What This Document Is
This tutorial provides a foundational overview of NS, a widely-used network simulator. Originally developed as REAL and evolving through NS and NS-2, this resource delves into the core principles and practical applications of discrete event simulation within the context of computer networking research and education. It’s geared towards students and researchers seeking to model and analyze network behaviors. The material appears to be from a Computer Networks course (CSci551) at the University of Houston-Clear Lake, dating back to Spring 2002, but the concepts remain highly relevant.
Why This Document Matters
This tutorial is invaluable for anyone involved in network protocol design, performance evaluation, or traffic analysis. It’s particularly useful for students learning about network simulation for the first time, or those needing a refresher on the NS environment. Researchers can leverage this understanding to build and test new networking concepts in a controlled, virtual setting. If you're looking to gain a deeper understanding of how network protocols function and interact, and how to model them effectively, this resource will be a strong starting point.
Topics Covered
* The fundamental concepts of discrete event simulation.
* The history and evolution of the NS network simulator.
* The core components of the NS simulation environment, including NS itself and the Network Animator (NAM).
* Traffic modeling and application layers within NS.
* Transport and routing protocols supported by NS.
* The software structure of NS, including its object-oriented design and the interplay between C++ and OTcl.
* An overview of key simulation scenarios, such as web traffic, TCP behavior, and queuing systems.
What This Document Provides
* A historical context for the development of NS.
* An explanation of the simulator’s goals and its role in networking research.
* A breakdown of the key objects and their functions within the NS framework.
* Insights into the advantages and trade-offs of using both C++ and OTcl in NS simulations.
* An outline of essential concepts and case studies to guide your learning.
* A foundation for building and analyzing network simulations using NS.
