Introduction

With the evolution of wireless technologies that continue to offer higher data rates using both licensed and unlicensed spectrum, the number of portable, handheld computing devices using wireless connectivity to the Internet has increased dramatically. Another major category for growth in wireless devices is that of embedded wireless devices or sensors that help monitor and control objects and events in the physical world via the Internet. Vehicular networking is an emerging application for wireless networking with a focus on increased road safety.

The broad architectural challenge facing the wireless and network research communities is that of evolving the Internet architecture to efficiently incorporate emerging wired and wireless network elements such as mobile terminals, ad hoc routers, and embedded sensors and to provide end-to-end service abstractions that facilitate application development. A top-down approach to the problem starts by identifying canonical wireless scenarios that cover a broad range of environments such as cellular data services, WiFi hot spots, mobile peer-to-peer (P2P), ad hoc mesh networks for broadband access, vehicular networks, sensor networks, and pervasive systems. These wireless application scenarios lead to a rich diversity of networking requirements for the future Internet that need to be analyzed and validated experimentally. One of the key challenges faced in characterization and evaluation of these complex wireless scenarios is the lack of generally available tools for modeling, emulation, or rapid prototyping of a complete wireless network.