HVAC Control in the New Millennium.pdf - HVAC.Amickracing

HVAC Control in the New Millenniumresponsibility to ensure that the communication was completed.By the late 1970s, there was a need to standardize the way computerson the Internet communicated with each other. This resulted in TCP/IP. TCP/IP stands for Transmission Control Protocol and Internet Protocol.These networking protocols allow different types of computers tocommunicate.In the mid-1980s, the government became concerned about thesecurity of defense information and split the network into ARPAnet andMilNet. The responsibility of ARPAnet was moved over to the NationalScience Foundation (NSF), which merged ARPAnet into the high-speednetwork called NSFnet.NFSnet became the prototype for national backbones. The highspeedlinks were T1 phone lines which served as the main traffic arteriesacross the country. Network traffic increased until the computers controllingthe network and the telephone lines connecting them were overloaded.In 1987 the old network was replaced with faster telephone linesand faster computers to control it.The system began to be used for a wider variety of data and thenational Internet emerged. In 1992 the NSFnet backbone was upgradedto higher-speed T3 links, which operated at a speed of 45 Mbps.In 1995 NSF released control of the Internet backbone to the commercialcarriers. Since then, NSF has focused on providing regional Internetconnections and building a faster backbone. The Internet grewand became a practical method of communication for different computersfrom various sites and companies.The Internet is the largest network we have, with all types of differentcomputers connected to it. These computers talk to each otherusing protocols, which set the rules of communication. Without a commonset of rules the different computers would not be able to send andreceive information among themselves.The protocols that make up the Internet are the Transmission ControlProtocol (TCP) and Internet Protocol (IP). TCP breaks down informationinto packets or envelopes of data for transfer and reassemblesthem at the destination point. IP ensures the proper delivery of data tothe right address.Any computer that wants to communicate with any other computeron the Internet must use TCP/IP. Associated with the TCP/IPprotocol are several TCP/IP applications or tools for sending and receivingelectronic mail, transferring files, and accessing files remotely.©2001 by The Fairmont Press, Inc. All rights reserved.