Towards scalable network emulation

Abstract

The Internet protocol traffic and network emulator (IP-TNE) enables real hosts and a real network to interact with a virtual network. It combines a real-time network simulator with a mechanism to capture packets from and write packets to a real network. Packets generated by external hosts interact with synthetic traffic within the virtual network, providing a controlled environment for testing real Internet applications. IP-TNE can also generate simulated traffic internally enabling its use as a sophisticated workload generator for stress testing real Web servers. This paper focuses on two issues related to the scalability of network emulators, such as IP-TNE. The scalability of the virtual network within the emulator and the scalability of the real-time I/O interface used to interoperate with the physical network. For the scalability of the virtual network, parallel discrete event simulation techniques are employed. The scalability of the real-time interfaces requires handling varying amounts of network I/O and mapping packets into the simulator efficiently.