User Manual

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Chapter 1
Introduction
1.1 A word on traffic generators
Traditionally, routers have been tested using commercial traffic generators, while performance typically has been measured using
packets per second (PPS) metrics. As router functionality and services have become more complex, stateful traffic generators
have become necessary to provide more realistic traffic scenarios.
Advantages of realistic traffic generators:
• Accurate performance metrics.
• Discovering bottlenecks in realistic traffic scenarios.
1.1.1 Current Challenges:
• Cost: Commercial stateful traffic generators are very expensive.
• Scale: Bandwidth does not scale up well with feature complexity.
• Standardization: Lack of standardization of traffic patterns and methodologies.
• Flexibility: Commercial tools are not sufficiently agile when flexibility and customization are needed.
1.1.2 Implications
• High capital expenditure (capex) spent by different teams.
• Testing in low scale and extrapolation became a common practice. This is non-ideal and fails to indicate bottlenecks that
appear in real-world scenarios.
• Teams use different benchmark methodologies, so results are not standardized.
• Delays in development and testing due to dependence on testing tool features.
• Resource and effort investment in developing different ad hoc tools and test methodologies.