are limited by the speed at which they can make this translation. Later in the chapter, modem speeds and types will be discussed at greater length. Computers can speak with each other in various methods over telephone lines. Circuit switching is when one computer directly dials up another. As phone lines in and out of locations began to become"busy"at times, the multiplexing idea was born. This allows an electronic cue system where computers may line up to access the next available line when one computer is done. Various forms of multiplexing have been developed to hold the data to be transmitted until an outgoing line is available, then delivering it. This eliminates the leed for the entire computer waiting for a path. Other tasks can be undertaken while the outgoing data is in eo This same early system is still the main access to the Internet for businesses and personal use. It allows anyone ess to the Internet anywhere in the world that telephone service is available. This now includes cellular applications and even direct satellite transmission for extremely remote locations. The system works very well and is expanding on a local access basis. As the Cold War continued, the government began the search for a system that would be less vulnerable to damage or sabotage. The U.S. Advanced Research Projects Agency(ARPA) began to explore an alternate path for government, business, and research locations to interconnect. This national network would allow different operating systems the ability to talk to each other and to route this path in a multitude of connects. Thus, if one path was damaged, the system would seek another path to its destination. The packet system of transmitting, which divides the information into streams of small packets of information, each with an I D number for final assembly, was developed. This new network would allow scientists from around the country to connect to one another to further computer technology. The system would be able to share equipment, transfer data files, and use long distance login capabilities. However, according to one of its early developers, Vint Cerf, vice-president of the Corporation for National Research Initiatives, ..we didn,'t know that e-mail was important.we weren't even sure what it was at the time"Dern, 1994. This new network would be called ARPAnet Soon researchers at private companies and institutions of higher learning were cranking out new software protocols to allow computers access to this new highway. In 1969, the first three aRPanet participants were linked between Stanford University in Palo Alto, California, and the University of California at Los Angeles and the University of California at Santa Barbara. The system grew slowly for the first decade, a bit faster over the next 10 years, and exploded in the 1990s as protocols, access, and individual desk top computers increased o During these years many operating systems, high speed(including fiber optic)transmission lines,access oviders, and language protocols were developed. The Defense Advanced Research Projects Agency developee a protocol for network interconnection called Transmission Control Protocol/Internetworking Protocol (TCP/IP). In 1983 this protocol was adopted as the standard for what would later be called Internet. 99.3 The Internet Today Today the Internet is a conglomeration of a huge number of interconnected LANs around the world. These are a series of linked IPs, functioning on their own, but able to instantly connect with any other LAN likewise lected to the Internet. It also covers the thousands of personal computers at home or in the office. The Internet can also connect to a wide range of other networks, including privately operated ones like America On Line, Prodigy, and Compuserve, plus hundreds of other special networks now in use throughout the world of speed, capacity, and reliability begin to crop up. These will be discussed later in the dhaple. et problems All you need is their IP, email account, or Web site address. As more and more users access the Internet problems The operating system most used by computers on the Internet is Unix. This system was developed by AT&T Bell Labs. This system uses characters on a menu or command message to access files. For more detailed information on Unix see [ Dern, 1994] The Internet has four major services: (1)electronic mail(email),(2)telnet, (3)file transfer protocol(FTP), nd( 4)client/server connections. Discussion on each service follows 1. Email--Probably the most used process on the Internet, email is a text transfer of messages from one point to another. Email addresses will route a message anywhere in the world in seconds. Several email programs are in use, from free shared systems such as Elm, Pine, Mailx, and Eudora. Recently some e 2000 by CRC Press LLC© 2000 by CRC Press LLC are limited by the speed at which they can make this translation. Later in the chapter, modem speeds and types will be discussed at greater length. Computers can speak with each other in various methods over telephone lines. Circuit switching is when one computer directly dials up another. As phone lines in and out of locations began to become “busy” at times, the multiplexing idea was born. This allows an electronic cue system where computers may line up to access the next available line when one computer is done. Various forms of multiplexing have been developed to hold the data to be transmitted until an outgoing line is available, then delivering it. This eliminates the need for the entire computer waiting for a path. Other tasks can be undertaken while the outgoing data is in the hold position. This same early system is still the main access to the Internet for businesses and personal use. It allows anyone access to the Internet anywhere in the world that telephone service is available. This now includes cellular applications and even direct satellite transmission for extremely remote locations. The system works very well and is expanding on a local access basis. As the Cold War continued, the government began the search for a system that would be less vulnerable to damage or sabotage. The U.S. Advanced Research Projects Agency (ARPA) began to explore an alternate path for government, business, and research locations to interconnect. This national network would allow different operating systems the ability to talk to each other and to route this path in a multitude of connects. Thus, if one path was damaged, the system would seek another path to its destination. The packet system of transmitting, which divides the information into streams of small packets of information, each with an I.D. number for final assembly, was developed. This new network would allow scientists from around the country to connect to one another to further computer technology. The system would be able to share equipment, transfer data files, and use long distance login capabilities. However, according to one of its early developers, Vint Cerf, vice-president of the Corporation for National Research Initiatives, “...we didn’t know that e-mail was important...we weren’t even sure what it was at the time” [Dern, 1994]. This new network would be called ARPAnet. Soon researchers at private companies and institutions of higher learning were cranking out new software protocols to allow computers access to this new highway. In 1969, the first three ARPAnet participants were linked between Stanford University in Palo Alto, California, and the University of California at Los Angeles and the University of California at Santa Barbara. The system grew slowly for the first decade, a bit faster over the next 10 years, and exploded in the 1990s as protocols, access, and individual desk top computers increased. During these years many operating systems, high speed (including fiber optic) transmission lines, access providers, and language protocols were developed. The Defense Advanced Research Projects Agency developed a protocol for network interconnection called Transmission Control Protocol/Internetworking Protocol (TCP/IP). In 1983 this protocol was adopted as the standard for what would later be called Internet. 99.3 The Internet Today Today the Internet is a conglomeration of a huge number of interconnected LANs around the world. These are a series of linked IPs, functioning on their own, but able to instantly connect with any other LAN likewise connected to the Internet. It also covers the thousands of personal computers at home or in the office. The Internet can also connect to a wide range of other networks, including privately operated ones like America On Line, Prodigy, and Compuserve, plus hundreds of other special networks now in use throughout the world. All you need is their IP, email account, or Web site address.As more and more users access the Internet problems of speed, capacity, and reliability begin to crop up. These will be discussed later in the chapter. The operating system most used by computers on the Internet is Unix. This system was developed by AT&T Bell Labs. This system uses characters on a menu or command message to access files. For more detailed information on Unix see [Dern, 1994]. The Internet has four major services: (1) electronic mail (email), (2) telnet, (3) file transfer protocol (FTP), and (4) client/server connections. Discussion on each service follows. 1. Email—Probably the most used process on the Internet, email is a text transfer of messages from one point to another. Email addresses will route a message anywhere in the world in seconds. Several email programs are in use, from free shared systems such as Elm, Pine, Mailx, and Eudora. Recently some