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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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