ORTHO BYTES

The use of computers, computer programs, and other computerized equipment to assist in the orthodontic practice will be reported under this section of the AMERICAN JOURNAL OF ORTHODONTICS AND DENTOFACIAL ORTHOPEDICS. Manuscripts, comments, and reprint requests may be submitted to Dr. Martin N. Abelson, 14720 North Shotgun Pl., Tucson, AZ 85737.

An introduction to the Internet

Frederick J. Regennitter, DDS, a and John E. Volz, DDS, MPA b Fort Knox, Ky

Emergent and evolutionary technology is transforming the common office computer into a new tool as pioneering efforts in information tech- nology and personal productivity unfold. Many dental offices are already dependent on the work- horse applications of word processing for patient communications, spreadsheets for billing or sched- uling, and diagnostic imaging as forecasted in the late 1970s by Burstone. 1 In an early prophesing editorial, Watson also predicted the use of comput- ers in retrieving data from a future information industry. 2

Reminiscent of the hyperbole that accompanied the microcomputer when it debuted on the busi- ness and contemporary scene in the early 1980s, the "information highway" of the current administra- tion is making its way to households all over America in the form of a conglomerate of intercon- nected networks known collectively as the Internet. New users come to the Internet unsure of what the technology is and what it can do for them) They are both inquisitive about and intimidated by the vast information resources and power of the Inter- net. As powerful as the word processors and spreadsheets that replaced typewriters and calcula- tors, instant information access and transfer has many time saving advantages. Interestingly, Econoimides suggested that time shrinkage was what the computer was all about 15 years ago. 4

With most of the hardware already in his office, the clinician needs only a little insight and initiative

The views expressed in this article are exclusively those of the authors and do not reflect those of the Department of Army, the United States Army Dental Corps, the Department of Defense or other Departments of the United States Government. aColonel, U.S. Army Dental Corps; Former Director, Advanced Educa- tion in Orthodontics. bColonel, U.S. Army Dental Corps; Former Assistant Director, Advanced Education in Orthodontics. 8/1/60816

to participate in the world of telecommunications. The purpose of this report is to describe the Inter- net's historical background, additional hardware requirements, navigational aids, and potential uses of this advancing dimension in computer technol- ogy. Much of the background for this report has been gathered from an explosion of recently pub- lished books on the Internet. 5-11

HISTORICAL BACKGROUND OF THE INTERNET

The Internet has a magnet like effect attracting daily attention in the media. For an entity with secret and purposefully obscure beginnings the Internet is now a place to be. Defying a simple description, it is comparable to a fabric woven from thread formed by thousands of interconnected computer networks. Offices that have multiple computer terminals configured as a local area net- work (LAN) are comparable conceptually to the Internet, only smaller in scope. The Internet is an interoperable mesh of LANs, wide area networks (WANs), and geographic networks spanning the globe. Individual networks comprising the Internet are owned by research, governmental, commercial, and educational organizations plus a few persons. Although government has had a continuing role in its development, standardization, and providing ac- cess to the online world, there is no central author- ity regulating or controlling its use. Through an intriguing process the Internet has avoided becom- ing a Cold War relic and evolved into a silicon behemoth connecting more than 2 million host computers and facilitating data transfer measured in terabyte amounts.

Historically, the Internet goes back approxi- mately 25 years. Under the assumption that a nuclear war would disrupt command and control systems for the military, a reliable communications apparatus was needed. In 1964 Paul Baran, a re-

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searcher at the Rand Corporation, designed a novel doomsday communications system for the Department of Defense. His design took informa- tion flow and separated it into electronic fragments called packets. Each packet of information had a unique identifier as it was sent out by computers to their destination over the most direct route avail- able. It would be impossible to predict the surviv- ability of any one part of the nation's existing communications network during a disastrous event. Discrete packets might travel by telephone lines, radio waves, or fiber optic cables along with other packets going to different destinations. Because there were no critical transfer points, destroyed or busy links could be bypassed and the packets sent along alternative routes by packet switching nodes. The packet switching process became the basis for today's electronic transactions. The computer was the perfect tool for not only chopping up the information into the packets but also reassembling them. The project was developed by the Advanced Research Projects Agency (ARPA) and the result- ing computing network was known as ARPAnet. During the late 1960s and into the 1970s Baran's packet switching network gained prominence in select government and university research labora- tories because it facilitated the sharing of the few existing computers and it became a medium for intellectual exchange. 12-~4

In the mid 1980s the National Science Founda- tion (NSF) built the high-speed, long-distance data lines that form Internet's United States backbone. This backbone became known as the NSFnet, and it connected supercomputer centers with the notion that there would be more regional and midlevel networks interlaced with it. NSFnet would be the trunk line, or fast lane, for moving data between a limited number of nodes with smaller networks branching off. Two other major networks that formed in the 1980s included BITNET (Because Its Time Network) and CSNET (Computer Science Network). ARPAnet split off its military portion into a separate MILnet in 1983,The major costs for operating the growing Internet were shared in a cooperative arrangement with its primary users: universities, national laboratories, high-tech corpo- rations, and government agencies. 15

Despite its Cold War origins, the Internet is no longer the exclusive domain of the military and educators. Judging from the media glow that cur- rently surrounds it, the Internet seems to spark many imaginations but can it really provide the global shrinkage and accessibility to improved pro-

ductivity and knowledge sharing/acquisition that advocates claim? Does this colossal web of connec- tivity hold any use for the clinician? There have been high profile efforts at the local, state, and national levels to not only define and refine the Internet but to educate the general public in its availability and use.

Growing at the rate of about 10% per month, the Internet has become a global infrastructure for education, research, professional learning, public service, and business. This is no accident, and several administrations can be credited for support of the project. The High-Performance Computing Act, HPCC, of 1991, PL 102-194, was signed by President Bush on December 9, 1991, and helped fund the NSFNet. 16 This act focused on developing and applying high performance computers and soft- ware to eventually make information available over a faster network, the National Research and Edu- cation Network (NREN). The HPCC legislation establishing NREN directs resources not only for technologic improvement, but encourages K-12 educational access.

The Internet is also key building block for the National Information Infrastructure, (NII). The goal of the NII initiative is to create a vast network over telephone and cable lines connecting almost all citizens, corporations, and institutions in the same way telephones do today to encourage inter- change and distribution of information. 17 Making this work obviously requires the cooperation of government and business. Public funding for the NII is just getting started with $26 million in proposals submitted to the National Telecommuni- cations and Information Administration, NTIA, and the Department of Commerce by May 1995. In the private sector capital investment and media mergers have been directed toward acquiring dis- tributed systems. These are programs that could become the commercial conduits for the informa- tion highway because they run on many networked computers, la

Vice President A1 Gore is one of the leading proponents in NII's ongoing development. Nil ini- tiatives and consequently whatever lifeform the Internet eventually takes will be the result of com- mercial and governmental synergy. As described by the Clinton Administration, the information high- way will probably consist not only of computer networks but a variety of transmission technologies, including satellite, terrestrial microwave, interac- tive cable television, and telephone services. 19 The information itself may be in the form of video

216 Ortho bytes American Journal of Orthodontics and Dentofaciai Orthopedics February 1995

Table I. Some telecommunication terms

ANSI

Client

Dial-in (also dial-up)

Electronic Bulletin Board System (BBS)

Gateway

Host

Hypertext

InterNIC

Kbs (Kilo-Bits per Second)

LAN (Local Area Network)

Modem (MODulator/DEMod- ulator)

Network Access Provider (Network Service Provider)

PPP (Point to Point Protocol)

Server

SLIP (Serial Line Internet Protocol)

Terabyte

TCP/IP (Transmission Control Protocol/Internet Protocol)

UUCP (Unix-to-Unix CoPy)

UNIX

VTIO0

The American National Standards Institute is responsible for implementing guidelines for in- dustry including data transfer.

A program or computer that requests information from a remote computer server.

A connection, usually made through modems, between two computers (or servers) over stan- dard voice grade telephone lines.

A computer, and associated software, which typically provides electronic messaging services, ar- chives of files, and any other services or activities of interest to the bulletin board system's operator. Many BBSs are currently operated by government, educational, and research insti- tutions in addition to hobbyists.

A computer present on two networks that can exchange information on both systems.

A computer system that is a connection source for network information services.

A user defined associative path facilitating a textual information search used in search devices like WWW, World Wide Web.

A Network Information Center (NIC), funded by the National Science foundation, that pro- vides information about the Internet. The InterNIC is a team of three contractors, each of which focuses on a particular network support task. The three tasks are: Information Ser- vices, Registration Services, and Directory and Database Services.

A data transmission rate expressed in 1000 bit per second units. For example, 56 Kbs is 56"1000 = 56,000 bits per second.

A data network intended to serve an area of only a few square miles or less. Since such net- works are relatively small they can usually be directly controlled by the users and operate at relatively high speeds (up to 100 Mb/s [10 million bits per second] over inexpensive wiring.

A device that converts the digital signals used by computers into analog signals needed by voice telephone systems. Modems can be "dial" or "leased line" type. Dial type modems are used on normal telephone lines to call remote computers, and usually operate at speeds between 120 to 1,920 characters per second.

Any organization that provides network connectivity or dial-up access. Service providers may be corporations, government agencies, universities, or other organizations.

A protocol used to establish TCP/IP connections using serial lines such as dial-up telephone lines. Similar to SLIP (see below), PPP is a later standard that includes features such as de- mand dial-up, compression, better flow control, etc.

A network machine that provides retrievable files or access to databases.

A protocol used to establish TCP/IP connections using serial lines such as dial-up telephone lines. Small computers, such as PCs and Macintoshes, can use SLIP to dial up to servers, which then allow the computer to act as a full Internet node. SLIP is generally used at sites with a few users as a cheaper alternative than a full Internet connection. SLIP is being re- placed by PPP on many hosts.

1000 gigabytes

TCP/IP is named for two of the major communications protocols used within the Internet (TCP and IP). These protocols (along with several others) provide the basic foundation for com- munications between hosts in the Internet. All of the service protocols, such as FTP, Telnet, Gopher, use TCP/IP to transfer information.

This was initially a program run under the UNIX operating system that allowed one UNIX system to send files to another UNIX system via dial-up phone lines, today, the term is more commonly used to describe the large international network which uses the UUCP protocol to pass nuews and electronic mail.

A computer operating system popular on Internet hosts initially developed at AT&T Bell Labs.

A standard supported by many Internet hosts and emulated by other terminals and personal computers.

p rogramming, scientif ic or business databases, im- ages, sound recordings, l ibrary archives, and o ther media . Th is nat iona l agenda wil l surely in f luence future o r thodont ic pract ices.

COMMUNICATING ON THE INTERNET

With as many 10,000 in terconnected computer networks, 5 mi l l ion computers , and 20 mi l l ion users a round the wor ld, how does the In ternet keep f rom

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becoming gridlocked with information? An impor- tant feature that allows computers to talk with each other was the early implementation of a stan- dard protocol for transferring information and error checking known as Transmission Control Protocol/Internet Protocol (TCP/IP). This distinc- tion allows different types of computers to com- municate with each other to handle basic com- puter functions. Cray supercomputers, mainframes, UNIX workstations (Bell Laboratories, Murray Hill, N.J.) Macintoshs (Apple Computer, Inc., Cu- pertino, Calif.), IBMs (IBM Corp., Armonk, N.Y.), and IBM work alikes can all communicate with each other. Interoperability is the term used to describe this key feature that allows disparate com- puter systems, using a common network protocol such as TCP/IR to be interconnected successfully. 2

The Internet universe is a challenging experi- ence for the new user. There are parts of the information highway without shoulders and a few areas that are not yet paved. Many of the network's host computers run on a computer language known as UNIX. UNIX serves as an equalizer among different computer platforms, particularly the mainframes. While providing a common vernacular, it has an unfamiliar command language for neo- phytes trying to negotiate the web of some Internet services. There is a new set of technical nomencla- ture and acronyms (Table I). In addition, there are established customs and behavior for users, known as netiquette, which are important for this interac- tive medium.

Every computer on the Internet has a unique numerical identifier known as an IP (Internet Pro- tocol) address. This address is used to facilitate moving data physically between computers on the network. The Internet address is represented by four groups of numbers joined by dots. An exam- ple would be 140.147.2.69, which is the IP address for the Library of Congress. Numbers are great for computers but hard for people to remember so all Internet hosts also have a text name like marvel.loc.gov for the IP address given above. It can also be understood as a computer name, a location, and a domain name or analogously a street address, city, state, and nation. The last word after the dot is usually the organization or agency to which the host computer belongs. There are only a handful of these top level sites or domains. They include .edu, education, .rail, military, .net, network, .corn, commercial, .org, organization (usually nonprofit), and .gov, government.

Every person using the Internet needs an ac- count and a user ID. Every computer on the Internet, needs an IP address; fregenni@fiknox- arnedd.army.rnil, is an example of a person located at an Army medical facility on a military network. Locating computers with information and people on the Internet can be like doing detective work. Agencies and institutions can be found but specific persons or information sources are not listed in a telephone like directory. Krol's book is an excellent aid in locating information on the Internet. =

(To be continued in the March issue.)