1. CIS460 – NETWORK ANALYSIS AND DESIGN
CHAPTER 11
Testing Your Network Design

2. Introduction
This chapter covers using industry tests to predict network performance
It also covers building and testing a prototype system and using network-management and modeling tools to anticipate the end-to-end performance and QoS

3. Using Industry Tests Many sources of test results
independent labs
trade journals
vendors
Simple network designs can relay on these tests
Most tests are component tests vice system

4. Building and Testing a Prototype Network System
An initial implementation of a new systems
provides a model on which the final implementation is patterned
validate operation and performance of new system
functional but not full-scale

5. Determining the Scope of a Prototype System
Depends on both technical and non-technical goals
ability to implement depends on resources available
Three ways
As a test network in a lab
Integrated into a production network off-hours
Integrated into a production network normal hours

6. Determining the Scope of a Prototype System (Cont’d)
Remember
warn users in advance
Warn network administrators and other designers - other tests
Warn network managers - alarms/traffic
run multiple short tests
start with small change
monitor test results and discontinue

7. Writing a Test Plan for the Prototype System
Test objectives and acceptance criteria
types of tests that will be run
Network equipment and other resources required
Testing scripts
Timeline and milestones for testing project

8. Developing Test Objectives and Acceptance Criteria
Objectives should be specific and concrete
Response time of application
Throughput of application
Based on business and technical goals
Avoid incorporating biases or preconceived notions
Based on baseline measurement for current system

9. Determining the Types of Tests to Run
Performance - level of service in throughput, delay, delay variation, response time and efficiency
Stress - degradation of service due to increased offered load
Failure analysis - network availability and accuracy, causes of any network outages
Other tests might include manageability, usability, adaptability and security

10. Determining the Types of Tests to Run (Cont’d)
Application response time testing
Throughput testing
Availability testing
Regression testing

11. Documenting the Network Equipment and Other Resources
Test plan should include a network topology drawing and a list of devices that will be required
Other resources including:
lab time
help for co-workers or staff
Help from users
Network addresses and names

12. Writing Test Scripts
Write a script of how the test will be run. Include
Test objectives
Acceptance criterion
Test steps

13. Documenting the Project Timeline
For complex testing projects the test plan should document the project timeline, including start and finish dates for the project and major milestones

14. Implementing the Test Plan
Follow the test scripts
Document your work
Keep a daily activity log

15. Tool for Testing a Network Design
Network-management and monitoring tools - used in a production environment to alert network managers to problems and significant network events.
Modeling and simulation tools - develop modal of network
QoS and service level management tools- analyze end-to end performance for network applications

16. Specific Tools for Testing a Network Design
CiscoWorks Blue Internetwork Performance Monitor
Cisco’s Netsys Tools
Cisco StrataSphere Modeling and Optimization Tools
WANDL’s Network-Planning and Analysis Tools
CACI Products
Make Systems NetMaker XA
NetPredict’s NetPredictor