Compressing backoff in CSMA networks

Mahanth Gowda, Nirupam Roy, Romit Roy Choudhury, Srihari Nelakuditi

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Randomized backoff is a well-established approach for avoiding collisions in CSMA networks. Today's backoff operation, such as in WiFi, attempts to create a total ordering among all the nodes contending for the channel. Total ordering requires assigning a unique backoff to each node, which is achieved by having nodes choose their back-offs from a large range, ultimately leading to channel wastage. This paper observes that total ordering can be achieved more efficiently. We propose 'hierarchical backoff' in which nodes pick random numbers from a smaller range, resulting in groups of nodes picking the same number (i.e., partial order). Now, the group of nodes that picks the smallest number is advanced to a second round, where they again perform the same operation. This results in more efficient backoff because the time for partially ordering all nodes plus totally ordering each small groups is actually less than the time needed to totally order all nodes. Realizing the above intuition requires addressing new protocol challenges in group signaling, the feasibility of which is demonstrated on a USRP/GNUradio prototype. Large scale simulations also show consistent throughput gains by incorporating the proposed backoff approach into two CSMA protocols - WiFi and oCSMA. We also show that the proposed approach can be complementary to and even outperform existing backoff optimization schemes.

Original languageEnglish (US)
Title of host publication2016 IEEE 24th International Conference on Network Protocols, ICNP 2016
PublisherIEEE Computer Society
ISBN (Electronic)9781509032815
DOIs
StatePublished - Dec 14 2016
Event24th IEEE International Conference on Network Protocols, ICNP 2016 - Singapore, Singapore
Duration: Nov 8 2016Nov 11 2016

Publication series

NameProceedings - International Conference on Network Protocols, ICNP
Volume2016-December
ISSN (Print)1092-1648

Other

Other24th IEEE International Conference on Network Protocols, ICNP 2016
CountrySingapore
CitySingapore
Period11/8/1611/11/16

Fingerprint

Carrier sense multiple access
Network protocols
Throughput

All Science Journal Classification (ASJC) codes

  • Computer Networks and Communications
  • Software

Cite this

Gowda, M., Roy, N., Choudhury, R. R., & Nelakuditi, S. (2016). Compressing backoff in CSMA networks. In 2016 IEEE 24th International Conference on Network Protocols, ICNP 2016 [7784437] (Proceedings - International Conference on Network Protocols, ICNP; Vol. 2016-December). IEEE Computer Society. https://doi.org/10.1109/ICNP.2016.7784437
Gowda, Mahanth ; Roy, Nirupam ; Choudhury, Romit Roy ; Nelakuditi, Srihari. / Compressing backoff in CSMA networks. 2016 IEEE 24th International Conference on Network Protocols, ICNP 2016. IEEE Computer Society, 2016. (Proceedings - International Conference on Network Protocols, ICNP).
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Gowda, M, Roy, N, Choudhury, RR & Nelakuditi, S 2016, Compressing backoff in CSMA networks. in 2016 IEEE 24th International Conference on Network Protocols, ICNP 2016., 7784437, Proceedings - International Conference on Network Protocols, ICNP, vol. 2016-December, IEEE Computer Society, 24th IEEE International Conference on Network Protocols, ICNP 2016, Singapore, Singapore, 11/8/16. https://doi.org/10.1109/ICNP.2016.7784437

Compressing backoff in CSMA networks. / Gowda, Mahanth; Roy, Nirupam; Choudhury, Romit Roy; Nelakuditi, Srihari.

2016 IEEE 24th International Conference on Network Protocols, ICNP 2016. IEEE Computer Society, 2016. 7784437 (Proceedings - International Conference on Network Protocols, ICNP; Vol. 2016-December).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

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Gowda M, Roy N, Choudhury RR, Nelakuditi S. Compressing backoff in CSMA networks. In 2016 IEEE 24th International Conference on Network Protocols, ICNP 2016. IEEE Computer Society. 2016. 7784437. (Proceedings - International Conference on Network Protocols, ICNP). https://doi.org/10.1109/ICNP.2016.7784437