Communications and Networking Technologies: Guest Editors’ Introduction

86 world in technology development. From the perspective of communications and networking technologies, as well as associated algorithms, protocols, and controls, APL’s efforts include providing the following: • Maximum wireless communication capability out of limited spectrum, especially in challenging communication environments, including intermittent and unpredictable link availability because of terrain, obstacles, weather, jamming, etc.; large delays in satellite-based communication and very large delays in interplanetary communication; and underwater acoustic communication • Reliable communication among highly mobile users with minimal infrastructure support • Very high data rates without the benefit of fixed optical infrastructure (e.g., between airborne platforms and between an airborne platform and a ground station) For several decades, researchers at APL have developed and applied expertise in communications technologies for the benefit of their government sponsors. Early focus was on satellite communication (SATCOM) and end-to-end network solutions for specialized combat systems. However, as wireless and optical communication and Internet Protocol (IP)-based networking stormed the commercial world during the last two decades, APL’s sponsors began exploring ways to exploit advances in commercial communication and networking technologies to multiply force effectiveness. The concepts of network-centric warfare and the Global Information Grid were born. APL initiated a broad-based effort to help its sponsors address critical challenges in realizing the vision created by these concepts. Special focus has been on sponsors’ needs that were not addressed adequately by the commercial technologies and on situations in which APL’s sponsors must lead the commercial Communications and Networking Technologies: Guest Editors’ Introduction