Cluster Computing

, Volume 1, Issue 2, pp 225–235 | Cite as

Studying vertical dependence to improve NFS performance in wireless networks

  • Cynthia D. Rais
  • Satish K. Tripathi


Wireless networks experience a high level of errors and losses. These physical layer characteristics have an impact on the performance of the higher layers. In addition, the performance of each protocol layer is contingent on the behavior of the other layers. Vertical dependency is a term which describes this inter-dependence between layers. In the wireless and mobile environment, the effects of vertical dependence are particularly pronounced due to the dynamic nature of the environment and due to the fact that traditional assumptions about protocol layer interactions do not always hold. In this paper, we consider the vertical dependencies between various layers in the protocol stack, studying the performance of the Network File System under various error models and improvement techniques. Our experimental results demonstrate the dependency of the application performance on the details of the error characteristics and other protocol layers. After studying the vertical dependencies, we improve NFS performance by implementing changes to the application level reliability mechanisms. Understanding of the vertical dependencies enables development of effective methods for performance enhancement and efficient reaction to errors and changes on the wireless media.


Wireless Link Mobile Host Transport Layer Link Layer Error Pattern 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Kluwer Academic Publishers 1998

Authors and Affiliations

  • Cynthia D. Rais
    • 1
  • Satish K. Tripathi
    • 2
  1. 1.Department of Computer ScienceUniversity of MarylandCollege ParkUSA
  2. 2.Bourns College of EngineeringUniversity of CaliforniaRiversideUSA

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