DIRAC: a software-based wireless router system

ABSTRACT

Routers are expected to play an important role in the IP-based wireless data network. Although a substantial number of techniques have been proposed to improve wireless network performance under dynamic wireless channel conditions and host mobility, a system support framework is still missing. In this paper, we describe DIRAC, a software-based router system that is designed for wireless networks to facilitate the implementation and evaluation of various channel-adaptive and mobility-aware protocols. DIRAC adopts a distributed architecture that is composed of two parts: a Router Core (RC) shared by the wireless subnets, and a Router Agent (RA) at each access point/base station. RAs expose wireless link-layer information to the RC and enforce the control commands issued by the RC. This approach allows the router to make adaptive decisions based on link-layer information feedback. It also permits the router to enforce its policies (e.g., policing) more effectively through underlying link-layer mechanisms. As showcases, we implement under DIRAC the prototypes of three wireless network services: link-layer assisted fast handover, channel-adaptive scheduling, and link-layer enforced policing. Our implementation and experiments show that our distributed wireless router provides a flexible framework, which enables advanced network-layer wireless services that are adaptive to channel conditions and host mobility.

REFERENCES

• 1: Tammo Spalink , Scott Karlin , Larry Peterson , Yitzchak Gottlieb, Building a robust software-based router using network processors, Proceedings of the eighteenth ACM symposium on Operating systems principles, October 21-24, 2001, Banff, Alberta, Canada
• 2: Y. Gottlieb and L. Peterson, "A comparative study of extensible routers," OpenArch'02, June 2002.
• 3: Songwu Lu , Vaduvur Bharghavan , Rayadurgam Srikant, Fair scheduling in wireless packet networks, Proceedings of the ACM SIGCOMM '97 conference on Applications, technologies, architectures, and protocols for computer communication, p.63-74, September 14-18, 1997, Cannes, France
• 4: Thyagarajan Nandagopal , Songwu Lu , Vaduvur Bharghavan, A unified architecture for the design and evaluation of wireless fair queueing algorithms, Proceedings of the 5th annual ACM/IEEE international conference on Mobile computing and networking, p.132-142, August 15-19, 1999, Seattle, Washington, United States [doi>10.1145/313451.313520]
• 5: X. Liu, E.K.P. Chong, And N. B. Shroff, "Transmission Scheduling for Efficient Wireless Network Utilization," INFOCOM'01, April 2000.
• 6: Fast Handovers for Mobile IPv6, draft-ietf-mobileip-fast-mipv6-05.txt, 2002.
• 7: J. Ahn, and J. Heidemann, "An Adaptive FEC Algorithm for Mobile Wireless Networks," Technical Report ISI-TR-555, USC/ISI, March 2002.
• 8: Eddie Kohler , Robert Morris , Benjie Chen , John Jannotti , M. Frans Kaashoek, The click modular router, ACM Transactions on Computer Systems (TOCS), v.18 n.3, p.263-297, Aug. 2000 [doi>10.1145/354871.354874]
• 9: Open AP Platform http://opensource.instant802.com/.
• 10: Rajeev Koodli , Charles E. Perkins, Fast handovers and context transfers in mobile networks, ACM SIGCOMM Computer Communication Review, v.31 n.5, October 2001 [doi>10.1145/1037107.1037113]
• 11: David Kotz , Kobby Essien, Analysis of a campus-wide wireless network, Proceedings of the 8th annual international conference on Mobile computing and networking, September 23-28, 2002, Atlanta, Georgia, USA [doi>10.1145/570645.570659]
• 12: Juniper Research. http://www.juniperresearch.com.
• 13: D. Johnson, C. Perkins, J. Arkko, "Mobility support in IPv6," http://www.ietf.org/internet-drafts/draft-ietf-mobileip-ipv6-18.txt.
• 14: T. Narten, E. Nordmark, and W. Simpson "Neighbor Discovery for IP Version 6 (IPv6)," IETF RFC 2461, December 1998.
• 15: Brian D. Noble , M. Satyanarayanan , Dushyanth Narayanan , James Eric Tilton , Jason Flinn , Kevin R. Walker, Agile application-aware adaptation for mobility, Proceedings of the sixteenth ACM symposium on Operating systems principles, p.276-287, October 05-08, 1997, Saint Malo, France
• 16: Intersil Prism2 driver. http://hostap.epitest.fi/.
• 17: A. Rubini, and J. Corbet, Linux Device Drivers, 2nd Edition, O'REILY, ISBN 0-596-00008-1.
• 18: Hidetoshi Yokota , Akira Idoue , Toru Hasegawa , Toshihiko Kato, Link layer assisted mobile IP fast handoff method over wireless LAN networks, Proceedings of the 8th annual international conference on Mobile computing and networking, September 23-28, 2002, Atlanta, Georgia, USA [doi>10.1145/570645.570661]
• 19: P. McCann "Mobile IPv6 Fast Handovers for 802.11 Networks," http://www.ietf.org/internet-drafts/draft-mccann-mobileip-80211fh-01.txt.
• 20: Mobile IPv6 for Linux. http://www.mipl.mediapoli.com/.
• 21: Luigi Rizzo, Effective erasure codes for reliable computer communication protocols, ACM SIGCOMM Computer Communication Review, v.27 n.2, p.24-36, Apr. 1997 [doi>10.1145/263876.263881]
• 22: "The IA-32 Intel Architecture Software Developer's Manual, Volume 3: System Programming Guide," http://developer.intel.com/design/pentium4/ manuals/245472.htm.
• 23: A. Mishra, M. Shin and W. Arbaugh "An Empirical Analysis of the IEEE 802.11 MAC Layer Handoff Process," Tech Report, UMIACS-TR-2002-75.
• 24: Icecast Streaming Server, http://www.icecast.org/
• 25: David Mosberger , Larry L. Peterson, Making paths explicit in the Scout operating system, Proceedings of the second USENIX symposium on Operating systems design and implementation, p.153-167, October 29-November 01, 1996, Seattle, Washington, United States
• 26: Dan Decasper , Zubin Dittia , Guru Parulkar , Bernhard Plattner, Router plugins: a software architecture for next-generation routers, IEEE/ACM Transactions on Networking (TON), v.8 n.1, p.2-15, Feb. 2000 [doi>10.1109/90.836474]
• 27: XORP: Extensible open router platform. http://www.xorp.org/.
• 28: P. Pradhan and T. Chiueh, "A Cluster-based, Scalable Edge Router Architecture," Technical Report, http://www.ecsl.cs.sunysb.edu/~prashant/papers/ design.ps.gz.
• 29: N. Shalaby, L. Peterson, et al. "Extensible Routers for Active Networks," Tech Report, http://www.cs.princeton.edu/nsg/papers/dance.pdf
• 30: P. Faratin, J. Wroclawski, G. Lee, and S. Parsons, "The Personal Router: An Agent for Wireless Access," AAAI'02, July 2002.
• 31: Vernier Networks System 6500. http://www.verniernetworks.com/AMCS6500.html.
• 32: SpringTide 7000 Wireless IP Service Switch Router. http://www.lucent.com/livelink/0900940380004ac9_Brochure_datasheet.pdf.
• 33: Nomadix Service Engine. http://www.nomadix.com /downloads/products/NSE_Data_Sheet.pdf.
• 34: Aruba 5000. http://www.arubanetworks.com/ products/5000/.
• 35: A. Miu and P. Bahl, "Dynamic host configuration for managing mobility between public and private networks," Usenix Internet Technical Symposium, March 2001.
• 36: M. E. Kounavis, A. T. Campbell, et al, "Design, Implementation and Evaluation of Programmable Handoff in Mobile Networks," MoMuc 2000.
• 37: O. Angin, A. Campbell, et al "The Mobiware Toolkit: Programmable Support for Adaptive Mobile Networking," IEEE Personal Communications Magazine, August 1998.

INDEX TERMS

Primary Classification:
  C. Computer Systems Organization
  C.2 COMPUTER-COMMUNICATION NETWORKS
      C.2.1 Network Architecture and Design

General Terms:
Design, Experimentation, Performance

Keywords:
distributed router architecture, wireless network