1 / 17

Efficient Content Location in MANETs

Efficient Content Location in MANETs. Jivodar Tchakarov Nitin Vaidya Presented by : Jungmin So University of Illinois at Urbana-Champaign. Introduction. Centralized approaches Central directory server Too much dependency on particular nodes Decentralized approaches

marcie
Download Presentation

Efficient Content Location in MANETs

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Efficient Content Location in MANETs Jivodar Tchakarov Nitin Vaidya Presented by: Jungmin So University of Illinois at Urbana-Champaign

  2. Introduction • Centralized approaches • Central directory server • Too much dependency on particular nodes • Decentralized approaches • No central directory server • Not efficient in ad hoc environments

  3. Location-based protocol[Aydin02,Badrinath02] • Propagate advertisements and queries in cross-shaped directions • Nodes at intersections answer queries • Amount of proactive traffic grows with each new server replicas

  4. Location-Based Protocol[Aydin02,Badrinath02] Query Response

  5. Goals of Proposed Protocol • Given multiple replicas, a client should discover a nearby server • Per-replica overhead should decrease when more replicas are added

  6. Proposed Geography-based Content Location (GCLP) Protocol • Basic protocol similar to the previous location-based protocol • Clients advertise and query along selected geographical directions • Nodes (called content location servers) at intersections answer queries • New feature: A node only forwards advertisements from the closest known replica

  7. GCLP Protocol

  8. GCLP Scalability • Nodes only forward advertisements from closest known content server replica • Per replica proactive overhead decreases with increasing number of servers

  9. GCLP • Protocol allows a client to locate a nearby server in most situations, performing best in dense networks • In dense networks, the physical distance to the located server is within 1.5 time the distance to the closest server

  10. Simulations • Using ns-2 simulations • Varied number of nodes (node density) • 2000 m x 2000 m rectangle • Transmission range = 250 m

  11. Performance Measures • Update cost = overhead of propagating updates from the servers • Query cost = cost of determining location of a server in response to queries from clients • Success rate: Fraction of queries that receive a response

  12. Update Cost:Per server update cost decreases with increasing number of servers

  13. Query Cost:Per query cost decreases with increasing number of servers

  14. Success Rate:Increases rapidly with increasing number of servers

  15. Success Rate:Degrades when node density is low

  16. Conclusion • Proposed protocol scales well with increasing number of server replicas • Per-server Overhead decreases • Success rate increases • Performs best when network is dense

  17. Thanks!Authors can be reached atnhv@uiuc.edu

More Related