The Distributed Access View Integrated Database (DAVID) System, which was adopted by the Astrophysics Division for their Astrophysics Data System, is a solution to the system heterogeneity problem. The heterogeneous components of the Astrophysics problem is outlined. The Library and Library Consortium levels of the DAVID approach are described. The 'books' and 'kits' level is discussed. The Universal Object Typer Management System level is described. The relation of the DAVID project with the Small Business Innovative Research (SBIR) program is explained

Jacobs, Barry E.

English

NASA Technical Reports Server

N91-23037
DISTRIBUTED ACCESS VIEW INTEGRATED DATABASE
(DAVID) SYSTEM
Barry E. Jacobs
Code 934
Goddard Space night Center
Greenbelt, MD 20771
Introduction
Due to the diversity of computers, operating systems, management systems, network protocols, etc., NASA
space sdentists have to learn many different access methods ".morder to obtain data..For.c__ple, _
I_ASA's Space Astrophysics Program, Astrophysics ob_.atones suc_, a_ the mternauonal U+ltravtotetr
Explorer (IUE), Hubble Space Telescope, Ganl.ma Ray ut_ervatory (t_,ttu.) et_.generauy nave onto
more data centers for the analysis and distributton ot oata. tne neterogenetty ox tts aata centers makes
Astrophysics multi-mission research almost impossible.
The Distributed Access View Integrated Database (DAVID) System, which is the subjec.t.ofotl_, -
paper, is a solution to the problem. See Figure 1. The DAVID System _ .oeen aoopteo .oy P_A._A S,
Astrophysics Division for their Astrophysics Data System and r.epresents one o tthe mostextenslve nat)on,m_
testbeds of heterogeneous distributed computing systems. Although the DAVID _ystem was ongmauy
built to uniformly access databases, it is. currently b_'m_.._neralized.to other object ty_pes s_uch._t
spreadsheets, images, manuscript, graphics, etc. t n.e .DA. VLO sonware tS m me process o[ ocmg r_uu t
by the private sector for adoption by other rqA_A msctpnnes.
The DAVID approach to the heteroseneons distrt"outed systems problem is +at four. !evels:o See
Figure 2. At the lowest level, we develop umversal object type m .a_gement systems toprovme un_. orm
access to heterogeneous database, "nn.a__es, spreadsheet, manuscrtpt, et5_ man.agement s_tems._At me
_,.,_,_n,4 h,ve/we deve[cm "book" and "kit" management systems to provtae untzorm access tu _ltg;;_ttLU
_sVof data'objec-ts_Atrthe third level, we develop ".libr.art"es"to provide .u_.,ort_, access to a mc_, a{ea
....................,,-twnrlr¢,_f enmnuters ct3ntam_g"" = "books.'. "kits',. ana. other, oata oo'eczsj. .At me iounn lever, we oevetop
consortiums of libraries to provicre access to sets of llbrane.s.
An outline of the paper is _ follows. In S.e_i."on 1,..we outline tlae.,heterogeneous, comp_oneon_sl_ef
the Astrophysics program.. InSectton 2, we dcs_tm _¢ .Laorar_, aJzaLmrar2/...__ jnsortz.unzffve_;v,, t_, '
DAVID approach. In Section 3, we mscuss me uoozs ann z_JtSlevel in _¢cuon,% w_ u_ata ,t.,_ u,_. w_ ,.,+,,.
Object Type Management System level. In Section 5, we explain the relation of the DAVID. project .wi.'th
the Small Business Innovative Research (SBIR) Program. We conclude the paper m Sectmn 0, wttl_ a
summary.
The Heterogeneous Astrophysica Program
NASA's Astrophysics program provides a good example of the system heterogeneity problem. We briefly
outline some of the heterogeneity.
The Infrared Processing and An. all_ " Center (IP,AC) at C .aliforn:i'aII_titute of T_de_Clo clcl_omm_pgTsS
data from infrared sensors such as the mtrarea :,atemte (IRA_). lk'At._ has t..yoer anu _ p ,
Cyber and Unix Operath_ Systems, IM/DM data.base, management, s]_tem, and _temet and D?_R_Ne_
communications. The data includes IRAS observataon 10gs (aata o .ases),ttt2,_ pr .oou.cts (oa}au_cs),7-._ _
eels IRAS documentauon manuscripts), aria tt_,_ sottwax¢imagery (images), ERAS spectra (spreadsh ), ( "
The Smithsonian Astronomical Observ.a...tory(SAO) at Harvar.d U_versi_m_ data ofrom the
hlgh-energy sensors such as the Einstein or High-Energy Astronomtcai ul_rvato,ry (,ttr._u). _ze_
VAX, Sun and Cyber computers, VAX/VM.S an.d Unix Opera -.tt_ ,_yst,ez_. _es__m_u.._a_,.. _m_em_nt.
system, and Internet .and _ Net co ,ram trot._n.om.. Ilm _ mcluaes .t__. t.em._o2_auun 2_u=,t:_
m lm nn r'41zstcm ,,l.w,t_u- _apl_,a_._u_,vto],bases_ Einstein nroducts fdatabases), mnste agery ( ages),
i_. r . " " " " @Einstein do,azmentalaon (manmcnpts), and _inttem softwar .
137
https://ntrs.nasa.gov/search.jsp?R=19910013724 2020-03-19T17:40:06+00:00Z
PROBLEM:
NASA space scientists have to learn many different
access methods in order to obtain data.
SOLUTION:
DistrTbuted Access View Integrated Database (DAVID)
• Adopted by AItrophyai'(= Oivinron
(_Z) _'o! HllJI" _l_Jlrlj_)lJCl O;_'Q
S_tem.
• M#lrt extensive national 1ell'bed of
hetm-c_eneoum dtMributed
comput|ng _,=fems.
• CurnBnlly being 9enerallzed Io other
obIKl _pes such os sprocldgheehJ.
lrn_ges, monuecdpte, grgphlcs, etc.
• CurrenN/ being reburlt by title
prl)vote sector for odopffon by
olihor NASA dl'mclpllnl.
DAVID Installation Sites:
Astrophysics Data System
_mbod
Figure 1.
DAVID Approach
Distributed
Level Model
To The
Sysfem
Heterogeneous
Problem
Examples
Co_o_'Lww_ OJ"Z,'_br¢'ri,es:
Aggregate Set of Related Libraries
ADS. High-Energy,
Gamma Ray
Libra_ee:
Collections of Holdings
NSSDC. IUE RDAF.
IPAC, SAG, StSCI
Book, & _{t Objec_e:
Aggregate Set of Related Objects
Library Catalog Book,
IUE ObservatJon Book,
IUE Software Tools Book,
Astrophysics Research Kit
UnCue're¢_ Objee¢ Tb,'pe
Provides Uniform Access to
Heterogeneous Objects
Universal Database
Management System,
Universal Image
Management System,
Universal Manuscript
Management System
Figure 2.
138
The International Ultraviolet Explorer (IUE) Regional Data Analysis Facilities (RDAF) at the
Goddard Space Flight Center and at the University of Colorado manage data from the International
Ultraviolet Explorer mission. The RDAFs have VAX, Sun and IBM computers, VAX/VMS, Unix, and
IBM Operating Systems, Ingres, IBM database management system, and Internet and Dec Net com-
munications. Tlae data indudes IUE observation logs (databases), IUE products (databases), IUE spectra
(spreadsheets), IUE documentation (manuscripts), and IUE software.
The Space Telescope Science Institute (STScI) at the Joh nsHopkinsUniversity manages, data_I_
the Hubble Space Telescope (HST). The STScI has V AX.ano _un ann t_yoer _mputers, VAA/ J
and Unix Operating Systems, Sybase .and Bfitten-Lee database m ana_:ement s_ms, ja_.a _n_ernke_an_.
Dec Net communications. The data incluaes HbI ooservauon |ogs taataoases), rt3_ prouuc,b _uataua_v ),
HST spectra (spreadsheets), HST documentation (manuscripts), and HST software.
The National Space Science Data Center (NSSDC) at the Goddard Space Flight Center manages
data from a number of astrophysics and non-astrophysics missions. The NSSDC has VAX, Sun, IBM, and
Cyber computers, VAX/VMS, IBM and Unix Operating Systems, Ingres, Oracle, Sybase and Britten-Lee
database management systems, and Internet and Dec Net communications. The data includes multi-
mission observation logs (databases), data products (databases), spectra (spreadsheets), documentation
(manuscripts), and software.
Libraries and Library Consortiums
The DAVID approach, models a local area network as a library and a set of local area networks as a
consortium of libraries. See Figure 3.
Each local area network of computers is modeled as a library in which each of the machines is a
"room". One particular room, the "main room", serves as a gateway into the library. When one lo.gs on to
the main room and enters the command "dlib, one gets the Library Directory menu which leads the user
to the Main Room (described below), Tutorials, Reading Rooms (computers for library holdings), Per-
sonal Library Rooms (computers for user holdings), and Management Rooms Menus (computers for
staff holdings).
When the Main Room option is chosen, the user sees the Main Room Menu. This consiStSnOf
submenus f_r A dministrative Desk (library cards_ bul_etin t)_ara_ mai_ pn_ne_ suggest_ns_ e[c.)_ ttexere ce
Desk (names, phone and forms to reference librarians), Library Catalogue (database of local library
holdings), Circulation Desk (forms for borrowing off-line holdings), Reproduction (forms for reproduc!ng
off-line holdings and software for reproducing on-line holding), U_on Library Desk+(access.to umon
catalogues and facilities for consortiums), and Remote Libraries Desk (access to remote noranes).
A local library may be a member of one or more consortiums of libraries. A library consortiums
is a organization of participating libraries which share each other's resources. One of the functions of a
library consortiums ts to provide a union catalogue of all of the holdings over all of the member libraries.
A user can access a union catalogue of a consortium and determine which member has the holding. He
can then ask his local library to help him obtain obtain access to it.
For examnle, in the Astrophysics examnle, the library representing the Center For Astrophysics
!CFA) could belong to several consortiums, t_orexample, "X-Ray", "High-Energy', "Astrophysics", and
Multt-Disciplinary'. Then if a user at CFA wants a holding not at CFA he can consult one or more ol
the union catalolgues of the different consortiums. He would then locate the holding and ask his local
librarian to obtzan access to the holding.
Books and Kits
The DAVID approach, models an aggregate of relate data as a book and a kit.
A book is an aggregate data structure which is divided into logical units called chapters and physical
units called components. An example of a book is given in Figure 4. for theBookof IUE Obse,rvations.
Here each chapter represents one of the 80,000 observations taken by lute. _ne tut_ ooox has as
components- a title page (manuscript), a preface (manuscript), a table of contents (database), chapter
components including- observation aescriptions (manuscript), proposals (manuscripts), literature refer-
ences (database), raw image (images), extended-line-by-line spectra (spreadsheets), observation scripts
139
I Libraries and Library Consorfiums I
APPLICATIONS
I Astrophysics II High-Performance Computing] IGIoba I ChangeJ
Library Directory
1) MoM Room
2:1Tuterk_l,,
3) R_dtng R_
*4 _ _ Ro_m
5) Man_iernent Rooerm
On/Oil Line
J Type Clmse,main
r
union library Iwideor_o
conaortium
Main Room'_ I
__._,;m_o.o..,.ii I ""_'_'_('°°'')I
2) Reference ONk II 01300
3) Lbrary CoMIog II
4} Circufefon D._ II main
unlm I.Brery val_. II
"'_'_"_" °'11 / library
I network
I
c_._, (_m,>I
;brary
IOCQI area
networks
LIBRARY PARADIGM
• dotoboeee
• ipr mdeheeta
• manuscript,
• ;rrmge e
• graphics
• mops
• oudioviluoll
Iot_om tools
ser;alu
k[tl
books
expcrt_
objectl
Figure 3.
IUE Observafion Book I
IUE Oblervatlons
:__ sew
__=, °.o . . ..._..°..,_,
delcrl ................... '_ '_a_ ,mogol mec_m "_pecb'o specloro imoq4m scrip_-''--me__-- .fills ob._.
IN... Bill... E]I3..._B.. I_... _...XSxl_...BEI...Ii
IN _ [_ Ira, theoourueeo/dlcUonarlee
n- g_
Figure 4.
140
(images), indexes including object id, object class, rectangle. In addition, each of the index components
has a thesaurus/dictionary database. Another example of a book is the IUE Software Tool Book where
each chapter represent one of 900 software programs written expressly for IUE data. A t_.d example is
the Local Library Catalogue Book where each chapter represents one ot the notoangs at me tocat area
network.
A kit is an a_regate data structure which is just divided into PhySical units called components. An
example of a book ts _iven in Figure 5. for _e IUE Software Too, Is kit for managing IUE softw.are. The
IUE Software Tools kit has as components- a tatle page _manuscnpt), a prelace _man_cnpt), requtrements
document (manuscript), users guide (manuscripts), high-level design document _manuscnpt), system
administrators guide (manuscript), users comments (manuscript), reference manual (book_, low-level
internals (book), installation (book), source code (book), object code (book), testing plan [uook), and
software tool (book). Another exam. pie of a kit is an Astrophysics Rese,_..ch Kitwhich represents t_n_
Research problem in Space Astrophysics aria WhOSe components are suomts eacn representing a su -
problem of the original problem.
Universal Object Type Management Systems
The DAVID approach, make use of universal object type management systems.
A Universal Object Type Management system allows one to retrieve, read and operate on object
of a particular object type independent of the subtype and internal format. Figure 6. contains examples
of object types for which universal object type management slcstems. _e important; For exanaple, a un_ersal
database management system allows one to operate on oataDases moepenoent otme type _e.g., relauonaJ,
hierarchical, and network) and internal format (e.g., lngres, IM/DM, S_/base, IMS, etc.). A universal
manuscript management system allows one to operate on manuscripts independent of the type (e.g.,
structured, unstructured) and internal format (e.g., ASCII, Tex, Troff, Word Perfect, etc.). A universal
image management system allows one to operate on images independent of type (e.g., level 0, level 1)
and internal format (e.g., TIFF, FITS, IRAF, etc.).
DAVID And the SBIR Program
The DAVID project has made strong use of the Small Business Innovatve Research (SBIR) Program. A
number of successful SBIR projects are described here.
Heterogeneous Network Access by Digital Analysis Corl_ration of Reston, Virginia. The purpose
of this project was the development of a _unif."orm layerthatcan be put o.ntop or.heterogeneous .ne[wor_
alternatives such as TCP/IP, DEC Net, Bit Net, etc. r.acn suDnet provaaes oaslc networx services ana
hops between subnets are handled by servers at the gateways.
Heterogeneous Interface Building by FL Wan derman, and A_oc.,.iates of S!aten Island, New York;
The l_urpose of this project is the developmenta so.ttware tlaat wm tacmtate oevesopment ot mterta_s ox
data6ase management systems and arbitrary tiles mto.tlae, N.A_A aeyelol_a umver_.t)ataoase _anf
agement S_tem. The software will be playing a central rote m me estatmsnment ot major repomtory o
Astronomical Catalogues at the NSSDC.
Universal Index Management Systems by.Adv.anced Communication Te.chnology Incorporated 3f
Silver Spring, Maryland. The purpose of this project ss the development o.I aumvers_.moex manageme [
system. The software will allow users and system builders to construct maexes oi mtierent types .tone,
two, three dimensional, etc) and different formats (B-trees, R-trees, hash, etc.);, The software wm t_e
playing an important role in speeding up access of data in the Astrophystcs Data _ystem.
Universal Software Tool Management Systems by HSA Incorporated of Sugar Land, Texas. The
purpose of this project is the development of a universal software tools m a.n.a_gementsystem tor mana_ng
software over distrtbuted systems. Each software tool is represented as a tat m a mmnar way mat me tut_
Software Tools Kit above was described. The software will be playing an important role in the management
of software in the Astrophysics Data System.
141
IUE Software Tools Kit
Legend
mGnuKdpt
_j_t
N=
R_
Tnl.£ P_rAC£
PAO£
R£QUIR[ME:NTS USERS HtGH- I..L"_L SYEIl[U t,I_ERS LIIEXATUR[
DOCUkEHT OUIOE OE_SI_I AOketeSTRA'rot_ COUt_NTS REFI[RENCL"S
_X_UVEHI" GUIDE:
RE71mE]_ LGW-t_rVEL I/ST&LATION
K_U,_. IN11_KiLS 8OaK
IIIOOK IiOOK BOOK BOOK el)OK
F_n_'e5.
Universal Object Type Management Systems I
databa=e /older binder to_-_t
p_o album IndexRt atlas
oucliov_la *erlal_t
t_nk_nk
I I
bo_:kset kib,et
Figure 6.
142
Universal Object Type Management Systems by REIAs_._ a.tesof McLean, Virginia. The pur_s_
of this project is the development of a man.ageme.nt system xor oral.am g other m a_aa_emem sys!ems__ac,
management system is represented as a rat winch. _n_ams remevai _nw_e too_ .ana request "_e
tools. The software will be playing an important role m me oevelopmem ox omer umversat uoject yp
Management Systems.
Universal Book Management Systems by AdvancedAppfi.cations Corporation of Po!omac, M_r
yland. The purpose of this proje.ct, is the development o.t a un_..r_., t_o_r,s m anagementsystemboIOr
managing book objects. Each book is r.eprese.ntea m a smlu.ar way mat me Iu_ u o_ry. a_lon_oo_ ac_.
was described. The software will be playing an tmportant role m me management oxaata m me Astropnys_cs
Data System.
Summary
The Distributed Access View Integrated Database (DAVID) System, which has been adopted by
the Astrophysics Division for their Astrophysics Data System, is a solution to the system heterogeneity
vroblem. In Section 1, we outlined the heterogeneous components of the Astrophysics problem. In S_tion
we described the Libra,. and Library Co.usortium leve..ls of the DA.VID aj_proach_In Section _e_ _
discussed the Books and Kits level. In Section %we aescrtoea me umver .S_dUoJ..e_ .type m anagcm_ t
System level. In Section 5, we explained the relation of the DAVID project WZththe _man t_usmess
Innovative Research (SBIR) Program.
143


Distributed Access View Integrated Database (DAVID) system

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