Directory UMM :Data Elmu:jurnal:E:Environmental Management and Health:Vol09.Issue1.1998:

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Enviro nme ntal Manage me nt and He alth

9 / 1 [1998] 2 7 –3 1 © MCB Unive rs ity Pre s s [ISSN 0956-6163]

REMSSBOT technical implementation

M aarten Galle

Pro je c t Le ade r/ Co ns ultant IT, EDS, The Ne the rlands

REMSSBOT overcomes the technical problems that arise when you need to access regional environmental data that are located at several data providers that have different technical infrastruc-tures. The user can search for data defi ning a who, what, where and when selection. The result of this selection can be information about the data, a reference to those data or access to those data in a structured format. REMSSBOT is an Object Oriented toolkit implemented in Visual Wave and in Forté. The used technology is based on CORBA 2.0 for communi-cation and is multi-platform. User interfaces are in Windows and WEB browser. REMSSBOT can be used as a toolkit for implementation in other regions.

Introduction

In t h is a r t icle t h e t ech n ica l im p lem en t a t ion of RE M SSBOT w ill b e d es cr ib ed .

F ir s t of a ll a su m m a r y of t h e m a in fu n c-t ion a l r eq u ir em en c-t s is lis c-t ed , a s w ell a s c-t h e im p lica t ion t h ey h ave for t ech n ica l s olu t ion .

Why REM SSBOT?

As ea r lier d efi n ed , RE MSSBOT in t en d s t o b e a s olu t ion for t h e p r oblem of s ea r ch in g for en v ir on m en t a l d a t a a n d a ccess in g t h os e d a t a . E n v ir on m en t a l m a n a gem en t h a s oft en h a d a region a l b a sis: t h e ca t ch m en t of a r iver, a sea or a n a r ea w it h a ir p ollu t ion p r oblem s. T h e p r op er t y of en v ir on m en t a l p h en om en a is t h a t t h ey r a r ely st op a t a d m in is t r a t ive b or d er s. T h is is in con t r a s t w it h m on it or in g of en v i-r on m en t a l d a t a t h a t is n oi-r m a lly oi-r ga n ised on a n a d m in ist r a t ive b a sis. So s olv in g a n en v i-r on m en t a l p i-r oblem m ea n s a lso ci-r os sin g a d m in is t r a t ive b or d er s.

In E u r op e n o s t a n d a r d isa t ion exis t s in en v ir on m en t a l m on it or in g sy s t em s. Alt h ou gh som e in it ia t ives t o st a n d a r d ise en v ir on m en t a l sy st em s h ave b een t a k en , in r ea lit y ea ch or ga n isa t ion h a s it s h a r dw a r e a n d s oft w a r e en v ir on m en t a n d it s ow n w ay of p r oces s in g t h e d a t a . T h e r es u lt s of m on it or -in g a ct iv it ies a r e s t or ed -in a d a t a b a se. It is t h e t a s k a n d t h e ch a llen ge of a r es ea r ch er t o fi n d t h e r igh t d a t a b a ses a n d t o collect t h e n eed ed d a t a fr om t h ose d a t a b a ses. To m a k e life for t h is r es ea r ch er som ew h a t ea s ier t h e RE M SS-BOT p r oject st a r t ed .

Functionality of REMSSBOT

RE M SSBOT h a s t h e follow in g fu n ct ion s a n d ch a r a ct er is t ics:

• By u s in g RE M SSBOT a u ser ca n sea r ch for d a t a by s p ecify in g t h e s elect ion cr it er ia . T h es e cr it er ia a r e ca lled t h e “Wh o”, “Wh a t ”, “Wh er e” a n d “Wh en ” cr it er ia , t h e “W4” s elect ion .

• Beca u s e d a t a b a ses a r e m a n a ged by d iffer -en t or ga n isa t ion s in d iffer -en t cou n t r ies w it h oft en d iffer en t la n gu a ges, m u lt i la n -gu a ge fa cilit ies h ave t o b e in cor p or a t ed . T h is is im p or t a n t n ot on ly for t h e u s er in t er fa ce, bu t even m or e for t h e n a m in g of

t h e sea r ch ed d a t a : “Oxygen ” is ca lled “Sa u er st off ” in Ger m a n y a n d “Zu u r st of ” in T h e N et h er la n d s. So t o fi n d a ll of t h em , t h e t er m “Oxygen ” h a s t o b e t r a n sla t ed . • As a r esu lt of t h e p r ev iou s it em a n d b eca u se

of t h e n eed for a st a n d a r d a n d com p let e st r u ct u r e of t er m s, t h e CDS is b a sed on t h e E E A-t h es a u r u s.

• Sever a l m et h od s of sea r ch in g a r e in cor p or a t ed : h ieor a or ch ica l, a lp h a b et ica l a n d gor a p h -ica l. T h e h ier a r ch -ica l m et h od s sh ow s a t r ee of t er m s a n d t h e u ser ca n st e p t h r ou gh t h is a s t h r ou gh t h e d ir ect or y s t r u ct u r e on a P C. T h e a lp h a b et ica l m et h od ju s t sh ow s a sor t ed list of t er m s. For t h e “Wh er e” cr it e-r ia a ge-r a p h ica l select ion m et h od is a lso ava ila ble. By click in g on a m a p t h e u ser ca n select t h e d esir ed a r ea .

T h e r esu lt of t h is “W4” select ion is a list of ser v ices t h a t ca n b e ob t a in ed , t h e “ser v ices” (RE MSSBOT F V s er v ices ). T h e R-ser v ices ca n b e d iv id ed in t h r ee ca t e gor ies: 1 R-In fo;

2 R-P r od u ct (b ot h u n st r u ct u r ed d a t a ); a n d 3 R-P r ocess (st r u ct u r ed d a t a ).

R -In fo is a s im p le d escr ip t ion of w h er e t h e d a t a ca n b e fou n d , ju st a r efer en ce t o a p er son or or ga n isa t ion t h a t h a s t h e d a t a ava ila ble, p r ob a b ly lik e a b ook on t h e sh elf.

R Pr od u ct offer s, a p a r t fr om t h e d escr ip -t ion , a r efer en ce -t o -t h e d a -t a -t h em s elves, so t h a t t h ey ca n b e a ccess ed d ir ect ly. E xa m p les a r e fi le n a m es or a URL t o a WE B sit e. For RE M SSBOT t h es e d a t a a r e con sid er ed a s u n st r u ct u r ed : RE MSSBOT con sid er s t h e d a t a a s on e p iece (e.g. a fi le) w it h ou t t a k in g t h e con t en t s in t o a ccou n t .

R -Pr ocess is t h e m ost com p let e s er v ice of RE MSSBOT. It gives a cces s t o st r u ct u r ed d a t a in a d a t a b a se, fr om w h ich t h e r eq u ir ed d a t a ca n b e s elect ed a n d for w h ich a u ser ca n d efi n e con st r a in t s.

Technical choices

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Maarte n Galle REMSSBOT te c hnic al imple me ntatio n

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follow in g d iffer en ces in t h e Re gion a l E n v i-r on m en t a l Da t a P i-r ov id ei-r s (RE DP ). • H a r dw a r e p la t for m ;

• Op er a t in g s y s t em ;

• Da t a b a s e Ma n a gem en t Sy st em (DBM S); • Da t a s t r u ct u r e;

• Da t a b a s e a ccess: SQL or a s p ecia l Ap p lica -t ion P r ogr a m m in g In -t er fa ce (AP I); • Com m u n ica t ion : con n ect ed t o LAN, WAN,

In t er n et , d ia l u p lin e, et c.;

• Secu r it y : som e a r e op en , ot h er s a r e lock ed b eh in d fi r ew a lls a n d p r oxy ser ver s. To m a k e t h e t ech n ica l ch oices t h e follow in g t ech n ology is ch osen in RE M SSBOT.

M ulti-platform

To b e a ble t o a ccess a ll exis t in g d a t a p r ov id er s RE M SSBOT m u st r u n on a lm ost ever y exis t in g com p u t er, s o a t lea st on Un ix, OS2, W95, N T a n d M a c.

Object-Oriented technology

We h ave ch osen a n Ob ject -Or ien t ed (OO) a p p r oa ch . N ot b eca u s e OO is fa s h ion a ble, bu t b eca u s e w e see r ea l a dva n t a ges in t h e OO a p p r oa ch for RE MSSBOT. T h e in it ia l d em on -s t r a t or -s w ill n ot b e t h e fi n a l -sy -s t em -s. In fu t u r e RE M SSBOT is exp ect ed t o b e a p p lied in m a n y ot h er s y s t em s a s a t oolk it . OO is in it ia lly n ot ch ea p er or b et t er t h a n a cla s s ica l a p p r oa ch , bu t w h en a sy s t em is ext en d ed or a d a p t ed , t h e OO a p p r oa ch lea d s t o b et t er p oss ib ilit ies for r eu se of cod e a n d cr ea t ion of bu ild in g block s w h ich w ill lea d t o low er cos t .

Common Object Request Brokering Architecture (CORBA)

RE M SSBOT con n ect s sy s t em s t h a t a r e geo-gr a p h ica lly d ist r ibu t ed over s ever a l loca t ion s t h a t m u s t b e con n ect ed u s in g su it a ble com -m u n ica t ion p r ot ocols. For t h e OO a p p r oa ch w e ch ose CORBA 2.0. CORBA st a n d s for Com -m on Ob ject Req u est Br ok er in g Ar ch it ect u r e. CORBA is t h e on ly ven d or in d e p en d en t st a n -d a r -d ava ila ble on t h e m a r k et . It is -d evelop e-d by OM G (Ob ject M a n a gem en t Gr ou p ), a n d is a d op t ed by X/ Op en a n d OSF (Op en Soft w a r e Fou n d a t ion ), t h e t wo lea d in g op en sy s t em s con sor t ia , n ow con solid a t ed in “T h e Op en Gr ou p ” t h a t wor k t oget h er t o d eliver t ech n o-logica l in n ova t ion s a n d w id e-sca le a d op t ion of op en s y s t em s sp ecifi ca t ion s. M a n y im p le-m en t a t ion s of CORBA exis t , t h a t le-m ea n s le-m a n y d iffer en t la n gu a ges (lik e Sm a llt a lk , J ava , a n d For t é) im p lem en t ed by d iffer en t ven d or s. CORBA u ses IDL (In t er fa ce Defi n it ion La n -gu a ge) a s t h e in t er fa ce s p ecifi ca t ion b et w een t h e t wo s y s t em s.

WEB technology

RE M SSBOT h a s ch osen WE B-t ech n ology t o m a k e u se of t h e u p com in g In t er n et a n d In t r a n et in fr a st r u ct u r e. T h is a lso gives t h e p ossib ilit y of m a k in g en v ir on m en t a l d a t a ava ila ble for t h e gen er a l p u blic, a s it is on e of t h e u ser r eq u ir em en t s of RE MSSBOT.

Programming environment

RE M SSBOT is im p lem en t ed in t wo p r ogr a m -m in g en v ir on -m en t s. In t h e r e gion s of Sch eld t (T h e N et h er la n d s a n d F la n d er s, Belgiu m ) a n d At t ica (Gr eece) RE M SSBOT is im p lem en t ed in Vis u a l Wave, a Sm a llt a lk im p lem en t a t ion a n d DST (Dist r ibu t ed Sm a llt a lk ). In P iem on t e (It a ly ), For t é is u sed a s t h e p r ogr a m m in g en v ir on m en t .

REMSSBOT system architcture

T h e RE MSSBOT sy st em a r ch it ect u r e is given in F igu r e 1. Alt h ou gh n ot a ll sy s t em p a r t s a r e im p lem en t ed in a ll r e gion s, t h e a r ch it ect u r e gives t h e gen er a l p ict u r e on w h ich t h e t h r ee d em on st r a t or s a r e b a sed .

T h e d escr ip t ion b elow is b a sed on t h e Sch eld t d em on st r a t or, b eca u se it con t a in s a ll t h e p a r t s of t h e a r ch it ect u r e.

E a ch r ect a n gle in t h e fi gu r e r e p r esen t s a sy st em p a r t , r u n n in g on a com p u t er. In p r a c-t ice ic-t is p os sible c-t o com b in e sever a l p a r c-t s on on e com p u t er.

T h e sy st em p a r t s a r e d iv id ed in t o t h r ee gr ou p s:

1 Clien t s/ F r on t en d ; 2 Cen t r a l P a r t s;

3 Re gion a l E n v ir on m en t a l P r ov id er s/ Ba ck en d .

Client/ Front end

T h e “Clien t / F r on t en d ” gr ou p con t a in s t h e sy st em p a r t s w h ich sh ow s t h e GUI: • a Win d ow s GUI;

• a GUI for a WWW Br ow ser.

Bot h give t h e u ser con t r ol for b r ow sin g t o t h e t h esa u r i, m a k in g a select ion , list in g ava ila ble p r od u ct s a n d d ow n loa d in g p r od u ct s.

Central Parts

T h e Cen t r a l P a r t s gr ou p con t a in s: • t h e RE MSSBOT H TTP Ser ver a n d t h e

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Wave Ser ver a p p lica t ion , w it h p r a ct ica lly t h e sa m e fu n ct ion a lit y a s t h e SIS/ CDS on ly w it h a d iffer en t GUI.

T h e CDS Da t a b a se Ser ver con t a in s t h e CDS d a t a b a s e. T h is d a t a b a se st or es :

• m et a in for m a t ion over t h e p r od u ct s w h ich ca n b e fou n d by RE M SSBOT;

• t h es a u r i t o b r ow s e in (t r ees, lis t s ), a n d m a k e s elect ion s ;

• a d d it ion a l in for m a t ion t o d ow n loa d t h e p r od u ct s.

T h e CORBA N a m in g Ser v ice con t a in s a cen -t r a l lis -t of a d d r es s es of r em o-t e a ccess ible sy s t em s. T h e RE DP in t er fa ces r e gist er t h em -selves t o t h e CORBA N a m in g Ser v ice, s o CDS clien t s ca n a s k for t h e a d d r es s in or d er t o b e a ble t o s en d a n elem en t a r y s er v ice r eq u est (E -ser v ice) t o t h e a p p r op r ia t e RE DP in t er fa ce.

Regional Environmental Providers/ Back end

T h e Re gion a l E n v ir on m en t a l P r ov id er s/ Ba ck en d gr ou p con t a in s t h e s y s t em p a r t s w h er e t h e a ct u a l p r od u ct s (en v ir on m en t a l d a t a ) a r e st or ed :

• RE DP (Re gion a l E n v ir on m en t a l Da t a P r ov id er );

• RE DP in t er fa ce.

T h e RE DP is a n exist in g d a t a b a se (lik e DONAR or t h e VMM d a t a b a se in t h e Sch eld t r e gion ). It h a s it s ow n d efi n it ion s a n d st r u c-t u r es. RE MSSBOT on ly m a k es c-t h ese d a c-t a a ccessible. E a ch d iffer en t t y p e of RE DP n eed s a sp ecifi c RE DP in t er fa ce.

T h e RE DP in t er fa ce is a Vis u a l Wor k s Ap p lica t ion t h a t r eceives E -s er v ices fr om t h e CDS a n d t r a n s la t es t h em t o a RE DP Sp ecifi c Qu er y, a sk s t h e RE DP a n d r et u r n s t h e r esu lt t o t h e CDS.

T h e Re gion a l E n v ir on m en t a l WE B sit e H TTP Ser ver is a n or m a l H TTP Ser ver w it h (r e gion a l) en v ir on m en t a l fi les or p a ges. A r efer en ce t o t h ese p a ges is d escr ib ed in t h e CDS a n d is ca lled a n R -Pr od u ct.

REMSSBOT services

T h e st r u ct u r e of t h e RE M SSBOT ser v ices is given in F igu r e 2.

T h e r esu lt of a W4 select ion is a p r od u ct t h a t ca n b e a sin gle ser v ice, a com p osed ser -v ice, a Rem s sb ot -In fo or a Rem ssb ot -P r od u ct . A sin gle ser v ice is r efer r ed t o on e E -ser v ice t h a t con cer n s on ly on e d a t a p r ov id er. A com p osed ser v ice is r efer r ed t o m or e t h a n on e E -ser v ice. A com p osed s er v ice r esu lt s in d a t a t h a t or igin a t e fr om sever a l d a t a p r ov id er s a n d t h a t a r e com b in ed in on e t a ble.

In t h e a ct u a l d em on st r a t or s com p osed ser v ices a r e n ot yet im p lem en t ed .

Hardware implementation

To give a n exa m p le of a h a r dw a r e con fi gu r a t ion , t h e ou t lin e of t h e Sch eld t im p lem en t a -t ion is p r esen -t ed in F igu r e 3.

T h e Sch eld t d em on st r a t or is s it u a t ed a t t h r ee loca t ion s: Mid d elbu r g DZL, Mid d elbu r g RIKZ (T h e N et h er la n d s) a n d Aa lst (Belgiu m ). At a ll t h r ee loca t ion s t h e u sed com p u t er s a r e con n ect ed t o Loca l Ar ea N et wor k s. T h e con -n ect io-n b et w ee-n t h e t wo loca t io-n s i-n Mid d el-bu r g is r ea lised by a n exist in g Wid e Ar ea N et wor k . T h e In t er n et m a k es t h e con n ect ion t o Aa lst . Also u s er s ca n b e con n ect ed t h r ou gh t h e In t er n et . T h e d a t a p r ov id er s a r e Un ix sy st em s r u n n in g on H P u n d er H P UX a n d on SUN r u n n in g Sola r is. T h e ot h er m a ch in es a r e P Cs u n d er Win d ow s N T.

Steps to implement REMSSBOT

At t h e m om en t t h r ee d em on st r a t or s a r e op er -a t ion -a l. It is t h e in t en t ion t h -a t RE M SSBOT w ill b e ext en d ed in t h ese r e gion s w it h n ew Windo ws GUI

SIS/ CDS Clie nts /

Fro nt e nd

Ce ntral Parts

Re gio nal Enviro nme ntal Pro vide rs / Bac k e nd

WWW GUI (Bro ws e r) Ne ts c ape

REMSSBOT HTTP Se rve r

CDS Databas e

Se rve r

REMSSBOT Wave Se rve r/ CDS

CORBA Naming Se rvic e

REDP Inte rfac e

REDP

RE We b Site HTTP Se rve r

CDS data CDS data

As k REDP Addre s s As k REDP

Addre s s

E-s e rvic e E-s e rvic e

R-Produc t R-Produc t

REDP Spe c ific Que ry Re gis te r REDP Addre s s

Figure 1

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9 / 1 [1 9 9 8 ] 2 7 –3 1

d a t a p r ov id er s, bu t it is exp ect ed t h a t RE M SSBOT w ill a lso b e im p lem en t ed in ot h er r e gion s t o solve s im ila r p r oblem s t h er e.

A complete new REM SSBOT environment T h e follow in g s t e p s h ave t o b e t a k en t o im p le-m en t RE M SSBOT in a n ew en v ir on le-m en t . T h is m ea n s s et t in g u p a com p let e s y s t em w h er e on ly t h e d a t a p r ov id er s (d a t a b a ses) exist . T h e a m ou n t of wor k a n d cos t is s t r on gly d e p en d en t on t h e st r u ct u r e of t h e

d a t a b a se of t h e exis t in g d a t a p r ov id er s a n d h ow m u ch t h e n eed ed RE DP in t er fa ce d iffer s fr om t h e a lr ea dy exist in g in t er fa ces. Also t h e n eed ed com m u n ica t ion p lay s a n im p or t a n t r ole in t h e cos t a sp ect .

T h e st e p s t o t a k e for s et t in g u p a n ew RE M SSBOT en v ir on m en t a r e t h e follow in g: 1 An a ly sis p h a se:

• in ven t or y of w ish es;

• w h ich d a t a p r ov id er s a r e d esir ed . 2 Defi n e R-In fo, R-P r od u ct s a n d R-Ser v ices. 3 Defi n e t h e E -ser v ices.

4 RE DP :

• d evelop RE DP in t er fa ces. Ch oos e fr om w h ich exis t in g RE DP bu ild in g block s ca n b e in h er it ed ;

• im p lem en t ea ch E -ser v ice on ea ch RE DP ;

• ch oose a d a t a b a se for t h e look u p d a t a -b a se;

• F ill in t h e look u p d a t a b a se.

5 Ch oose u ser in t er fa ce (WE B or Win d ow s). 6 Ch oose DBMS for CDS d a t a b a se.

7 Set u p t h e com m u n ica t ion s: • CORBA;

• N a m in g Ser ver ; • H TTP Ser ver.

8 Develop u ser a p p lica t ion in t er fa ces. 9 F ill in CDS d a t a b a s e.

Add a new data provider

To a d d on ly a n ext r a d a t a p r ov id er is in gen -er a l a less ext en sive job.

F ir st of a ll, t h e a m ou n t of effor t a n d cost d e p en d s s t r on gly on t h e st r u ct u r e of t h e n ew d a t a p r ov id er in r ela t ion t o t h e exis t in g con -n ect ed d a t a p r ov id er s.

Secon d , t h e effor t a lso d e p en d s on t h e ser -v ices t h a t n eed t o b e im p lem en t ed . If n o ext r a ser v ices n eed t o b e im p lem en t ed , t h a t m ea n s t h a t t h e a lr ea dy exist in g ser v ices a r e su ffi-cien t for t h e n ew d a t a p r ov id er, n o ext r a effor t is n eed ed .

T h ir d , it d e p en d s on t h e n eed ed com m u n i-ca t ion in r ela t ion t o p er for m a n ce r eq u ir e-m en t s a n d a lr ea dy ava ila ble con n ect ion s.

F in a lly, t h e CDS h a s t o b e u p d a t ed for t h e d a t a in t h e n ew d a t a p r ov id er.

Future activities

In t h e fu t u r e a lot of a ct iv it ies st ill h ave t o b e com p let ed . T h e ob ject ives of t h e RE MSSBOT p r oject a r e t o r ea lise t h r ee d em on st r a t or s t o p r ove t h a t t h e sy s t em a r ch it ect u r e r ea lly wor k s. T h e u ser s ca n give t h eir op in ion a n d a n eva lu a t ion p r oces s a ssess es t h e r esu lt s of t h e p r oject . At t h is m om en t it look s ver y su ccessfu l. Bu t t h er e a r e st ill a lot of a ct iv i-t ies i-t h a i-t a r e ou i-t sid e i-t h e scop e of i-t h e p r ojeci-t ,

DZ L

VM M

REPD DONAR DZ L UNIX

CORBA Namings e rve r

Ne ts c ape De s kto p c o mpute r

CDS SIS We b-s e rve r VWave CORBA MS-Windo ws -NT

GIS-applic atio n

Arc / Info UNIX Wo rks tatio n

DDM

REDP DONAR RIKZ

UNIX REDPI

VWo rks CORBA C-c o nne c t DDM MS-Windo ws -NT

RIKZ

REDP VMM SUN Databas e c o py REDPI

VWo rks CORBA MS-Windo ws -NT

LAN RIKZ -Midde lburg

HTTP

LAN DZ L-Midde lburg

Inte rne t

REDP VMM IBM RS 6 0 0 0 /

AIX Databas e

daily bac kup

LAN Aals t

Figure 3

REMSSBOT hardware imple me ntatio n W4 s e le c tio n

Pro duc t

R-Pro duc t R-Info

Co mpo s e d-s e rvic e Single -s e rvic e

Single -s e rvic e Single -s e rvic e

E-s e rvic e

Databas e s pe c ific SQL o r APL-c o mmand

Data s o urc e 2 ... ...n

Figure 2

(5)

9 / 1 [1 9 9 8 ] 2 7 –3 1

t h a t n eed t o b e d on e t o m a k e RE M SSBOT su ccess fu l in t h e lon g t er m .

Activities to improve REM SSBOT

CDS

RE M SSBOT is b a s ed on t h e E TC/ CDS d a t a -m od el ver s ion 1.0 w h ich w a s r elea s ed in N ovem b er 1996. Sin ce t h en s ever a l n ew ver -sion s w er e r elea s ed . In Se p t em b er ver s ion 2.0 w a s r elea s ed . It is n eces s a r y t o a d a p t t h e RE M SSBOT s y s t em t o t h is ver s ion t o t a k e fu ll a dva n t a ge of fu r t h er in it ia t ives of t h e

E TC/ CDS. We n eed t o exa m in e t o wh a t ext en t t h e n ew E TC/ CDS t ools ca n b e h elp fu l.

Als o a m a in t en a n ce t ool h a s t o b e d evelop ed t o m a k e t h e in it ia l s et -u p a n d t h e m a in t e-n a e-n ce of t h e CDS m u ch ea s ier. N ow it t a k es a lot of m a n u a l wor k t o m a in t a in t h e CDS.

Te c hnic al impro ve me nts and mainte nanc e

T h e d em on st r a t or s a r e d evelop ed in a n in cr e-m en t a l p r ocess. T h is h a s e-m a n y a dva n t a ges con s id er in g t h e u s er in p u t , bu t fr om a t ech n ca l p oin t of v iew s om e s olu t ion s a r e n ot op t i-m a l, a n d soi-m e i-m u st b e ch a n ged t o avoid fu t u r e p r oblem s or t o m a k e p os sible ext en -sion s fea s ible.

On t h e p oin t of s ecu r it y, by u s in g t h e In t er -n et s om e im p r ovem e-n t s h ave t o b e m a d e.

Als o t h e m a in t en a n ce of RE M SSBOT h a s t o b e or ga n is ed . Beca u se RE M SSBOT is a t oolk it t h a t is m ea n t t o b e ext en d ed a n d

a d a p t ed , t h e s et -u p of ver sion con t r ol a n d m a in t en a n ce is ver y im p or t a n t . T h is ca n p ossibly b e d on e b est by d efi n in g bu ild in g block s t h a t a r e m a n a ged a n d m a in t a in ed .

Activities related to the extension of REM SSBOT use

Mo re data pro vide rs in the re gio ns

T h e t h r ee d em on st r a t or s w ill b e ext en d ed w it h n ew d a t a p r ov id er s, n ew u ser s, n ew fu n ct ion s a n d con n ect ion s t o n ew a p p lica -t ion s.

Mo re imple me ntatio ns

T h e in t er est in RE MSSBOT is r a t h er h igh . Sever a l or ga n isa t ion s a r e con sid er in g a p p ly -in g RE MSSBOT -in t h eir s y st em a s a t ool t o a ccess d a t a .

Directory UMM :Data Elmu:jurnal:E:Environmental Management and Health:Vol09.Issue1.1998:

REMSSBOT technical implementation

M aarten Galle

Introduction

Functionality of REMSSBOT

Technical choices

REMSSBOT system architcture

REMSSBOT services

Hardware implementation

Steps to implement REMSSBOT

Future activities

Further reading