However, this will cause energy waste. Alternately, more
e?±cient quorums should be selected to cut down overhead while maintaining
high quality performance of both updates and requests.
Generally, the sensing scopes by di?®erent nodes are more likely to overlap
due to the unattended nature of sensor infrastructure, and the sensed information
is much larger in volume. There is no need to refresh each piece of integral
produced information to others every time. This is di?®erent from location
service. Therefore negotiation can be combined with. By negotiation, integral
data are updated in the source (sensed sensor) only. A meta description about
the data regarded as advertisement is disseminated to its write quorum. Later,
when destination search is transmitted within a read quorum, the rendezvous
can help match the request with recorded advertisements. With the location
provided in advertisement, request packets can correctly reach the source. Finally,
the complete information can be obtained from the source. Negotiation
helps reduce the tra?±c in disseminating redundant or duplicate data.
3.1 Traditional Protocols
There are many previous protocols to solve this information dissemination
problem. The simplest one is by flooding. Such a straightforward protocol is
stateless and it disseminates information quickly in a network. However, it
incurs heavy cost and a message implosion problem.
To overcome the deficiencies of the classic flooding, Heinzelman et al
[23] proposed a family of adaptive protocols for information dissemination
in WSNs, called Sensor Protocols for Information via Negotiation (SPIN).
Pages:
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398