a link that is not working, so that that link can be fixed or removed. Users are also encouraged to send in any data about free samples, links to company pages that offer free coffee and even links to coupons and deals that are unbeatable. Since free coffee is sometimes hard to get too and there are only that many free samples that coffee lovers can get a hold of, many of the free coffee sites also offer other great free deals and links to coupons and samples, so that it is anyways a good idea to visit the free coffee sites. For coffee lovers it is also important to check out their local coffee stores. Many of the stores have promotions, such as an advertisement campaign, where free coffee in connection with other products might be available. Just recently one of the major coffee chains had an ongoing promotion, where coffee lovers bought their friends a coup of coffee and they themselves received their drink of equal or lesser value for free. This might have been a way of the company to lure m ore new customers, but in the end it meant a free coffee for one of the two friends. Sometimes it is a promotion at one of the local festivals, where coupons and vouchers for free coffees are handed out. How about a free coffee with breakfast? Some of the major breakfast places offer a free complimentary coffee, when a breakfast or a breakfast sandwich is bought. For the person that every once in a while or maybe even every morning gets a breakfast sandwich, a bagel or a doughnut at one of the many restaurants this is a good deal. By the way, if coffee is not the desired morning drink, but rather teas, the websites and coffee shops also offer free tea and free tea samples. Even though it is more rare, the pages also offer samples for hot chocolate and new chocolate drink creations that can replace coffee or tea for the ones who rather like it sweet and chocolaty with their breakfast. Whichever one if desired, it is well worth checking out the Internet pages online that offer free samples. Free samples are the way for the customer to try without buying. After all, no one would buy a car before it was not test-driven, so here is the chance to test-drink coffees and more.

Web Hosting - Redundancy and Failover Among the more useful innovations in computing, actually invented decades ago, are the twin ideas of redundancy and failover. These fancy words name very common sense concepts. When one computer (or part) fails, switch to another. Doing that seamlessly and quickly versus slowly with disruption defines one difference between good hosting and bad. Network redundancy is the most widely used example. The Internet is just that, an inter-connected set of networks. Between and within networks are paths that make possible page requests, file transfers and data movement from one spot (called a 'node') to the next. If you have two or more paths between a user's computer and the server, one becoming unavailable is not much of a problem. Closing one street is not so bad, if you can drive down another just as easily. Of course, there's the catch: 'just as easily'. When one path fails, the total load (the amount of data requested and by how many within what time frame) doesn't change. Now the same number of 'cars' are using fewer 'roads'. That can lead to traffic jams. A very different, but related, phenomenon occurs when there suddenly become more 'cars', as happens in a massively widespread virus attack, for example. Then, a large number of useless and destructive programs are running around flooding the network. Making the situation worse, at a certain point, parts of the networks may shut down to prevent further spread, producing more 'cars' on now-fewer 'roads'. A related form of redundancy and failover can be carried out with servers, which are in essence the 'end-nodes' of a network path. Servers can fail because of a hard drive failure, motherboard overheating, memory malfunction, operating system bug, web server software overload or any of a hundred other causes. Whatever the cause, when two or more servers are configured so that another can take up the slack from one that's failed, that is redundancy. That is more difficult to achieve than network redundancy, but it is still very common. Not as common as it should be, since many times a failed server is just re-booted or replaced or repaired with another piece of hardware. But, more sophisticated web hosting companies will have such redundancy in place. And that's one lesson for anyone considering which web hosting company may offer superior service over another (similarly priced) company. Look at which company can offer competent assistance when things fail, as they always do sooner or later. One company may have a habit of simply re-booting. Others may have redundant disk arrays. Hardware containing multiple disk drives to which the server has access allows for one or more drives to fail without bringing the system down. The failed drive is replaced and no one but the administrator is even aware there was a problem. Still other companies may have still more sophisticated systems in place. Failover servers that take up the load of a crashed computer, without the end-user seeing anything are possible. In fact, in better installations, they're the norm. When they're in place, the user has at most only to refresh his or her browser and, bingo, everything is fine. The more a web site owner knows about redundancy and failover, the better he or she can understand why things go wrong, and what options are available when they do. That knowledge can lead to better choices for a better web site experience.