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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.
Continuing Education Key to Being a Better Employee Employers now recognize the importance of continuing education for employees. Over the past few years, more and more employers have begun to offer tuition reimbursement and continuing education classes to their employees. While this was once thought of as an excessive expensive, it is now understood that continuing education benefits the company as much or more as it does the employee. The job market is becoming more and more competitive everyday. Only the best employees are getting jobs in certain sectors. That means that your skills need to be sharp in order for you to remain valuable to your company. This is where continuing education comes into play. No matter what type of job you have, just about all companies are investing in continuing education. The reasons why are simple. Even though the company may spend a good deal of money on continuing education for their employees, they see an even larger return. By having employees that are on the top of their game, the company will be more productive as a whole. Thus the company will make more money. With that in mind, it is very important that employees always take advantage of continuing education classes when they can. You will be able to stay on top of whatever new trends are coming up and possibly acquire skills that will allow you to move up in the company. By taking continuing education classes, you will become more productive. Studies have found that employees that continue to have their skills refreshed and renewed are more productive on the job. This is a perk for both employees and their employers. You will be able to finish more work in less time and with more understanding. Thus making your time at work easier. If you are not sold on the idea of continuing education, think of it this way. Your employer is paying for it. It is a perk of your job that you should take full advantage of. If you are working towards acquiring skills that will lead you to a promotion or an entirely new job, you are doing something to better yourself. And, it is costing you less, or nothing at all. The best companies to work for in the country have great training programs. This is no coincidence. These companies, which also make a ton of money spend thousands of dollars training their employees so that they can go out and make the company the most money possible. Less successful companies have begun to follow suit. No matter what type of job you have, there are continuing education programs that can help enhance your job experience. Continuing education is a great way to break out of a rut. If you are eager to change jobs or get a promotion, you will fair much better in the job market if you do some continuing education. Use whatever means your company offers to better yourself and become more marketable. The type of continuing education you choose depends on your career goals. It is always helpful to have an advanced degree in a certain field. If tuition reimbursement for graduate school is an option, take it. Having a Master’s or PHD will help you become an expert in your field of study. If your job has company continuing education, take them up on it., Even if a promotion is not exactly what you are looking for, being cross trained is always a good idea. Gain as much in the way of knowledge and skills as you can. When you move on to your next job those skills will look great on your resume. Web Hosting - Bandwidth and Server Load, What's That? Two key performance metrics will impact every web site owner sooner or later: bandwidth and server load. Bandwidth is the amount of network capacity available, and the term actually covers two different aspects. 'Bandwidth' can mean the measure of network capacity for web traffic back and forth at a given time. Or, it sometimes is used to mean the amount that is allowed for some interval, such as one month. Both are important. As files are transferred, emails sent and received, and web pages accessed, network bandwidth is being used. If you want to send water through a pipe, you have to have a pipe. Those pipes can vary in size and the amount of water going through them at any time can also vary. Total monthly bandwidth is a cap that hosting companies place on sites in order to share fairly a limited resource. Companies monitor sites in order to keep one site from accidentally or deliberately consuming all the network capacity. Similar considerations apply to instantaneous bandwidth, though companies usually have such large network 'pipes' that it's much less common for heavy use by one user to be a problem. Server load is a more generic concept. It often refers, in more technical discussions, solely to CPU utilization. The CPU (central processing unit) is the component in a computer that processes instructions from programs, ordering memory to be used a certain way, moving files from one place to the next and more. Every function you perform consumes some CPU and its role is so central (hence the name) that it has come to be used as a synonym for the computer itself. People point to their case and say 'That is the CPU'. But, the computer actually has memory, disk drive(s) and several other features required in order to do its job. Server load refers, in more general circumstances, to the amount of use of each of those other components in total. Disk drives can be busy fetching files which they do in pieces, which are then assembled in memory and presented on the monitor, all controlled by instructions managed by the CPU. Memory capacity is limited. It's often the case that not all programs can use as much as they need at the same time. Special operating system routines control who gets how much, when and for how long, sharing the total 'pool' among competing processes. So, how 'loaded' the server is at any given time or over time is a matter of how heavily used any one, or all, of these components are. Why should you care? Because every web site owner will want to understand why a server becomes slow or unresponsive, and be able to optimize their use of it. When you share a server with other sites, which is extremely common, the traffic other sites receive creates load on the server that can affect your site. There's a limited amount you can do to influence that situation. But if you're aware of it, you can request the company move you to a less heavily loaded server. Or, if the other site (which you generally have no visibility to) is misbehaving, it's possible to get them moved or banned. But when you have a dedicated server, you have much more control over load issues. You can optimize your own site's HTML pages and programs, tune a database and carry out other activities that maximize throughput. Your users will see that as quicker page accesses and a more enjoyable user experience. |