Delay-tolerant network experiments on the meshtest wireless testbed

ABSTRACT

Delay Tolerant Networks (DTNs) are a class of networks in which a contemporaneous end-to-end path from source to destination generally does not exist. Such networks use on a store-carry-forward communication model which relies on the mobility of nodes to transfer data between geographically separated nodes. DTN researchers have relied heavily on simulation for evaluation, due to the difficulty and expense of running live experiments with real devices running real DTN implementations.

MeshTest is a laboratory-based multi-hop wireless testbed that subjects real wireless nodes running real DTN implementations to reproducible mobile scenarios. It uses shielded enclosures and an RF matrix switch to dynamically control the attenuation experienced between pairs of nodes. The testbed is an ideal platform for DTN testing, offering convenient experimental control and data management.

We have installed the DTN2 Reference Implementation on wireless nodes within the testbed, and in this paper, we report on a series of experiments based on the well-known Data MULE model. Specifically, we investigate the effects of buffer limitations on the data MULEs and sensors node, velocity of the data MULEs, and bundle generation size and rate. We report results on message delivery rate and latency for varying experimental parameters. We found that an encounter between nodes does not guarantee a successful data transfer. In our experience, the quality and duration of the link, contention, and load on the nodes all influence its performance.

REFERENCES

• 1: T. Clancy and B. Walker. Meshtest: Laboratory testbed for large wireless topologies. IEEE TridentCOM 2007.
• 2: T. C. Clancy and B. D. Walker. Meshtest: Laboratory-based wireless testbed for large topologies. In IEEE TridentCom 2007, pages 1--6, 2007.
• 3: DARPA Disruption Tolerant Networking Program. http://www.darpa.mil/sto/strategic/dtn.html.
• 4: M. Demmer, E. Brewer, K. Fall, S. Jain, M. Ho, and R. Patra. Implementing Delay Tolerant Networking. Technical Report IRB-TR-04-020, Intel Research Berkeley, 2004.
• 5: UMassDieselNet. http://prisms.cs.umass.edu/dome/.
• 6: DTN Research Group. http://www.dtnrg.org/.
• 7: Philo Juang , Hidekazu Oki , Yong Wang , Margaret Martonosi , Li Shiuan Peh , Daniel Rubenstein, Energy-efficient computing for wildlife tracking: design tradeoffs and early experiences with ZebraNet, Proceedings of the 10th international conference on Architectural support for programming languages and operating systems, October 05-09, 2002, San Jose, California
• 8: K. Scott and S. Burleigh. Bundle Protocol Specification. IETF RFC 5050, 2007.
• 9: KioskNet. http://blizzard.cs.uwaterloo.ca/tetherless/index.php/KioskNet/.
• 10: Roomba MADNeT : A Mobile Ad-Hoc Delay Tolerant Network Testbed. http://dna-pubs.cs.columbia.edu/citation/paperfile/150/reich_MC2R.pdf.
• 11: Earl Oliver , Hossein Falaki, Performance evaluation and analysis of delay tolerant networking, Proceedings of the 1st international workshop on System evaluation for mobile platforms, p.1-6, June 11-11, 2007, San Juan, Puerto Rico [doi>10.1145/1247721.1247722]
• 12: A. Pentland, R. Fletcher, and A. Hasson. DakNet: Rethinking Connectivity in Developing Nations. In IEEE Computer, 2004.
• 13: D. Raychaudhuri, I. Seskar, M. Ott, S. Ganu, K. Ramachandran, H. Kremo, R. Siracusa, H. Liu, and M. Singh. Overview of the ORBIT radio grid testbed for evaluation of next-generation wireless network protocols. IEEE WCNC 2005.
• 14: E. M. Royer, P. M. Melliar-Smith, and L. E. Moser. An analysis of the optimum node density for ad hoc mobile networks. In IEEE ICC 2001, volume 3, pages 857--861, 2001.
• 15: Stuart J. Russell , Peter Norvig, Artificial intelligence: a modern approach, Prentice-Hall, Inc., Upper Saddle River, NJ, 1995
• 16: Sami Network. http://www.snc.sapmi.net/.
• 17: Matthew Seligman , Kevin Fall , Padma Mundur, Storage routing for DTN congestion control: Research Articles, Wireless Communications & Mobile Computing, v.7 n.10, p.1183-1196, December 2007 [doi>10.1002/wcm.v7:10]
• 18: A. Seth, D. Kroeker, M. Zaharia, S. Guo, , and S. Keshav.
• 19: R. Shah, S. Roy, S. Jain, and W. Brunette. Data MULEs: Modeling a Three-tier Architecture for Sparse Sensor Networks. In IEEE SNPA, 2003.
• 20: Tara Small , Zygmunt J. Haas, The shared wireless infostation model: a new ad hoc networking paradigm (or where there is a whale, there is a way), Proceedings of the 4th ACM international symposium on Mobile ad hoc networking & computing, June 01-03, 2003, Annapolis, Maryland, USA [doi>10.1145/778415.778443]
• 21: Tara Small , Zygmunt J. Haas, Resource and performance tradeoffs in delay-tolerant wireless networks, Proceedings of the 2005 ACM SIGCOMM workshop on Delay-tolerant networking, p.260-267, August 26-26, 2005, Philadelphia, Pennsylvania, USA [doi>10.1145/1080139.1080144]
• 22: TIER Project. http://tier.cs.berkeley.edu/.
• 23: Brenton Walker , Charles Clancy, A quantitative evaluation of the MeshTest wireless testbed, Proceedings of the 4th International Conference on Testbeds and research infrastructures for the development of networks & communities, March 18-20, 2008, Innsbruck, Austria
• 24: Wizzy Project. http://www.wizzy.org.za/.
• 25: W. Zhao , M. Ammar , E. Zegura, A message ferrying approach for data delivery in sparse mobile ad hoc networks, Proceedings of the 5th ACM international symposium on Mobile ad hoc networking and computing, May 24-26, 2004, Roppongi Hills, Tokyo, Japan [doi>10.1145/989459.989483]

INDEX TERMS

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

Additional Classification:
  C. Computer Systems Organization
  C.4 PERFORMANCE OF SYSTEMS
      Subjects: Measurement techniques

General Terms:
Algorithms, Experimentation, Performance

Keywords:
delay-tolerant network, meshtest