1. Dave Catherman BSEE /CS 1979 U. of Idaho 9 years in U.S. Navy
Helicopter Pilot
Computer Systems Manager
4 years at Honeywell Inc.
Quality Engineer
Application Developer
4.5 years at JAARS
Technology Evaluator
Database Application Design
4/12/2019

2. JAARS Technical Support for Wycliffe Bible Translators
Aviation Support
Telecommunications
Construction and Maintenance
Purchasing and Shipping
Material Transportation
Computing
4/12/2019

3. International Computers Services (ICS) provides services in:
Buying computers and software
Training on how to use the PC
Software development
Access to linguistics applications
Repair and maintenance
User support services
Networking and
Adapting the latest technology
4/12/2019

4. Systems Engineering Department
Technology Evaluator
Evaluate new technology - write reports
God can use technology to speed evangelization
Database Application Development
International database coordinator
Design/develop database applications for field
Teach Microsoft Access classes
4/12/2019

5. Harnessing Distributed Database Technology
Overview:
The Problem
Possible Solutions
Our Situation
4/12/2019

6. The Problem: Collecting the Information
Data is located in the field offices
No on-line communication
Require reports to be submitted
Re-key the reports into system
Fields have no automated systems standard
Each administration develops own system
No standard way to submit electronically
4/12/2019

7. The Problem: Distributing the Information
Decision makers are in the field
Projects depend on analysis of the data
Personnel need advanced notification
No on-line means of querying data
Most field sites don’t have Internet yet
Printed reports lack flexibility
CD-ROM distribution too slow
4/12/2019

8. The Solution: Distributed Databases/Replication
Duplicate copy of database in each location
Updates are replicated to and from each copy
Usually requires a network connection
Available now in most database servers
Oracle/Sybase/Informix/SQL Server
Most fields don’t have server capability
Most fields don’t have Internet connection
4/12/2019

9. The Recommendation: Microsoft Access 97
PC based database (on Windows 95/NT)
Fully relational development environment
Good Rapid Application Development
Supports direct and indirect replication
Has partial replication capability
Replication is record based
4/12/2019

10. The Goal: Partial Replication - User Security
Master database located at home office
Partial replication for each field site
feature of MS Access 97
User/group level security for each user
Restricted views for general querying
Encrypted links for sensitive locations
Code names used for sensitive projects
4/12/2019

11. The Strategy: Indirect Replication over E-mail
Indirect synchronization
Can be scheduled or on demand
Places updates file in a dropbox directory
Use as transport mechanism
MAPI process to attach file to a message
Normal delivery to destination
MAPI process to detach file in dropbox
Updates picked up by Synchronizer
4/12/2019

12. Issues and Problems: Upgrading PCs to support Windows 95
Program control of the updates and dropbox
Personnel for conflict resolution
Conflict results from two sites updating the same record
Process or person must resolve conflict
Size of database and update files
4/12/2019

13. Other Possible Solutions:
Wait until all fields have Internet
Write our own replication system
Continue to look for other vendor solutions
4/12/2019

14. Questions and Comments
4/12/2019