Solution for Large Client/server Software Updating Problem

Yuanming Zhang

October 12, 2000

Outline

• Subject of the problem-background knowledge• Problem Statement• Goal• analyses• Solution• Test method• Conclusion

Subject of the Problem

Interested in:

large client/server environments

specifically in updating client applications

Large Client Server Environment

Structure: Wan network

Clients : many

Database : Huge

OS: most clients use Unix

Examples of Large Client/Server Environments

Banking (Citibank)

Travel (Greyhound)

Transportation (U.P.S or Federal Express)

Multiple shop/super market (Circuit City, Walmart)

Some Government departments (driver’s license)

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What kinds of services are preformed in client applications?

• Thin Client: User interface, data I/O, data communication with

server

• Fat Client: All of above and Database

About the Use of Thin Clients

Most companies tend to choose thin clients because:• In fat client/server mode, the remote client

cannot easily access the local database;• The database in fat client/server needs more

maintenance;• Thin client/server mode does not have above

problems

Problem Statement• Future: Software should be updated according to

the business requirement time frame.• Presently:

– It’s difficult to develop or modify a user interface application in Unix, especially a menu.

– Install/reinstall time consuming– Addition burden on customer training and retraining

Goal

Devise a Solution to Resolve the Difficulty in Updating/creating the

Client Application.

I Am Going to Find/define a New Kind of Client to Solve the

Problem.

Literature Review

• Wyse produces winterm which is a kind of terminal built in Windows NT OS

It’s neither a good solution nor a successful seller

It do have good interface but it do not have good stabilization due to the OS

Steps Already Taken in Defining a New Type of Client:

• analyzed the operating systems of clients

• analyzed a current large client/server

• choose the best operating system with the minimum number of weak points and enhance it to extend its capability with updating client server applications

Comparison Between Unix and Windows :FFeeaattuurree UUnniixx WWiinnddoowwss 9955//9988////NNTT

Security High Low

Stability High Low

User Interface development Difficult Easy

Development Tool Few Many

Efficiency High Low

Management Easy Difficult

Training Difficult Easy

PDA (Personal Digital Assistant)Palm OS and Windows CE

The PDA come installed with palm OS more than with windows CE.

The PDA is designed as PDA not PC. PDA does not have keyboard and mouse…

We should cut the prejudge mind.

Can We Use Windows Application in Client?

No.

Because:

need time

need stability

need safety

Solution:

Build a special browser as client software.

Download the server html file to build nice user interface

Thousands of Html edit tools can be used

Advantage of the New Browser

Never waste time to reinstall software for client;

The user interface which based on html file is easy to make and maintain

The changing requirement of the application still can not be avoided, but we will never have to worry about the client menu. We save in the effort of designing interfaces.

What Kind of Browser We Can Use?

Depends on application.

Most Big C-S need not use mouse, scroll bar;

But they do have dialog box, list box and menu

Which OS Should Be Used for This Browser?

We have several choices:

• 1 Still in Unix

• 2 Terminal with Build in Browser

• 3 New kind of OS

Which Html Version Should We Use?

We need not only use Html, we can design the special file format for the special purpose.

But we should make it the standard protocol.

Terminal OS

We can also build OS and browser into a terminal and link the terminal to the server. Then change the C-S structure into T-S structure.

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Design Terminal OS

The design way of the terminal OS should like the way of design Palm OS: think of application, user, input, output; think of java technology

And we should also build in encryption software.

Test Fields and Variables:

1 Application development time:

programmer number * year

2 Application reinstall time:

client number * second

3 Application operating:

CPU occupancy: Speed*occupancy rate

RAM occupancy: MB

Network occupancy: Byte per transaction

Conclusion

• Html and browser can not only be used in the Internet, it can also help us to build the client interface in a big C-S system.

• Hope the future’s e-business can also benefited from these.