Liu, Mingyan D.Karir, ManishRaissi-Dehkordi, MajidBaras, John S.Internet technology as a widely accepted modern telecommunicationstandard has been widely extended to combine with numerous othertechnologies, e.g., satellite, ATM, wireless. This is whatwe term Hybrid Internet. Along with this technology emerging,various enhancements and alterations of standard TCP/IP for differentpurposes have been proposed and studied intensively. More and morefrequently we are facing the question of how to choose from thesedifferent schemes to design a system for a particular purpose, whichwould inevitably involve the interaction and trade-off study. We believethat simulation is a powerful tool for this type of work.In this paper, we describeour implementation of a Hybrid Internet testbed which includesa series of traffic models and TCP/IP enhancements.The goal of our work is to makea set of reusable modules upon which we can build complex systemsto study the standard protocols and their variations.We also present application examples using these module components.en-USInternet technologyTCP/IPsimulationTCP splitting/spoofingscheduling and buffer management,Technical Report