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The Internet and the World Wide Web Basics The internet was originally created as a means of redundant communication links between many places without disruption of service should one site have been taken out by nuclear attack. All sites are connected to all other sites and talk to specific systems through protocols. The fundamental reason the World Wide Web was created was to provide a way to view information other than just text. However, when the web was initially created the speed and volume of communication was very limited. The limited bandwidth spawned the idea of a mark up language that instead of sending large amounts of formatted data, the description of the data would be sent in a standard ASCII file and a secondary program would produce the final presentation and link the documents to other relevant material. This was the birth of hypertext markup language (HTML). This section will show the basic working principles of the web to effectively maintain your website. This knowledge is absolutely necessary to understand and will help to speed the update and resolution of problems. The Global Network The Internet is a global network of computers linked together through a communications infrastructure. It is far bigger than just the World Wide Web even though the web is the highest usage to the average person. The important thing to remember in working on the internet is the origins. All current technology is based on the fundamentals of this original network of linked military and academic institutions. The infrastructure, standards and conventions, and protocols make the system work in a modular fashion. There is no great supercomputer or core database that controls the internet. The main controlling factors are the limited governing bodies that administrate the network itself. Physical Infrastructure and Protocols The internet at the basic level is no more sophisticated than a small office network. The internet was created and lives dynamically in the UNIX environment. The original net ARPNET were mainframe UNIX computers linked together over ordinary phone lines. As an early internet user a person would connect as if it were a UNIX terminal. In making this connection a person would then be connected to all of the mainframes on the net. The infrastructure today has so much traffic that higher bandwidth connections are in place. These are called the internet backbones. There a several to maintain the redundant capabilities of the network. Because one system will have multiple connections to others a physical “Web” of connections is made. The World Wide Web is a description of this network phenomenon and is the most common use. Figure (1) shows how the connections are made and Figure (2) shows how they are typically referred to. Toronto Ottawa Vancouver Home #2 Home #1 New York Los Angeles Figure 1 - Basic Connectivity Toronto Ottawa Vancouver Home # 1 Los Angeles New York Figure 2 - Network Diagram of the Internet What allows all of this to work is the use of the Transmission Control Protocol/Internet Protocol (TCP/IP) protocol. Each system on the network must have a unique internet address. Every web server, every home or office user and every device that is connected to the network has its own address. When two systems are communicating what they will do is to send the information everywhere at the same time. If you look at figure 1 you can see a multitude of paths from Home #1 to Home #2. The complexity of all the connection reduces to the cloud shown in figure 2. The combination of address and the TCP/IP protocol to almost guaranteed transmission success. Most problems therefore occur in the main single connections from the home to the Internet service provider. The website would be located in the equivalent of Toronto on the Bell Nexxia servers as you can see they are well connected. If you think of all the people on the internet sending and receiving information at the same time to everywhere it would get extremely congested. In Home #2 fact some viruses attempt to do this. The combination of technologies such as bridges and routers act as the traffic control systems by directing the information in the direction it needs to go and blocking from where it doesn’t need to go. More information on this is available but is not necessary for the purposes of this course. The other major controlling technology on the web is databases. You might be surprised at how many you use without even knowing. All are located on the servers that make up the internet. Web Servers The web server is the main host for the website. Hosting simply means your files are honored guests on the web server connected to the internet. The website is located at an Internet Protocol address like 198.13.78.256. That is hard to remember let alone having someone else try to remember. If you were to put in the number it would work however www.yourwebsite.com uses the combination of Universal Resource Locator (URL) and Domain Name Service (DNS). They run on the power of UNIX databases. Universal Resource Locators and Domain Name Service Servers www.website.com is a URL. When a user types this into a browser and clicks go, the URL is sent to the nearest DNS server where the database is queried for the IP address. Because of the nature of the internet itself there are literally thousands of DNS server databases around the world to allow the use of URLs. This system works because each user has a unique IP address. The IP address is looked up in what is called the WHOIS database which you might be familiar with from office networking. When the site is registered as an internet domain all of the servers around the world must synchronize the information. This process usually takes approximately twenty four hours. The number of DNS servers explains why people in Paraguay may be able to access the site while people in Portugal cannot since it has not reached their DNS servers. One of the advantages of this technology is that you can find out who is looking at your site. Most hosting services log the IP address of the users that request information from the Site. The WHOIS databases provide information for demographic reporting on the visitors to the site. For example a former Radio Tracking company’s website produced reports from Australia Post, New Holland Tractors and the US Military as well as others. It provided the sales team with the information of who is interested in the product or service. This could be valuable in targeting new groups of prospects for the company simply by printing the report. There are also many security features to this but that is beyond the scope of this manual. Search Engines Search engines are simply online databases. They store all of the key information for a site. The user simply queries the database for like criteria. The database then displays the information matching the criteria in alpha numerical order. This being known, a few people realize that if they start there entry with a 1 or A such as #1 Investment Counseling they have the greatest chance at being at the top of the list displayed. Yahoo and Google are currently the most widely used and work on this principle. Some other engines such as Lycos and WebCrawler use what are called robots or AI (artificial intelligence). It sounds complicated but what they are doing is actively searching the WHOIS databases on the DNS Server and recording into a database what is found on the site. The program isolates key words from Meta data on web pages and this is the information that the queries are done on. The program is far from perfect and most people prefer the results from the manually entered databases.