Copyright 2002: LIIF Technology Architecture Review Database Application Architecture Database Application Architecture Collaborative Workgroup Architecture

Copyright 2002: LIIF

Technology Architecture ReviewTechnology Architecture Review

Database Application ArchitectureDatabase Application ArchitectureCollaborative Workgroup ArchitectureCollaborative Workgroup Architecture

The following document is posted by the Low Income Investment Fund (LIIF) in accordance with the requirements of the Fannie Mae Foundation’s October 2001 grant in support of LIIF’s continued information technology (IT) development. Materials posted by LIIF outline the organization’s strategic IT plan, as well as document the implementation process of this plan. LIIF’s IT plan included customization of loan servicing software, report automation, impact statistics generation, fund administration, and asset liability monitoring. LIIF’s knowledge and experience developing this IT workplan is posted as an aid to other non-profit Community Development Financial Institutions (CDFIs) who may be generating their own IT workplan and who may find the subsequent materials helpful in that regard.





Database Application ArchitectureDatabase Application Architecture


Desktop DatabaseDesktop Database Client-Server DatabaseClient-Server Database Replicating DatabaseReplicating Database Terminal Server (Thin Client)Terminal Server (Thin Client) Web Application (Thin Client)Web Application (Thin Client) Extending a Desktop Database Application Extending a Desktop Database Application

across a WANacross a WAN






Desktop Database Architecture

DatabaseApplication

DatabaseFile

User PC

NetworkFile Server



DatabaseApplication

DatabaseFile

User PC

NetworkFile ServerSelect Loan record

Where Loan Number = 123



DatabaseApplication

DatabaseFile

User PC



Loan Table



DatabaseApplication

DatabaseFile

User PC



Loan Table

Final selection of Loan recordFrom loan tableOccurs in client databaseApplication.



Reasonably efficient on single PCReasonably efficient on single PCBarely adequate on a LANBarely adequate on a LANUnacceptable for a WANUnacceptable for a WAN

Desktop Database ArchitectureDesktop Database Architecture



Unacceptable query response times across Unacceptable query response times across WAN:WAN:

Transfer Time for 6 Mb Table:Transfer Time for 6 Mb Table:3.6 minutes at 384 kbps3.6 minutes at 384 kbps10.8 minutes at 128 kbps10.8 minutes at 128 kbps47.7 minutes at 28.8 kbps47.7 minutes at 28.8 kbps

Desktop Database ArchitectureDesktop Database Architecture












Client-Server Database Architecture

DatabaseFile

NetworkDatabase Server

DatabaseServer

ClientApplication

User PC



DatabaseFile


DatabaseServer

ClientApplication

User PC

Select Loan recordWhere Loan Number = 123

Query sent to Database Server



DatabaseFile


DatabaseServer

ClientApplication

User PC


Selection of Loan recordFrom loan tableoccurs in Database Server.




DatabaseFile


DatabaseServer

ClientApplication

User PC




Database Sever returns 1 Loan record



DatabaseFile


DatabaseServer

ClientApplication

User PC




Database Sever returns 1 Loan record

Client applicationDisplays Loan record 123



AdvantagesAdvantagesVery Efficient across WANVery Efficient across WAN

28.8 kbps28.8 kbps 1-10 active users1-10 active users

128 kbps128 kbps 10-500 active users 10-500 active users

Client-Server Database ArchitectureClient-Server Database Architecture



AdvantagesAdvantagesVery Efficient across WANVery Efficient across WAN

28.8 kbps28.8 kbps 1-10 active users1-10 active users

128 kbps128 kbps 10-500 active users 10-500 active users

DisadvantagesDisadvantagesRequires installing client application on Requires installing client application on

every user workstationevery user workstationUnusable if WAN is down Unusable if WAN is down

Client-Server Database ArchitectureClient-Server Database Architecture












Replicating Database ArchitectureReplicating Database Architecture

LIHF Home OfficeLIHF Home Office

LIHF Branch OfficeLIHF Branch Office

Replication Server(s)

ReplicatedData

WAN

ReplicatedData

Replication Server(s)

Replication Server(s) are responsible for coordinating all user changes to data:





AdvantagesAdvantages Users experience fast response times because Users experience fast response times because

replicated databases are local databasesreplicated databases are local databases Replication database tolerate slow and Replication database tolerate slow and

intermittent WANsintermittent WANs




AdvantagesAdvantages Users experience fast response times because Users experience fast response times because

replicated databases are local databasesreplicated databases are local databases Replication database tolerate slow and Replication database tolerate slow and

intermittent WANsintermittent WANs

DisadvantagesDisadvantages Replication servers must be installed in each Replication servers must be installed in each

branch office.branch office. Inevitable data concurrency problems must be Inevitable data concurrency problems must be

manually reconciledmanually reconciled




Typical Replication Server Based Applications:Typical Replication Server Based Applications: Network Security (Domain Server)Network Security (Domain Server) Email & Collaborative WorkgroupEmail & Collaborative Workgroup Geographically Distributed Custom DatabaseGeographically Distributed Custom Database











Terminal Server ArchitectureTerminal Server Architecture

(Traditional Windows Architecture)

Mouse MoveMessages

KeyboardCharacterMessages

Screen PaintInstructions

Windows Application

User PC Copyright 2002: LIIF

Mouse MoveMessages

KeyboardCharacterMessages

Terminal ServerFor Each User:• Windows Application• ‘Screen Scraper’ Interpreter

User PC

Client ScreenPainter

Network Traffic for each User:• Mouse Move Messages• Keyboard Character Messages• Screen Paint Instructions

Screen PaintInstructions




AdvantagesAdvantages– No installation of application software on client No installation of application software on client

PCPC




AdvantagesAdvantages– No installation of application software on client No installation of application software on client

PCPC

DisadvantagesDisadvantages– Requires very large servers and fast networksRequires very large servers and fast networks– Many windows applications do not perform well Many windows applications do not perform well

in terminal server environmentin terminal server environment– New, untested technologyNew, untested technology








Web Application ArchitectureWeb Application Architecture

Web Application:Web Application:• Accesses and updates data in a database Accesses and updates data in a database

( More than a static Web site.)( More than a static Web site.)• Contains application programming logic in Web ServerContains application programming logic in Web Server

WebApplication

DatabaseFile

User PCWith Web Browser Database Server

DatabaseServer

Web Server

Internet



AdvantagesAdvantages Allows application access from any locationAllows application access from any location Standard, ubiquitous browser interfaceStandard, ubiquitous browser interface Particularly suited for external usersParticularly suited for external users




AdvantagesAdvantages Allows application access from any locationAllows application access from any location Standard, ubiquitous browser interfaceStandard, ubiquitous browser interface Particularly suited for external usersParticularly suited for external users

DisadvantagesDisadvantages Requires instensive use of Web server resourcesRequires instensive use of Web server resources Inferior user interface (compared to Windows)Inferior user interface (compared to Windows)




New Loan Servicing Packages (re)written New Loan Servicing Packages (re)written using Web Application Architecture:using Web Application Architecture:













Extending a Desktop Database Extending a Desktop Database Application across a WANApplication across a WAN

Run the application in a Terminal Server Run the application in a Terminal Server environment.environment.

Create a Web Application ‘front end’.Create a Web Application ‘front end’.


Extending a Desktop Database Extending a Desktop Database Application across a WANApplication across a WAN

Run the application in a Terminal Server Run the application in a Terminal Server environment.environment.

Create a Web Application ‘front end’.Create a Web Application ‘front end’. If the branch offices only need read If the branch offices only need read

access:access:– Copy the database across the WAN.Copy the database across the WAN.– Create reports and distribute them via e-mail.Create reports and distribute them via e-mail.









Makes it easy for teams to: Makes it easy for teams to:


Collaborative Workgroup ArchitectureCollaborative Workgroup Architecture


Makes it easy for teams to: Makes it easy for teams to: – Share informationShare information




Makes it easy for teams to: Makes it easy for teams to: – Share informationShare information– Work together on projectsWork together on projects




Makes it easy for teams to: Makes it easy for teams to: – Share informationShare information– Work together on projectsWork together on projects– Assign task responsibilitiesAssign task responsibilities




Makes it easy for teams to: Makes it easy for teams to: – Share informationShare information– Work together on projectsWork together on projects– Assign task responsibilitiesAssign task responsibilities– Establish task deadlinesEstablish task deadlines




Makes it easy for teams to: Makes it easy for teams to: – Share informationShare information– Work together on projectsWork together on projects– Assign task responsibilitiesAssign task responsibilities– Establish task deadlinesEstablish task deadlines– Track task statusTrack task status




Makes it easy for teams to: Makes it easy for teams to: – Share informationShare information– Work together on projectsWork together on projects– Assign task responsibilitiesAssign task responsibilities– Establish task deadlinesEstablish task deadlines– Track task statusTrack task status– Show team members their work pending Show team members their work pending

by priority and deadlineby priority and deadline




Sequence tasks in a complex workflow: Sequence tasks in a complex workflow:




Sequence tasks in a complex workflow: Sequence tasks in a complex workflow: – Control workflow with business rulesControl workflow with business rules

(Business rules can be based on the results of the previous (Business rules can be based on the results of the previous step)step)






– Generate ticklers and reminders of work to be Generate ticklers and reminders of work to be donedone







– Generate alarms when work is not doneGenerate alarms when work is not done







– Generate alarms when work is not doneGenerate alarms when work is not done– Track and analyze historical performance for Track and analyze historical performance for

each workfloweach workflow




Calendars and Scheduling Calendars and Scheduling




Calendars and Scheduling Calendars and Scheduling Tasks and Contacts Tasks and Contacts




Calendars and Scheduling Calendars and Scheduling Tasks and Contacts Tasks and Contacts Document ManagementDocument Management




Calendars and Scheduling Calendars and Scheduling Tasks and Contacts Tasks and Contacts Document ManagementDocument Management Workflow automationWorkflow automation




Calendars and Scheduling Calendars and Scheduling Tasks and Contacts Tasks and Contacts Document ManagementDocument Management Workflow automationWorkflow automation Ticklers, reminders and alarmsTicklers, reminders and alarms




Calendars and Scheduling Calendars and Scheduling Tasks and Contacts Tasks and Contacts Document ManagementDocument Management Workflow automationWorkflow automation Ticklers, reminders and alarmsTicklers, reminders and alarms Configurable views and formsConfigurable views and forms




OS & Foundation Technologies

E-mail Messaging Services

Configuration & Scripting

Collaborative WorkgroupServices








Runs on top of E-mail Messaging ServicesRuns on top of E-mail Messaging Services








Runs on top of E-mail Messaging ServicesRuns on top of E-mail Messaging Services Applications developed using configurationApplications developed using configuration and VB ‘scripting’ and VB ‘scripting’







Lotus Notes / Lotus Domino ServerLotus Notes / Lotus Domino Server




Lotus Notes / Lotus Domino ServerLotus Notes / Lotus Domino Server MS Outlook / Exchange ServerMS Outlook / Exchange Server





– Standard Component Object ModelStandard Component Object Model– Same Script language as MS Office 2000Same Script language as MS Office 2000





– Standard Component Object ModelStandard Component Object Model– Same Script language as MS Office 2000Same Script language as MS Office 2000– 80 ++ Collaboration & Workflow Addons 80 ++ Collaboration & Workflow Addons

utilities built by third parities utilities built by third parities





– Standard Component Object ModelStandard Component Object Model– Same Script language as MS Office 2000Same Script language as MS Office 2000– 80 ++ Collaboration & Workflow Addons 80 ++ Collaboration & Workflow Addons

utilities built by third parities utilities built by third parities – Examples:Examples:

• Keyflow Keyflow ®® Keyfile Keyfile • WorkFolder WorkFolder ®® Eastman Software Eastman Software



Documents

Copyright 2002: LIIF Technology Architecture Review Database Application Architecture Database Application Architecture Collaborative Workgroup Architecture