Network Development Life Cycle

The NDLC depends on previously completed development processes such as strategic business planning, applications development life cycle, and data distribution analysis.

If an implemented network is to effectively deliver the information systems that will fulfill strategic business goals, then a top-down approach must be taken.

Top-Down Model and NDLC

Information Systems Development

Systems Development and Network Analysis

Network analysis and design is one step in an overall comprehensive information systems development

process.

Network Designs

Physical network designs involve the arrangement and interconnection of the

physical network circuits and devices,

whereas

Logical network designs involve configuration and definition of services that

will run over that physical network such as

addressing schemes, routing schemes,

traffic prioritization, security, and

management.

Network Development Life Cycle

The word cycle is a key descriptive term of the network development life cycle as it

clearly illustrates the continuous nature of

network development.

Network Analysis and Design Method

The network analysis and design methodology

should be looked upon

as an overall guideline to

the network

development process

rather than a step-by-

step cookbook-style set

of instructions.

Network Analysis and Design Method

is consistent with previous information systems development models.

business, application, and data requirements definition are prerequisites to network design.

activities from various stages of the method often take place simultaneously.

Strategic Network Design

Network design projects are not undertaken at random or on the whim of any network manager.

Network design projects must be aligned with strategic business initiatives and/or the strategic development of the overall corporate IT infrastructure.

NDLC and Proposal Process

It is often prudent to narrow the field of potential respondents by issuing a request for information (RFI).

In-House Network Analysis

Network Device Analysis

IT Infrastructure Management

The achievement of management expectations depends on properly managed components of the IT infrastructure.

An IT infrastructure is made of a combination of separately managed and monitored elements.

Komunikasi Data danJaringan Komputer :Network Management

Aries KusdaryonoMagister KomputerUniversitas Budi Luhur

H-16

Network Management

Network management is the process of controlling a complex data network to maximize its efficiency and productivity

Network Management define as monitoring, testing, configuring, and troubleshooting network components

H-17

Network Management

Network Management uses hardware, software, and humans

The overall goal of network management is to help with the complexity of a data network and to ensure that data can go across it with maximum efficiency and transparency to the users

H-18

Network Management

The International Organization for Standardization (ISO) Network Management Forum divided network management into five functional areas:

Fault Management

Configuration Management

Security Management

Performance Management

Accounting Management

H-19

Configuration Management

The configuration of certain network devices controls the behavior of the data network

Keeping track of device settings and how they function

Configuration management is the process of finding and setting up (configuring) critical devices

Divided into two subsystems : reconfiguration and documentation

Hardware

Software

User Account

H-20

Fault Management

Is the process of locating problems, or faults, on the data network

Dealing with problems and emergencies in the network (router stops routing, server loses power, etc.)

Divided into two subsystem

Reactive Fault Management

Detecting, Isolating, Correcting, and Recording Faults

Proactive Fault Management

Prevent faults from occurring (lifetime for computer or a part of a component)

H-21

Performance Management

Involves measuring the performance of the network hardware, software, and media

How smoothly is the network running.

Can it handle the workload it currently has.

Examples of measured activities are:

Overall throughput

Percentage utilization

Capacity

Traffic

Error rates

Response time

H-22

Security Management

Is the process of controlling access to information on the data network

Provides a way to monitor access points and records information on a periodic basis

Provides audit trails and sounds alarms for security breaches

H-23

Accounting Management

Involves tracking individuals utilization and grouping of network resources to ensure that users have sufficient resources

Involves granting or removing permission for access to the network

Versions

Two major versions SNMPv1, SNMPv2

SNMPv1 is the recommended standard

SNMPv2 has become split into:

SNMPv2u - SNMPv2 with user-based security

SNMPv2* - SNMPv2 with user-based security and additional features

SNMPv2c - SNMPv2 without security

What is SNMP?

SNMP is an application-level tool (protocol) that allows for remote and local management of

items on the network including servers,

workstations, routers, switches and other

managed devices.

Comprised of agents and managers

Agent - process running on each managed node collecting information about the device it is running on.

Manager - process running on a management workstation that requests information about devices on the network.

H-28

SNMP

There are two approaches for the management system to obtain information from SNMP

Traps

Polling

H-29

SNMP Traps

When an event happens on a network device a trap is sent to the network management system

A trap will contain:

Network device name

Time the event happened

Type of event

H-30

SNMP Traps

Resources are required on the network device to generate a trap

When a lot of events occur,the network bandwidth may be tied up with traps

Thresholds can be used to help

Because the network device has a limited view, it is possible the management system has already received the information and the trap is redundant

H-31

SNMP Polling

The network management system periodically queries the network device for information

The advantage is the network management system is in control and knows the big picture

The disadvantage is the amount of delay from when an event occurs to when its noticed

Short interval, network bandwidth is wasted

Long interval, response to events is too slow

H-32

SNMP Traps/Polling

When an event occurs, the network device generates a simple trap

The management system then polls the network device to get the necessary information

The management system also does low frequency polling as a backup to the trap