DESIGN AND MANAGEMENT OF COMPUTER NETWORKS

Presented By

CSK

@ oxford

engineering college - Trichy

APPLICATIONREQUIREMENTS

Types of requirement analysis

User

Application

Device

Network

Other

Application Requirements

Application requirements are requirementsthat are determined from applicationinformation, experience, or testing, andrepresent what is needed by applications.

Application requirements are more technicalthan user requirements but may still besubjective.

Application requirement

network applications based on human factors and technology attributes.

The first term, human factors, addresses human perception of different kinds of media, such as conventional text, audio and video.

The second term, technology attributes, represents the different technological aspects of these network applications, such as data processing applications, web applications, system applications(CPU, Memory(storage)) .

Example Application requirement

Application requests (for example, web page requests)

Database transactions (for example, data queries or updates)

Messaging protocols (for example, putting a message on the queue)

Authentication service (for example, encryption, decryption, login purpose)

API calls (for example, restful interface calls)

Application system

Application system

Tier 1: Web server: used to distribute requests toone or more application servers. This web serverhas load balancing capabilities and constitutesthe web tier.

Tier 2: Application server: used to host the e-commerce application. These servers constitutethe application tier.

Tier 3:Database server: used to store theapplication's data. This server resides at thedatabase tier

Types of application requirements

Application Types

› Based on service and performance requirements,applications were type as:

mission-critical RMArate-critical CAPACITY, orreal-time/interactive DELAY

These application types are described by theirrequirements and service metrics.

Application Types

A loss of any part of RMA in such applicationsmay be serious or disastrous, such as:

› Loss of revenue/profit or customers.› Un-recoverable information or situation.› Loss of sensitive data.› Loss of life / business .

In terms of capacity, there are some applicationsthat require a predictable/guessable, bounded/limited, or high degree of capacity include voiceand non-buffered video.

Application Types

Delay: It can take a long time for a packet tobe delivered across the networks.

From an application service perspective,

optimizing the total,

end-to-end(source to destination), or

round-trip(cycle) delay is usually the mostimportant things.

Applications Groups

It is often useful to group applications with similar performance characteristics.(nokia, samsung,micromax)

Application can be identified using the requirements analysis process.

› Telemetry Applications(wireless : radio, ultrasonic, or infrared, blue-

tooth systems)› Visualization Applications: computer graphics.: 2D,3D

› Distributed Applications: software that is executed or run on multiple computers within a network.(middleware / SOA platform)

› Web, Access and Use Applications(php/ mysql)› Operations(Logical / arithmetic), Administration and

Maintenance.

Application Locations

to determine where application applies in an environment.

This will help in mapping traffic flows during the flow analysis process.

Application types, their performance requirements, their locations, and application groups form the interface between the application component and the rest of the system.

Device : piece of equipment that has been made for some special purpose.

Device Requirements

Device Requirements

Device Type

Devices can be grouped into three categories:

generic computing devices: (laptop , mobile phone),their requirements are important from an end-to-endperspective,

they provide the interface between applications andthe network.

Servers(windows/unix ): have an impact on the trafficflows within the system.

specialized devices(wireless) : (blue-tooth/IR/ blue tooth headset) are devices that provide specific functions to their users.

Performance Characteristics

For many environments, it may be difficult todetermine or measure the performancecharacteristics of its devices.

Note that device problems frequently aremisinterpreted as network problems.

Understanding at the device component level canhelp you recognize such bottlenecks/problemsearly in the analysis process.

Device Locations

Location information helps to determine the relationships among components of the system.

Location information also helps to determine the traffic flow characteristics for the system.

The interface between the device component and the rest of the system consists of the types of devices, their location dependencies, and their performance characteristics.

Network requirements

Network : interconnected systems.

Components of a computer network:

Hosts : (PCs, laptops, handhelds)

routers & switches : (IP router, Ethernet switch)

links : (wired, wireless)

Protocols : (IP, TCP, CSMA/CD, CSMA/CA)

Applications: (network services)

humans and service agents

Network Requirements

Existing & Migration / populate

Most network architectures/designs today need to incorporate existing networks.

This includes

system upgrades,

migrating (move from one part of something to another part)to a new or different technology or

protocol, or upgrading network infrastructure.

Existing & Migration / populate

Sometimes the network architecture and designmust accommodate any dependencies andconstraints imposed by the existing network.

Examples include the following:

Scaling dependencies. How will new networkchange the size and scope of the system? or willthe change be within the LAN/MAN/WANboundaries of the existing network?

Location dependencies .

Based on the two – ways

Performance constraints:

Performance constraints:

Location dependencies

Performance constraints:

Existing network performance characteristics should be integrated into the performance requirements of the planned network.

Network, system, and support service dependencies.

Features :

includes network addressing strategies, security, choices and configurations of routing protocols, and naming strategies.

Location dependencies

Interoperability dependencies:

The boundaries between existing and plannednetworks are points where service informationand performance guarantees need to betranslated.

Network obsolescence/ old model. Wheneverpossible, it should be noted that parts of thenetwork will need to be transitioned out of theplanned network.

Network Management & Security

There are four categories of networkmanagement tasks:

Monitoring for event notification

Monitoring for metrics and planning

Network configuration

Troubleshooting

List of some potential network management requirements:

Monitoring methods

Instrumentation methods.

These include the network management protocols (SNMPv3, CMIP, RMON), parameter lists (MIBs), monitoring tools, and access methods.

Sets of characteristics for monitoring.

Centralized versus distributed monitoring.

Performance requirements.

List of some potential(risk) network management requirements:

it is also need to be determined a security risks by performing a risk analysis for both the existing network and planned network.

Security requirements and the results of the risk analysis are used to develop a security plan and define security policies for the network.

THANK YOU