Network Architecture for Future Wireless Systems
Cellular networks have pervaded many aspects of today's life. Beyond making phone calls and sending text messages, cellular networks provide us with access to the internet from almost anywhere we are, access to emergency assistance from our cars, and wireless access to a growing list of sensors and systems. Cellular networks evolved from the wired phone network -- designed to support voice calls -- but since 2009, cellular networks have carried far more data traffic than voice. Given the trend, are cellular networks designed from the ground-up to support the future of wireless networking, or are these networks fundamentally tied to assumptions from the past? And if the latter, what must change?
Carnegie Mellon University's CROSSMobile project is exploring these questions.
Today's cellular networks bear some similarities to the IP networks we have at home and at work (we use browsers and IP-enabled apps on our client devices to talk, via IP, to cloud services of various sorts), but the network in-between our phones and the cloud is quite different from the network in-between our home PCs and the cloud. Pricing, performance, pervasiveness, provisioning (the way the network is built), and the list of equipment providers differs. These are signs of deeper, more fundamental differences. IP networks grew out of the aim to decentralize network functionality. Cellular networks grew out of the desire to make network performance predictable and controllable -- leading to an almost-inevitable centralization.
We believe that the wide-area wireless networks that will serve the Internet of Things will have characteristics drawn from both types of networks. Like the IP networks of today, innovation will be encouraged via openness. But like more traditional telecommunications networks, performance and predictability will be significantly better. Is this possible?
Software-Defined Mobile Laboratory and Emergency Operations Center
See inside the mobile RF lab supporting CROSSMobile and other CMU-SV research projects
Explorations and Approach
We are actively investigating systems-level challenges that bear on these questions. Our approach combines theory and experimentation. To that end, we have designed and built an on-campus cellular network as a testbed, with virtually all network elements (with the exception of a few filters, duplexers, and RF amplifiers) being software-defined.
"CROSSMobile: A Cross-Layer Architecture for Next-Generation Wireless Systems" by Bob Iannucci, Patrick Tague, Ole Mengshoel, and Jason Lohn
Silicon Valley Technical Report Series CMU-SV-14-001 — Download PDF