Client/Server Computing

Ajay Kumar Shrivastava

Network Operating System (NOS)

• It manages the services of the server• It exists at the session and presentation layers

of the client machine’s network management s/w.

• It provides the links to upper layer network management s/w.

• It offers reliability, performance, security, and internetworking.

Most popular LAN OS

• NetWare from Novell• LAN Manager from Microsoft• OS/2 LAN Server from IBM• VINES from Banyan

NetWare

• NetWare Lite is the new member of the family.• It is DOS based NOS.• Designed for small offices and peer-to-peer

systems.• NetWare can be used with bus or Token ring.• It can integrate DOS, OS/2, Macintosh, and UNIX

clients on a network.• NetWare 3.11 supports TCP/IP and its native

IPX/SPX protocol.

LAN Manager

• It works across multiple protocols, supporting NetBIOS or TCP/IP.

• It supports the mainframe environment through its compatibility with IBM OS/2 LAN server.

• It offers interoperability with NetWare through its NetWare connectivity program.

• It requires that the server run on OS/2.

LAN Manager Features

• Concept of a domain• OS/2 named pipes facility• Support for multiprocessing• A preemptive scheduler• Remote access service

OS/2 LAN Manager

• IBM has added two enhancements-Aliases-Dynamic resource sharing

• It facilitate the administration of large networks.

VIrtual NEtworking System (VINES)

• It is designed for large networks.• It can run over LANs server-to-server

interconnections to provide a single, global view of the enterprise network.

• It is based on a UNIX kernel.• VINES server can be a 286-486 machine running a

POSIX – complaint version of UNIX System V.• VINES internet protocol (VIP) is a native protocol.

Training

Training advantages of GUI applications

• Reduced training cost-Training cost by 30%-40%- Training Time 10 weeks to 4 weeks

• Training the technical staff- Reduce the downtime- Overcome the Culture shock

System administrator training

• Should understand the requirement of System availability

• Ease of user• Should ware of technical and human

interaction protocols of working remotely.

System administrator training

• LAN administration• WAN administration• OS issues• PC/Workstation issues• Application issues

Programmers resistance to new technology

Database administrator training

END user training

• Workstation operations• Application and new technologies

Training delivery technology

C/S System Development Methodology

• It describes a disciplined process through which technology can be applied to achieve the business objectives.

• It describes the process through the entire life cycle.

• Most integrator groups have their own life cycle management methodology.

System Planning

• Initiate system planning• Gather data• Identify current situation• Describe existing situation• Define requirements• Analyze applications and data architectures• Analyze technology platforms • Prepare implementation plan

Project Initiation

• Screen request• Identify relationship to long range• System plan• Initiate project• Prepare plan for next phase

Architecture Definition

• Gather data• Expand the requirements to the next level of

detail• Conceptualize alternative solutions• Develop proposed conceptual architecture• Select specific products and vendors

Analysis

• Gather Data• Develop a logical model of the new

application system• Define general information system

requirements• Prepare external system design

Design

• Perform preliminary design• Perform detailed design• Design system test• Design user aids• Design conversion system

Development

• Set up development environment• Code modules• Develop user aids• Conduct system test

Facilities Engineering

• Gather data• Conduct site survey• Document facility requirements• Design data center• Plan site preparation• Prepare site• Plan hardware installation• Install and test hardware

Implementation

• Develop contingency procedures• Develop maintenance and release procedures• Train system users• Ensure that production environment is ready• Convert existing data• Install application system• Support acceptance test• Provide warranty support

Post-implementation Support

• Initiate support and maintenance services• Support hardware and communication

configuration• Support software• Perform other project completion tasks as

appropriate

System integration life cycle1

System planning

2Project

initiation

3Architect-

ure Definition

4

Analysis

5

Design

6Develop-

ment

7Facilities Engineeri

-ng

8Impleme-

ntation

9Post

implementation

support

System Encyclo.