2/19/2024 0 Comments Isp backboneMobile internet access can have profound implications for people in isolated areas. The story is similar in Ghana, Uzbekistan, Indonesia, South Africa, and Nigeria. For examle, 2.7 percent of Egyptians have fixed broadband service at home, but 10 times as many Egyptians have internet access using a cell phone. This is cost-effective because a single cell phone tower can provide service to hundreds of customers. But some developing countries are skipping the construction of fixed broadband networks altogether. In the developed world, people usually got fixed internet access first and obtained mobile internet devices later. This map shows the percentage of consumers around the world who have mobile internet access (note that the colors on this map are not directly comparable to the previous map). How the world gets online: mobile broadband penetration in 2012 And although the NSFNET was officially restricted to non-commercial use, for-profit companies were increasingly connecting to the network as well, setting the stage for the commercialization of the internet that followed. That meant that students and faculty at a growing number of universities had access to email, Usenet, and even a recently-invented application called the World Wide Web. By this time, there were 6,000 networks connected to NSFNET, with a third of them located overseas. This shows the NSFNET as it existed in 1992. Schools that didn't have a direct connection to the NSFNET worked together to build regional networks that linked them to each other and to the nearest NSF node. As a result, the NSFNET became the internet's "backbone," the high-speed, long-distance network that allowed different parts of the internet to communicate. But NSF decided not to limit NSFNET to that purpose, allowing the network to be used for a wide variety of academic purposes. The primary goal was to allow computer science researchers to log into the supercomputers and perform academic research. And in 1986 the agency created a TCP/IP-based network called NSFNET to link those supercomputing centers together and allow researchers across the country to use them. These networks still communicate with each other using the TCP/IP standards Cerf and Kahn developed in the 1970s.ĭuring the 1980s, the National Science Network funded several supercomputing centers around the United States. Today, the internet is made up of more than 40,000 different networks. By the time the ARPANET was decommissioned in 1990, it was just one of many networks that comprised the internet. ![]() This map shows the location of ARPANET and CSNET nodes (labeled "Phonenet"), which after 1983 communicated with each other using TCP/IP. One of the first new networks to connect to the new internet was CSNET, which was funded by the National Science Foundation to link computer science departments across the country. But the new standard paved the way for much faster network growth by lowering the barrier to entry for new networks. ![]() The switch to TCP/IP didn't make much difference from a user perspective - applications like email and Telnet worked about the same as they had before. On January 1, 1983, the ARPANET switched to using TCP/IP, marking the birth of the modern internet. These standards specified the basic format of data packets transmitted across the internet. The result was a set of standards known as TCP/IP. They decided that the network should be reorganized as a decentralized "network of networks." Under this scheme, different networks would be controlled by different organizations, but all the networks able to communicate using shared standards, forming a shared "internet." The military asked the computer scientists Robert Kahn and Vint Cerf to develop new networking standards to make this possible. But network operators realized that a centralized network would eventually become unmanageable if it continued to grow. ![]() Originally, the entire ARPANET was managed by the military.
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