Active, programmable, and mobile code networking

As Guest Editors for this Feature Topic on Active, Programmable, and Mobile Networks, we faced a daunting task. Our readers are entitled to the best information from the frontiers of research, and our submitting authors certainly provided a spectrum of such work. As editors, our task was most challenging, since the IEEE editorial staff advised us that, due to prior page commitments, there would be room for only six of our selected articles. While this way difficult news for us, we were most concerned about or submitting authors, leading researchers and practitioners in the field. Many worthy papers were submitted; however, we were unable to bring all the best papers to this publication. Rather, we had to choose among the best, the gems from the gems, and for this we apologize to our readership and our outstanding contributors, some of whom are represented here.