Cross-Layered Approach for (m,k)-Firm Stream in Wireless Sensor Networks

Abstract

Asmostsensornodesaredeployedtodetectandtransmitinterestingeventsorphenomenaaroundthem,thereal-timedeliveryofsensedinformationwithinapredetermineddeadlinebecomesoneofthebiggestchallengesinwirelesssensornetworks.Eventhoughsomeoftherecentresearchworkshavebeenpublishedinspecificfield,theyaredesignedtocovergeneralpurposeapplications.Therefore,mostofapplicationscannotbesupportedbyexistingschemesespeciallywhentherequirementisapplication-specificreal-time.Inorder tosolvethisproblem,wemodelthetargetapplicationasaspecifictraffic,(m,k)-firmstream, whichisknownashardreal-timerequirement,andthenproposeaschemetoguaranteerealtimedelivery.Todevelopthese,weintroduceacross-layerdesigntobringcollaboration betweenlayersunderthebasicprinciplethatreal-timedeliverywillhardlyachievebyindependentschemeineachlayer.Thus,therequirementsofapplicationarepassedtolowerlayersandusedtoadjusttransmissionpower,prioritizepackets,andfindtheadequatepathinordertomeet(m,k)-firmconstraintsforanystreamdynamically.Finally,simulationresultsrevealthatlowfailureprobabilityforreal-timerequirementson(m,k)-firmstreamisachievedbytheproposedscheme.