Full report

Original page 1

NASA Technical Memorandum 4567 Electronic Document Distribution: Design of the Anonymous FTP Langley Server Michael L. Nelson and Gretchen L. Gottlich Langley Research Center ° Hampton, Virginia National Aeronautics and Space Administration Langley Research Center • Hampton, Virginia 23681-0001 Technical Report March 1994

Original page 2

Original page 3

Nomenclature ASCII American Standard Code for Information Interchange DVI device independent FTP file transfer protocol HTML HyperText Markup Language ICASE Institute for Computer Applications LaRCNET Langley Research Center Network LTRS Langley Technical Report Server NAM NASA Access Mechanism NCSA National Center for Supercomputing NELS NASA Electronic Library System PC personal computer SGML Standard Generalized Markup Language SunOS SUN Operating System in Science and Engineering Applications TCP/IP Transmission Control Protocol/Internet Protocol WAIS Wide Area Information Server WATERS Wide Area Technical Report Server V_5_V World Wide Web p,'NF_IrJ_IG PA_E I11 BLANK NOT F'H.Ik/N[D ...

Original page 4

Original page 5

Abstract An experimental electronic dissemination project, the Langley Technical Report Server (LTRS), has been undertaken to determine the feasibility of delivering Langley technical reports directly to the desktops of researchers worldwide. During the first 6 months, over 4700 accesses occurred and over 2400 technical reports were distributed. This usage indicates the high level of interest that researchers have in performing literature searches and retrieving technical reports at their desktops. The initial system was developed with existing resources and technology. The reports are stored as files on an inexpensive UNIX workstation and are accessible over the Internet. This project will serve as a foundation for ongoing projects at other NASA centers that will allow for greater access to NASA technical reports. 1. Introduction The goal of the Langley Technical Report Server (LTRS) project is to implement a proof-of-concept technical report server accessible from desktops of researchers worldwide. Economics and expediency mandated the use of existing technology and resources. As a result, the technical report server went from conceptual design to production in 5 months. LTRS currently consists of a desktop UNIX workstation running an anonymous file transfer protocol (FTP) server (ref. 1), a widely used mechanism for transferring files over the Internet (refs. 2 and 3). The technical reports are distributed in PostScript format, a popular page description language from Adobe Systems, Inc. (ref. 4). Full-text searching on the reports is not available, but a Wide Area Information Server (WAIS) provides full-text searching of the report abstracts (ref. 5). The FTP and WAIS servers are available to anyone with Internet access. These servers can handle many simultaneous users without impacting the workstation's primary use. For example, with LTRS, the workstation's primary use in the development and evaluation of system software was not impacted. This project does not directly address user-interface issues, but work in this area by others should provide additional interface methods (refs. 6 to 9). This project was conceived in early September 1992. The FTP server first began production in mid-January 1993, and a WAIS server was added in February 1993. Existing tools, resources, and protocols were implemented to produce LTRS, which is currently used by hundreds of researchers worldwide. In addition, the FTP and WAIS servers will easily integrate into other NASA Internet access projects. This paper discusses the background objectives for LTRS, its design and implementation, its use during the first 6 months, its integration with other developing systems that build upon it, and opportunities for future work. 2. Background On-line libraries are the focus of many projects in library and information science (refs. 10 to 12). Libraries have vast amounts of information that is valuable only when easily accessed and utilized. A research laboratory's library provides services to experts in a variety of scientific disciplines. These researchers are the best in their fields and define tile leading edge of their respective technologies. Thus, to provide the best possible service, the information source that these researchers depend on should be as sophisticated as the systems that they use in their laboratory. 2.1. Meeting Customer Needs LTRS is an evolutionary step toward desktop document delivery. LTRS is tile combination of existing technology and the continual application of new methods that facilitate technology transfer and help an organization maintain its competitive edge. Many library customers at Langley request the ability to perform literature searches in their office and receive the resulting documents at their desk. Before LTRS, Langley library customers typically experienced a wait of 1 to 2 weeks for Langley formal technical reports. Library customers now have the option of acquiring these reports in a few minutes without leaving their office. 2.2. Objectives LTRS is not intended to replace traditional library services but rather to complement them. Users

Original page 6

whodo not wantto usethe systemor whodo not havethe resourcesto usethe systemcanstill access the currentsearchinganddocumentdeliverymethods. Thegoalof LTRSis to provideresearcherswith easy,familiar,andefficientaccessto Langleyformal technicalreports. Providingtechnicalreportselectronicallyisalsoanopportunityforthelibraryto expandintonewserviceareasandincreaseitsuserbase. LTRSallowsLangleyto easilyprovideinformationto nonlocalandevennonaerospaceresearchers. While anonymousFTP servershavebeenin use for severalyears(ref. 2), the informationin the Langley FTP server is its distinquishing feature. Many anonymous FTP servers exist, but the information is often of limited use or it simply duplicates information in other servers. The authors believe that LTRS is the first server to provide a significant number of technical reports concerning aerospace science and related disciplines. Anonymous FTP servers of technical reports have generally been maintained by computer science departments of universities or laboratories and have contained only computer science reports and information. The FTP and _,VAIS servers are widely accepted and robust mechanisms that require little maintenance. Past the initial start-up costs of creating the servers, distributing a report has no direct cost. The report servers can simultaneously support many users without performance degradation. Users receiving reports are responsible for printing hardcopies or displaying the reports on their terminals. Either way, the integrity of the report is maintained, the library incurs no direct cost in providing the report, and unreasonable search or retrieval demands are not placed on the customer. 3. System Design and Implementation The following sections details the design and implemcntation of LTRS. Design issues are discussed for the computer systems used for the servers, the format of tile reports, and the addition of WAIS searching. Finally, the current linfitations and their impact on these design issues are listed. vices have impacted the workstation's capability to perform other computing tasks. The largest impact 3.1. Document Server Implementation on the system is the disk space required to store the this class and Internet connectivity are all that is required to install an FTP server. (See ref. 14 for instructions for adding anonymous FTP capability to a UNIX workstation.) An FTP client on any architecture or operating system can access LTRS. (See appendix A.) UNIX was chosen for the implementation of the servers for several reasons. UNIX multiprocessing capabilities allow the machine to support any number of simultaneous FTP and WAIS sessions without severely impacting the local users of the machine. Both FTP and _VAIS are built around the clientserver model (ref. 15). A server is a separate entity that provides services to any number of clients who request them. A real-world example would have bankers and grocers as servers and community members as clients. Depending on the service needed, the banker or grocer is chosen and the transaction processed. Figure 1 shows the FTP client-server model where client access can take place over both local and wide-area networks. NASA Kennedy[ Figure 1. Sample session with LTRS simultaneously serving multiple clients. Very little computing power is required to support FTP and WAIS servers. Neither of these ser- Because a rapid prototype system was planned reports. Fortunately, high-capacity disk drives for and no additional resources were available, ex- workstations are readily available. For example, the isting resources were sufficient to create LTRS. current Sun IPX workstation, with 1.5 GB of storage, These resources included a Sun Microsystems IPX maintains 151 reports that consume almost 50 MB SPARCstation workstation running SunOS 4.1.2, (fig. 2) and still has sufficient space to support lo- Sun's implementation of UNIX (ref. 1). The work- cal users. This storage would not be possible if the station is connected to the Internet via LaRCNET, reports were not compressed. PostScript documents Langley's local network (ref. 13). A workstation of can become very large, especially when they contain

Original page 7

30 d 20 O I0 0 1991 1992 1993 Figure 2. Total storage for technical reports by year. 1991 1992 1993 Figure 3. Average size of a single report by year. graphics. Storage of uncompressed reports would quickly fill the system's disks. However, compression rates of roughly 70 percent are currently achieved and thus greatly reduces the storage requirement. Since the inception of LTRS, the average report size has increased (fig. 3) because more reports include PostScript figures. 3.2. Document Preparation LTRS would not have been possible without a quality product to distribute. For several years, the Technical Editing Branch (TEB) has been producing Langley's technical reports using TEX, a typesetting system for mathematically oriented manuscripts (refs. 16 and 17). TEB has been storing the TEX source files of the reports in anticipation of the authors needing to reuse them. These TEX source files were assembled into PostScript documents and made available to researchers via anonymous FTP. Using TEX to create electronically distributable reports can be summarized as a three-step procedure. First, source TEX files were processed into intermediate DVI (device independent) files, the only format TEX processors produce. A typical report could consist of as many as 10 to 15 separate TEX source files. Second, DVI files were converted to PostScript files. Third, the various PostScript files were concatenated in the correct order to produce a single file for each report. This procedure was used for the first 100 reports that were manually converted from TEX to PostScript. The output was checked with the corresponding hard copies to ensure that the integrity of the report was not compromised. After the initial reports had been reconstructed, TEB agreed to verify and supply all future reports in PostScript directly to the FTP server. Because a PostScript file is produced in the normal publication procedure, little work is required of TEB. To make the report available on the server, the abstract is extracted for WAIS and the report is placed in the appropriate file system for FTP access. Only PostScript versions of the reports were made available for the following reasons. Mainraining the integrity of the report is the top priority. The size and complexity of a PostScript version of these reports discourage casual alteration of the report. In addition, NASA could not distribute the reports in formats in which improper editing or printing of the file would compromise the quality and validity of the report. Because of the many locally developed TEX macros that are used to prepare the reports, the TEX source files were not suitable for distribution. Furthermore, distributing plain text (ASCII) versions is not feasible because the highly technical nature of the reports requires many equations and tables that cannot be represented in plain text. 3.3. What is Available Currently, 151 NASA Langley technical formal reports are available: Technical Papers (88 total), Technical Memorandums (58 total), Reference Publications (4 total), and Technical Translations (1 total). All reports are approved for "unclassified, unlimited" distribution and represent Langley's technical output in aerospace science and related fields. The reports currently span 3 years: 1991 reports (10 total), 1992 reports (109 total), and 1993 reports (36 total). Newly published reports are added as they become available. Figure 4 shows the file hierarchy in which the reports are stored. ASCII abstract lists are available by year, and for each report contain the title, author, report number, funding number, and abstract. 3.4. Wide Area Information Server (WAIN) Because PostScript files are not searchable with traditional text editing tools, the abstracts of the reports are available as ASCII files. Users can retrieve the abstract list and search it by using text editors or other standard utilities (e.g., the UNIX "grep" command). Although using a text editor to search a list of abstracts was acceptable for the prototype server, a more flexible and sophisticated searching method was

Original page 8

root bin dev etc pub usr techreports I larc 91 92 93 nasa-larc-abs.src I I I I I Technical reports and ] WAIS database definition abstract list for each year J Figure ,1. File hierarchy of technical reports on anonymous FTP server (techreports. larc. nasa. gov). Clearly needed. WAIS was chosen for searching the abstracts because WAIS is public domain software, is easy to use and maintain, and is increasingly popular (ref. 5). On February 10, 1993, a WAIS server was added to LTRS to allow keyword searching of abstracts. WAIS provides an easy-to-use interface that is accessible to both local and remote users. Building a WAIS database definition can be easily accomplished by using the indexing program included in the standard release of the WAIS software. Although only the ASCII abstracts were indexed for this project, WAIS can index many non-ASCII formats. 3.5. Current System Limitations To test these experimental services as quickly as possible, trade-offs were made. When the first author posted a USENET news article (ref. 3) to determine the level of interest in accessing technical reports via anonymous FTP, the response was overwhelmingly in favor of making the service available despite certain limitations. Users wanted access to the reports immediately, and they were willing to have tile service undergo refinements while in production. The initial limitations and constraints are discussed in the following sections. 3.5.1. How "automatic" is it? Full automatic desktop document, delivery is the goal. Although 4 LTRS makes significant strides toward this goal, it is not fully automatic. That is, the users are still responsible for the successful retrieval, decompression, and printing of the desired report. Figure 5 presents a sample FTP session. While a more automated system is desirable, LTRS is designed to provide only the basic system functionalib'. Because only widely accepted methods and protocols are used, the current services will serve as a core that other projects can build upon. fiddler%ftp techreports.larc.nasa.gov Name (techreports.larc.nasa.gov:mln) : anonymous Password: {type your e-mail address here} ftp> cd pub/techreports/larc/93 ftp> is -FC ftp> get README ftp> get abstracts.93 ftp> binary ftp> get tp3302.ps.Z ftp> exit fiddler% is fiddler% uncompress tp3302.ps.Z fiddlerZ ipr -Pmyprinter tp3302.ps fiddler% Figure 5. Sample FTP session transcript. 3.5.2. System implementation constraints. The current implementation of LTRS imposes some limitations. For instance, providing the technical reports in PostScript limits the usefulness of this service for those who do not have access to PostScript previewers or printers. While these resources are common in the scientific computing community, their use is not yet universal. Because PostScript files can become very large (e.g., several MB) especially if they contain figures, disk storage becomes an issue. For LTRS, the UNIX utility "compress" was used to reduce the storage required for the reports. The utility "uncompress" is needed by the user to restore the reports to PostScript format after they have been retrieved. Although UNIX systems have the uncompress utility, it may not be available on some non-UNiX systems. However, public domain versions of uncompression utilities exist for IBM PC and clones, Apple, Macintosh, and DEC VMS platforms. (See appendix B.) In addition to the storage benefit realized at Langley by compressing the reports, compression results in greatly reduced transfer times when retrieving reports. 3.5.3. Document completion. Perhaps the most limiting factor of the system is that not all reports are complete. The reports vary in the percentage of included figures. While all text, equations,

Original page 9

andnophoto- 4. LTRS Usage During First Six Months andtablesarepresent.,riot all figures graphsincludedin the hardcopyarepresentin the PostScriptversion.However,all figurelegendsare present,independentof the figureitself. Documentcompletenessis moreof anissuewith olderreports.Giventhe increasingpopularityof so- During the first 6 months of production, over 2400 technical reports were distritmted. Table 1 and figures 6 and 7 show the accesses during this period. No official or widespread advertising or support was utilized to increase awareness of this tools,recent service, and the numbers reported here do not reflect phisticatedgraphicsand visualization reportsoftenhavefiguresin PostScriptformat,which makesfor easyinclusioninto currentreports.Howpossible secondary distribution nor the distribution from other NASA sites that "mirror" (i.e., maintain ever, many older reports are incomplete. Scan- duplicate copies of) tile reports. ning the hardcopiesof olderreportsandproducing There have been 4730 FTP accesses to LTRS. The PostScriptoutput is a possiblesolution,but this largest, user group is domestic universities, accountmethodis labor intensiveand beyondthe scope ing for 37 percent of total usage (fig. 8). Domestic of this project. Scannedimagesand photographs companies accomlt for 11 percent of usage, which inare alsostorageintensiveand would requiresev- dicates significant progress in a new method of techeralordersof magnitudemorestoragethanwhat is currentlyavailable. 3.6. Security Issues Because the FTP server is available to anyone with Internet access, security concerns are paramount. The anonymous nature of tile service prevents validation of remote users. Two security concerns are the unrestricted access to government computers and the classification or limitations of the technical reports. As previously stated, only reports approved for "unclassified, unlimited" distribution are available. The authority for deciding which documents are eligible to be place(t on the server rests with the manager of the Technical Editing Branch. No restricted or sensitive documents are made available. Allowing anonymous access to a government computer is also a common concern. However, FTP access allows a user to retrieve only the files that are in the file system explicitly defined to hold anonymous FTP files. It is not possible to access files outside this file system during an FTP session. Ill addition, it is not possible for users to edit, remove, or place new files on the system. Making the reports available but requiring a password to acccss them is an option. However, the a(tministrative effort to validate the users, issue passwords, change the password frequently, and inform users of the correct p_sword is prohibitive. While this option would be effective in restricting access, there is still no way to control what happens with tile reports once they leave the server. Requiring a password would also inhibit other Internet applications such _ Gopher (ref. 18) and World Wide Web (W'_'%V) (ref. 7) from accessing the reports and thus slow the transfer of technology. nology transfer. Foreign usage, at 36 percent, has been significant, although most foreign accesses are from foreign universities. Table 1. LTItS Usage for 1/14/93 to 7/18/93 Separate FTP logins .............. 4730 Retrieval of abstract lists: 1993 list .................... 1069 1992 list ................... 1709 1991 list ................... 468 Total abstract lists ............... 3216 Retrieval of reports: Technical Papers (TP) ............. 1,'199 Technical MemoralMums (TM) .......... 895 Reference Publicatkms (RP) ........... 65 Technical Translations (TT) ........... 26 Total reports .................. 248,5 1500 1ooo ca E Z 500 TT RP TM TP Figure 6. Reports distrilmted by report type.

Original page 10

2O0O F 1500 1000 t- < 5O0 0 1993 1992 1991 Figure 7. Abstracts distributed by year. • Universities (37%) • Companies (1 1%) • NASA (9%) [] Government labs and DoD (3q_) [] Foreign (36%) [] Other (4c{) Figure 8. Access percentage by orgamzation. Tile 1993 abstracts and reports have not been available for the full 6 months. Given their limited numbers and late inclusion, users have expressed a greater interest in 1993 reports. Thus, the users of this service arc interested in obtaining the latest information and are less interested in older reports. Table 2 shows the titles of the top five most retrieved reports, exclusive of the report featured in the example session of the README file. While most of the reports had an even distribution of about 20 retrievals each, these 5 reports clearly stood out above the rest. For a complete listing of the companies, universities, research laboratories, and countries that have transferred reports and abstracts, see appendix C. Table 2. Top 5 Retrieved Reports 1. 72 Copies TITLE: Fault Tolerance of Artificial Neural Networks With Applications in Critical Systems AUTHOR(S): Peter W. Pretzel, Daniel L. Palumbo, and Michael K. Arras REPORT NUMBER: NASA TP-3187 2. 61 Copies TITLE: Grid Generation and Flow Solution Method for Euler Equations on Unstructured Grids AUTHOR(S): W. Kyle Anderson REPORT NUMBER: NASA TM-4295 3. 53 Copies TITLE: An Optimization-Based rntegrated Controls Structures Design Methodology for Flexible Space Structures AUTHOR(S): Peirnan G. Maghami, Suresh M. aoshi, and Ernest S. Armstrong REPORT NUMBER: NASA TP-3283 1. 52 Copies TITLE: Validation of Three-Dimensional Incompressible Spatial Direct Numerical Simulation Code AUTHOR(S): Ronald D. aoslin, Craig L. Streett, and Chau-Lyan Chang REPORT NUMBER: NASA TP-3205 5. 39 Copies TITLE: Gendraiized Hypercube Structures and H.vperswitct} Communication Network AUTHOR(S): Steven D. Young REPORT NUMBER: NASA TM-4380 5. Integration With Other Internet Systems As previously mentioned, the FTP and WAIS servers can be accessed from other Internet resource applications. Because LTRS is a proof-of-concept

Original page 11

sophis- centers, NASA contractors, and NASA research insystem, no time was budgeted to develop a ticated interface to the system. Following accepted stitutes such as Langley's Institute for Computer Apguidelines and protocols and not introducing Lang- plications in Science and Engineering (ICASE). ley specific features ensures that the FTP and WAIS servers flmction independently of the advances made 7. Concluding Remarks in new accessing mechanisms. Many other Internet access mechanisms are currently in use. Good introductions to WAIS, WW'W, Gopher, NCSA Mosaic, Archie, and others are included in references 2, 3, and 19 to 21. The Langley Technical Report Server (LTRS) confirms that researchers outside Langley, and cvcn outside the aerospace discipline can ca.sily search and retrieve NASA formal technical reports. The file transfer protocol (FTP) and Wide Area Information Many other Internet-based systems are under de- Server (WAIS) servers are not intended to supplant velopment that will provide library specific flmc- existing library systems but. are designed to provide tions. These systems include the NASA Electronic the library users with another vahmble tool. Users Library Systems (NELS) being developed at John- can now quickly perform their own searches and son Space Center (ref. 8), the NASA Access Mech- retrieve Langley formal teclmical reports from their anism (NAM) being developed at NASA Head- offices and thus free reference librarians to attend to quarters (ref. 9), and the Wide Area Technical Report Server (WATERS), a joint effort by the computer science departments of Old Dominion University, Virginia Polytechnic Institute and State University, University of Virginia, and the State University of New York, Buffalo (ref. 22). 6. Areas for Future Work While LTRS has been well received, many areas for improvement remain. The most obvious and immediate are the issues of document completion and more difficult reference questions. LTRS established a core service that was immediately useful. The generalized design of LTRS allows it to integrate with new technologies and systems such as World Wide Web ('_,W_rW), Gopher, and WAIS. Of the limitations that remain, document completion is perhaps the most pressing. Future reports can be expected to be more electronically accessible, but the addition of older reports (pre-1992) remains unresolved. the inclusion of older reports. In addition, the search, In the first 6 months, over 4700 users accessed retrieval, printing, and viewing capabilities of LTRS LTRS, and over 2400 technical reports were distribneed to be more flflly integrated and improved. Making the files available in formats other than PostScript would increase the potential audience for tile reports. Standard Generalized Markup Language (SGML) (ref. 23) and HyperText Markup Language (HTML) via Mosaic (ref. 6) are formats for consideration. LTRS should provide a foundation for developing multimedia technical reports. Tile long-range area of improvement is increasing the number of documents available; for example, LTRS could include reports from outside the current controlled, homogeneous publication environment. uted. This project has suecessfiflly shown that electronic report distribution is both feasible and desired by tile research community. Researchers have embraced the ability to have technical documents delivered to their desktop, even while advanced searching and retrieval interfaces for the server are under development. The benefit to the researcher is that document delivery is now measured in minutes, not day's, weeks, or even months. NASA Langley Research Center Hampton, VA 23681-0001 LTRS could also include reports from other NASA January 21, 1994 7

Original page 12

Appendix A Minimum System Configuration Needed To Access LTRS * IBM PC or clone,AppleMacintosh,UNIX workstation,or DECVMSwith Internetaccess • TCP/IP networkingsoftwarefor the above * FTP capability(providedwith mostTCP/IP implementations) • WAISclientsoftware(availablevia anonymousftp fromthink.corn) • PostScriptprinteror PostScriptpreviewingsoftware

Original page 13

Appendix B Anonymous FTP Location of Non-UNIX • VMS Compress/Uncompress Utilities unix.hensa.ac.uk:/pub/uunet/systcms/vms/compress_vms.tar • MS-DOS nic.cerf.net:/pub/infomagic_cd/dos/compress/comp430d.zip • Macintosh wuarchiv_, wust .d / mirr_rs / archiv.umich.du /ma / ut i/c_mpr_s_i_n /macc_mpress_.2.hqx 9

Original page 14

Appendix C Honeywell, Inc. Horizon Research Inc. Organizations That Have Accessed LTRS Hughes Aircraft Company Hughes Information Technology Company Companies Info Connections, Inc. Insignia Solutions Inc 3M Company Integrated Systems, Inc. ASK/Ingres Products Division AT&T Bell Laboratories Intel Corporation InterCon Systems Corporation Adobe Systems Inc. Allen-Bradley Company, Inc. Intergraph Corporation Intermetrics, Inc. Analog Devices, Inc. International Business Machines Anasazi, Inc. James Spottiswoode & Assoc. Apertus Technologies Inc Kendall Square Research Corporation Apple Computer Corporation BP LSI Logic Corporation Lockheed Software Technology Center BT North America, Inc. Beckman Instruments, Inc. Loral Corporation Biotcchnct Lucid, Inc. MEGATEK Corporation The Boeing Company Bolt Beranek and Newman Inc. Martin Marietta Corporation McDonnell Douglas Corporation Bristol-Myers Squibb Mentor Graphics Corporation Bull HN Information Systems Inc. Merck and Co., Inc. Byte Information Exchange CADAM Mobil Corporation CLAM Associates Monsanto Company Morgan Stanley and Company, Incorporated CST Entertainment Imaging Inc. Motorola Inc. CTA Incorporated Cellular Technical Services Netcom Online Communication Services Charles Stark Draper Laboratories Chevron Information Technology Co. Concurrent Computer Corporation Convex Computer Corporation Cray Research, Inc. Dallas Semiconductor Corp. Datapoint Corporation Dell Computer Corporation Delmarva Power and Light Company Digital Equipment Corporation Digital Express Group, Inc. Dupont Experimental Station EUTeC Eastman Kodak Epilogue Technology Corporation Exxon Research GTE Government Systems Corporation GTE Laboratories General Electric Company General Motors Research Laboratory Gordian Gulfstream Aerospace Corporation Halcyon Halliburton Company Harris Corporation Hewlett-Packard Hibbett, Karlson, and Sorensen Inc. 10 NEC Research Institute Corporation NorthWest Research Associates, Inc. Oracle Corporation PARAMAX SYSTEMS CORPORATION PDH Inc. Pacific Gas and Electric Company Panix Public Access Unix of New York Phillips Petroleum Company PictureTel Corporation The Pivot. Group Portal Communications Company Process Software Corporation Promis Systems Corporation QMS, Inc., Imagen Division Qualcomm inc. Rockwell International Corporation Rockwell Power Services Company SAIC SRI International Schlumberger Limited Sequent Computer Systems, Inc. Silicon Graphics, Inc. Software Tool and Die Solbourne Computer Inc. Southwestern Bell Corporation Sterling Software Stratus Computer, Inc.

Original page 15

SunMicrosystems,Inc. SunTechJournal SunquestInformationSystems TRW Inc. TelebitCorporation Texaco TexasInstruments ThinkingMachinesCorporation TransarcCorporation The TuringInstituteLimited UNIX SystemLaboratories UnitedTechnologiesCorporation VisualUnderstandingSystems Vitro Corporation The WollongongGroup XeroxPaloAlto ResearchCenter Universities AdelphiUniversity AmericanUniversity AppalachianStateUniversity ArizonaStateUniversity AuburnUniversity BaylorCollegeof Medicine Boardof GovernorsUniversities BostonUniversity BrandeisUniversity BrighamYoungUniversity BrownUniversity BucknellUniversity CalPolyStateUniversity CaliforniaInstituteof Technology CaliforniaStateUniversity CarletonCollegc Carnegie-Mellon University Case Western Reserve University Chico State University Chowan Collegc Clarkson University Clemson University Colorado State University Columbia University Connecticut State University Cornell University Drake University Duke University Edinboro University of Pennsylvania Embry-Riddle Aeronautical University Florida Atlantic University Florida Institute of Technology Florida State University ACNS Fordham University George Mason University George W'ashington University Georgia Institute of Technology Harvard University Indiana University Institute for Computer Applications in Science and Engineering Iowa State University Johns Hopkins Applied Physics Laboratory Johns Hopkins University Kansas State University Lehigh University Los Angeles County Otficc of Education Louisiana Tech University Lousiana State University Marquette University Massachusetts Institute of Technology Memphis State University Merit Computer Network Miami University Michigan State University Michigan Technological University Minnesota State University System Mississippi State University Monmouth College National Center for Atmospheric Research National Optical Astronomy Observatories National Radio Astronomy Observatory New Jersey Institute of Technology New Mexico State University New Mexico Tech New York University North Carolina State University North Dakota Higher Education Computer Network Northeast Missouri State University Northern Illinois University Northwestern University Nova University Oakland University Oberlin College Occidental College Ohio Northern University Ohio State University Ohio Supcrcomputer Center Oklahoma State University Old Dominion University Oregon Graduate Institutc Oregon State University Pennsylvania State University Plymouth State College Portland State University Princeton University Purdue University Computing Center Ramapo College Rensselaer Polytechnic Institute Rice University Rochester Institute of Technology Rutgers University 11

Original page 16

SanDiegoStateUniversity SanDiegoSupercomputerCenter SouthwestTexasStateUniversity SpaceTelescopeScienceInstitute St. LouisUniversity StanfordUniversity StateUniversityof NewYorkat Buffalo StateUniversityof NewYorkat StonyBrook StevensInstituteof Technology StocktonStateCollege SwarthmoreCollege SyracuseUniversity TempleUniversity TexasA&M University TexasWoman'sUniversity TowsonStateUniversity Tufts University Universityof Akron Universityof Alabama Universityof Alabamain Huntsville Universityof Arizona Universityof Arkansas Universityof ArkansasLittle Rock Universityof Arkansasfor MedicalSciences Universityof California Universityof Californiaat Irvine Universityof Californiaat LosAngeles Universityof Californiaat SanDiego UniversityofCaliforniaat SantaBarbara Universityof CentralFlorida Universityof Chicago Universityof Cincinnati Universityof Colorado Universityof Connecticut Universityof Dayton Universityof Denver Universityof Florida Universityof Georgia Universityof Hawaii Universityof Houston Universityof Illinoisat Chicago Universityof Illinoisat Urbana-Champaign Universityof Iowa Universityof Kansas Universityof Kentucky Universityof Louisville Universityof Lowell Universityof Maine Universityof Maryland Universityof MarylandBaltimoreCounty Universityof Massachusetts Universityof Miami Universityof Michigan ComputingCenter Universityof Minnesota Universityof Missouri--KansasCity 12 Universityof Missouriat Columbia Universityof Missouri-Rolla UniversityofNebraskaat Lincoln UniversityofNewHampshire UniversityofNewMexico UniversityofNorth Carolinaat ChapelHill UniversityofNorth Florida UniversityofNorth Texas Universityof Oklahoma Universityof Oregon Universityof Pennsylvania Universityof Pittsburgh Universityof PittsburghMedicalCenter Universityof RhodeIsland Universityof Rochester Universityof SouthFlorida Universityof SouthernCalifornia Universityof Tennesscc Universityof Texasat.Arlington Universityof Texasat Austin Universityof Texas at Dallas University of Texas at San Antonio University of Toledo University of Utah University of Virginia University of Washington University of Wisconsin University of Wisconsin, Milwaukee Utah State University Vanderbilt University Villanova University Virginia. Tcch Walla Walla College Washington University Wayne State University West Virginia Network for Educational Telecomputing Western Washington University Wichita State University Willamette University Worcester Polytechnic Institute Yale University Youngstown State University Government Laboratories Argonne National Laboratory Brookhaven National Laboratory Continuous Electronic Beam Accelerator Facility Fermi National Accelerator Laboratory Idaho National Engineering Laboratory Lawrence Berkeley Laboratory Lawrence Livermore National Laboratory Los Alamos National Laboratory National Cancer Institute National Institute of Standards and Technology

Original page 17

NationalInstitutesof Health OakRidgeNationalLaboratory U.S.EnvironmentalProtectionAgency WestinghouseSavannahRiverCompany Military Installations AirforceInstituteof Technology ArnoldEngineeringDevelopmentCenter BrooksAir ForceBase ChemicalBiologicalDefenseAgency DavidTaylorResearchLaboratory DefenseLogisticsAgency EglinAFB JointCommandersGroup NationalComputerSecurityCenter NavalAir WarfareCenterAircraft Division NavalOceanSystemsCenter NavalPostgraduateSchool NavalResearchLaboratory NavalSurfaceWeaponsCenter NavyPersonnelR&D Center North AtlanticTreatyOrganizaion PhillipsLaboratory(Kirtland AFB) EuropeanSouthernObservatory IDA/Supercomput.ingResearchCenter InstituteforDefenseAnalyses Instituteof ElectricalandElectronicEngineers,Inc. InteleComDataSystems MITRE Corporation North CarolinaSupercomputingCenter OpenSoftwareFoundation PerformanceSystemsInternationalInc. SURAnet TheRANDCorporation Foreign Countries Australia Canada Germany United France Japan Singapore Switzerland Taiwan Norway USArmyCorpsofEngineersWaterwaysExperiment Finland Station USArmy ResearchLaboratory UnitedStatesAir ForceAcadamey "Wright-PattersonAFB Other Organizations a2icommunications TheAerospaceCorporation TheAustinUnixUsersGroup CaliforniaEducationandResearchFederation ColoradoSuperNet,Inc. Communicationsfor North CarolinaEducation, Research,andTechnology Italy Sweden Soviet Denmark Turkey Austria South Spain Brazil Israel Portugal Korea Mexico 13

Original page 18

References 1. SunOS Reference Manual, Part Number 800-3287-10, March 1990. 2. Kehoe, Brendan P.: Zen and the Art of the h_te_et A Beginner's Guide to the Intcrnct. Revision 1.0, Feb. 2, 1992. 3. KroI, Ed: The Whole Internct User's Guide gJ Catalog. O'Reilly & Assoc., 1992. 4. PostScript Language Tutorial and Cookbook. Addison- Wesley Publ. Co., 1985. 5. Marshall, Peter: WAIS: Ttlc Wide Area Information Server or Anonymous B'7_at???. University of Western Ontario, June 1992. 6. Andreessen, Marc: NCSA Mosaic Technical Summary. NCSA Mosaic Technical Summary 2.1, Revision 2.t, May t993. 7. Berncrs-Lee, Tim; Cailliau, Robert; Groff, Jean-Francois; and PolIermann, Bernd: World-Wide Web: The Information Universe. Electron. Netw.: Res., AppI. and Policy, vol. 2, no. 1, 1992, pp. 52 58. 8. Smith, Stephanie L.: NELS 2.0 A Gencral System for Enterprise Wide Information Management. Technical Papers 9th AL4A Computing in Aerospace Conference, Part 2, 1993, pp. 1358 1365. (Available as AIAA-93- 9. Hunter, Judy; Generous, Curtis; and Duncan, Denise: NASA Access Mechanism Graphical User Interface Information Retrieval System. AIAA 93-0583, 1992. 10. Smith, Ruth S.: The NACA Collection: When Old is New Again A Status Report on the NACA Documents Project. Sci-Tcch News, vol. 16, no. 2, April 1992, pp. 15 20. 11. Lynch, Clifford A.: Information Retrieval as a Network Application. Library Hi Tech 8, no. 4, 1990, pp. 55 72. 12. Scott, Peter: HYTELNET as Software for Accessing the Internet: A Personal Perspective on the Development 14 of HYTELNET. Electron. Netw., vol. 2, no. 1, 1992, pp. 38 44. 13. Shoosmith, John N.: Introduction to LaRC Central Scientific Computing Complex. NASA TM-104092, 1991. 1.1. Hunt, Craig: TCP/IP Network Administration. O'Reilly & Assoc., Inc., 1992. 15. Network Programming Guide. Sun Microsystems, Inc., Part No. 800-3850-10, March 1990. 16. Knuth, Donald Ervin: The TeXbook. Addison-Wesley, 1986. 17. MeCaskill, Mary K.; Woessner, Linda H.; and Huffman, Jeanne P.: The Use of TEX for Technical Typesetting. 33rd Proceedings of the International Technical Communication Conference, May 1986, pp. 81 84. 18. McCahill, M.: The Internet Gopher: A Distributed Server Information System. ConneXions The Interoperability Report, Interop, Inc., vol. 6, no. 7, July 1992, pp. 10 14. 19. Schwartz, Michael F.; Emtage, Alan; Kahle, Brewster; and Neuman, B. Clifford: A Comparison of Intcrnet Resource Discovery Approaches. Comput. Syst., vol. 5, no. 4, 1992, pp. 461 493. 20. Deutsch, Peter: Resource Discovery in an Internet Environment The Archie Approach. Electron. Netw.: Rcs., Appl. and Policy, vol. 2, no. 1, 1992, pp. 45 51. 21. Kahle, Brcwster; Morris, Harry; Davis, Franklin; Tiene, Kcvin; Hart, Clare; and Pahner, Robert: Wide Area Information Servers: An Executive Information System for Unstructured Files. Electron. Netw.: Res., Appl. and Policy, vol. 2, no. 1, 1992, pp. 59 68. 22. Maly, Kurt J.; Fox, Edward A.; French, James C.; and Selman, Alan L.: Wide Area Technical Report Server, Old Dominion University Computer Science Technical Report TR-92-,1,1_ 1992. 23. Goldfarb, Charles F.: The SGML Handbook. Oxford University Press, 1990.

Original page 19

Form Approved REPORT DOCUMENTATION PAGE OMB No. 0704-0188 Public reporting burden for this collection of information is estimated to average I hour per response, including the time for reviewing instructions, searching existing data sources, gatherin and ma ntainlng the data needed, and completing and reviewing the collect on of information Send comments regarding this burden estimate or any other aspect of this collectiong of information, including suggestions for reducing this burden, to Wash ngton Headquarters Services. Directorate for Information Operat ons and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302, and to the Office of Management and Budget, Paperwork Reduction Project (0"/04-0188). Washington, DC 20503 , 1. AGENCY USE ONLY(Leave blank) 2. REPORT DATE March 1994 4. TITLE AND SUBTITLE 3. REPORT TYPE AND DATES COVERED Technical Memorandum 5. FUNDING NUMBERS Electronic Document Distribution: Design of the Anonymous FTP Langley Technical Report Server 6. AUTHOR(S) Michael L. Nelson and Clretchen L. Gottlich 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) NASA Langley Research Center Ilampton, VA 23681-0001 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) National Aeronautics and Space Administration Washington, DC 20546-0001 11. SUPPLEMENTARY NOTES 12a. DISTRIBUTION/AVAILABILITY STATEMENT Unclassified Unlimited Subject Category, 61 13. ABSTRACT (Maximum 200 words) An experimental electronic dissemination project, WU 505-90-53-02 8. PERFORMING ORGANIZATION REPORT NUMBER L-17355 10. SPONSORING/MONITORING AGENCY REPORT NUMBER NASA TM-4567 12b. DISTRIBUTION CODE the Langley" Technical Report Server (LTt/S), has been undertaken to determine the feasibility of delivering Langley technical reports directly to the desktops of researchers worldwide. During the frst 6 months, over 4700 accesses occurred and over 2400 technical reports were distributed. This usage indicates the high level of interest that researchers have in performing literature searches and retrieving technical reports at their desktops. The initial system was developed with existing resources and technology. The reports are stored as files on an inexpensive UNIX workstation and are accessible over the Internet. This project will serve as a foundation for ongoing projects at other NASA centers that will allow for greater access to NASA technical reports. 14. SUBJECT TERMS 15. NUMBER OF PAGES 17 Anonymous FTP; Technical Reports; NASA Langley Research Center; Electronic Document Dist.ribution; WAIS 16. PRICE CODE A03 20. LIMITATION 17. SECURITY CLASSIFICATION 18. SECURITY CLASSIFICATION 19. SECURITY CLASSIFICATION OF REPORT OF THIS PAGE Unclassified Unclassifietl NSN 7540-01-280-5500 OF ABSTRACT OF ABSTRACT tandard Form 298(Rev. 2-89) Prescribed by ANSI Std Z39-1B 298-102

Original page 20

i i 7