The Internet And Data CentersFrom this page you should learn How the Internet evolved from the phone network Unique aspects of the Internet How Internet data centers rely on fiber The Internet Understanding the Internet is much easier if you already know about other types of networks like telecom and data networks – the networks which the Internet connects. The Internet began as a government data communications network operating over the digital telephone network and morphed into the Internet we know today. The Internet was designed to connect computers and computer networks to transmit data and be survivable. The network architecture was similar to the phone network, what we call a mesh network where any connection point would be connected to several other connection points, like the diagram below.  A "mesh" network Connecting computers was different from connecting people making voice calls. Thus Internet protocols diverged from the phone system. The phone network was programmed to connect users along known connections and maintain the connection for the duration of the phone conversation. The Internet was designed to send large packets of data between computers and to allow connections to be determined as necessary, to find the addressee if it was not already known. The rules under which it operates, the Internet Protocol or IP, was designed to swiftly and reliably transfer large amounts of digital data. Rather than programmed switches, the Internet used a technique called routing. Transferring data on the Internet involves a computer connecting to a router. If a router sees an address it recognizes, it sends it to the router where it knows it will be forwarded. If that router is busy, it sends it to another router which then helps find an open path to the addressee. If a router does not recognize the address, it asks other routers around it if they know that address until it can find a route to the addressee. In the phone system, the switches needed to know how to send a signal from switch to switch while the Internet can learn on its own. In addition, the phone system relied on the network owner adding users to the programming while the Internet allowed new users to just join the network. Routers would learn about the new device and share its address with others.  The Internet connects all types of users There is another difference between a telephone network and the Internet. Generally, a phone network is owned by one company. Before the breakup of AT&T in 1984, they owned the cables and wireless links connecting switches, the switches, right down to the phone in the home or office. Post divestiture, the user could own their own phone, but the rest of the network was still owned by the phone company. The Internet is not owned by any one company or organization. The Internet routers are connected by fiber optic cables on land and under the seas which are owned by many different organizations. The Internet is essentially “open source.” Connections to the Internet can be from Internet service providers (ISPs) which can be independent ISPs, CATV companies, telephone companies or anyone else who leases a connection to the Internet from a Tier 1 Internet service provider and connects users on cabling or wireless. The Tier 1 Internet service providers include:
Tier 1 providers are also present in the United Kingdom, Australia, New Zealand, Sweden, Turkey, Finland, Germany, South Africa, India, Spain, France, Italy and Ghana and others servicing every country in the world. Corporations, colleges and universities, research organizations or other large organizations may have their own private connection from their LAN to the Internet and have their own data centers and users on their LAN. Organizations may build data centers, one of the fastest growing areas today, to store data and serve it to users. Government agencies of many types will have Internet connections for their various purposes. Virtually all direct connections to the Internet will be on fiber optics due to the high speed of the connection, probably a minimum of 1 gigabit/second and perhaps 10 or 100 gigabits/second for larger ISPs. When the Internet became widely available in the mid-1990s, the telecommunications backbone in most developed countries had been converted to fiber optics and submarine fiber optic cables were being built rapidly to connect the continents. In remote areas, wireless or satellite connections are still used for the Internet. What Is A Data Center? Data centers are facilities that store and distribute the data on the Internet. With an estimated 100 billion plus web pages on over 100 million websites and millions of videos available for streaming, data centers contain a lot of data. With about five billion users accessing all these websites, including a growing amount of high bandwidth video, it’s easy to understand but hard to comprehend how much data is being uploaded and downloaded every second on the Internet. (We won’t bother quoting statistics on Internet traffic, the numbers are too large to comprehend! And it keeps growing.) The main functions of a data center are to centralize and consolidate information technology (IT) resources, house network operations, facilitate e-business and to provide uninterrupted service to mission-critical data processing operations. More recently data centers have been dedicated to the massive computing needs of AI. A data center is what we used to call the computer room before it grew to fill giant buildings. Data centers can be part of an enterprise network, a commercial venture that offers to host services for others or a co-location facility where users can place their own equipment and connect to the service providers over the building’s connections. Data centers can be big like an Amazon, Facebook or Google “hyperscale” data center or small like what we used to call the computer room in enterprise LANs. Data centers are filled with tall racks of electronics surrounded by cable racks, power cables and cooling equipment. Data is typically stored on big, fast hard drives or solid state memory storage. Servers are computers that take requests and move the data using fast switches to access the data. Fast switches move the data. Routers connect the servers to the Internet. In the data center, speed is of the essence. Servers are very fast computers optimized for finding and moving data. Likewise, the storage, switches and routers are chosen for speed. Data center interconnections use the fastest methods possible. Faster speed means lower latency, the time it takes to find and send the data along to the requester. In larger data centers connections are at 100 gigabits/second or faster. While speed is a primary concern for data centers, so is reliability. Data centers must be available 24/7 since all those 2 billion Internet users are spread all around the world. Reliability comes from designing devices with redundancy, using mesh networks, backups for storage, uninterruptible power and reducing the nemesis of reliability, heat. Heat is generated by all the electronics, and the faster they run, the more power they consume and the more heat they produce. Data centers consume vast amounts of power. Getting rid of heat requires lots of air conditioning which can consume as much power as the data center electronics itself. Data centers have even been built underwater to facilitate cooling. Read about Data Centers here. Table of Contents: The FOA Reference Guide To Fiber Optics |
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