Frequently Asked Questions About the Internet Diagram

On the Internet, a router is a device that determines the next network point to which a packet should be forwarded toward its destination. A packet is the unit of data that is routed between an origin and a destination on the Internet.

Each of these packets is separately numbered and includes the Internet address of the destination. The individual packets for a given file may travel different routes through the Internet. When they have all arrived, they are reassembled into the original file.

The router is connected to at least two networks and decides which way to send each information packet based on its current understanding of the state of the networks it is connected to. A router is located at any juncture of networks or gateway.

A router creates or maintains a table of the available routes and their conditions and uses this information along with distance and cost algorithms to determine the best route for a given packet.

A "name server" simply takes a domain name, like www.name.com and assigns it an "Internet Protocol Address" Number such as 24.162.247.30 and keeps this on file.

This IP # is actually how the Routers are able to "find" a particular computer on the Web.

On the Internet, a virtual server is a server (computer and various server programs) at someone else's location that is shared by multiple Web site owners so that each owner can use and administer it as though they had complete control of the server.

Using a virtual server, a company or individual with a Web site can not only have their own domain name and IP address, but can administer their own file directories, add e-mail accounts and address assignments, assign multiple domain names that resolve to a basic domain name without involvement from the ISP, manage their own logs and statistics analysis, and maintain passwords.

On the Internet, the root server system is the way that an authoritative master list of all top-level domain names (such as com, net, org, and individual country codes) is maintained and made available.

The system consists of 13 file servers. The central or "A" server is operated by Network Solutions, Inc., the company that manages domain name registration, and the master list of top-level domain names is kept on the A server. (Top-Level domains are the .com, .net, .org, etc.

On a daily basis, this list is replicated to 12 other geographically dispersed file servers that are maintained by an assortment of agencies. The Internet routing system uses the nearest root server list to update routing tables.

Q. What is a server?
A. In general, a server is a computer program that provides services to other computer programs in the same or other computers. The computer that a server program runs in is also frequently referred to as a server (though it may contain a number of server and client programs). In the client/server programming model, a server is a program that awaits and fulfills requests from client programs in the same or other computers.

Specific to the Web, a Web server is the program (housed in a computer) that sends out requested HTML pages or files. A Web client is the requesting program associated with the user. The Web browser in your computer is a client that requests HTML files from Web servers.

Q. What is a Name Server?
A. Also called a host, a name server is a computer that has both the software and the data needed to locate domain names and display websites to browsers. In other words, it finds websites by taking a name like profitgate.net and locating the address numbers assigned to that domain name, then sending a browser the data contained on that website. This is a vital, basic function that allows the Internet to work.

Q. What about sub-domains? How do these fit in?
A. Looking at the above chart and information, you can see that the IP Address is the key to every web site's location on the Internet. Once a "web surfer" is connected to a Top Level Domain such as www.profitgate.net - then the owner of that domain may "sub-lease" files under that address.

Example: www.yourname.profitgate.net/

Now, you can create pages under this subdomain, such as . . .

Example: www.yourname.profitgate.net/mainpage.html

Think of the IP # as your street address number and the Name Server as your friendly local Post Office that hands out the numbers for new houses built, and thereafter sends the mail to that house. Say they give you an address of 201 Pine Street. You could then have sub-addresses, like 201-A, B, C and so on.

This is somewhat similar on the Internet. Any top level domain, like profitgate.net or microsoft.com can create sub-domains under it, or secondary domains.