70 likes | 193 Vues
Trickle: A Self-Regulating Algorithm for Code Propagation and Maintenance in Wireless Sensor Networks. Sections 4.4, 4.5, 5, and 5.1. Load Distribution. Which Motes are sending/Receiving Packets? Evenly Distributed?. Random. Pattern. Empirical Study. Motes on a small table
E N D
Trickle: A Self-Regulating Algorithm for Code Propagation and Maintenance in Wireless Sensor Networks Sections 4.4, 4.5, 5, and 5.1
Load Distribution • Which Motes are sending/Receiving Packets? • Evenly Distributed? Random Pattern
Empirical Study • Motes on a small table • Low transmission signal strength (multi-hop) • Results: Similar to scaling by TOSSIM-bit (should it have compare TOSSIM-packet?) • Redundancy of 1.1 vs. 1.3 (very close)
Propagation • Gossip interval (τ) determines overhead • High τ value means fewer broadcasts; higher delay • Low τ value means more broadcasts; lower delay • Dynamic Scaling of τ • Lower/upper bounds • When τ expires, double it; otherwise reset it • Best of both worlds: • rapid propagation • Low overhead
Trickle Pseudocode • When There’s Nothing New to Say, Gossip Infrequently
Mate, a Trickle Implementation • Allows users to build VMs on TinyOSsesnors • Language + Events + Primitives • Each routine is within 30 bytes • Vector used to keep track of routines • Trickle Implementation: When mote hears an old Vector, it rebroadcasts newer routines three times