ABSTRACTIngeneral, Quality of Service requirements are different for applications implementedon the same wireless sensor network platform. The two requirements offundamentals in such network platforms there are high data integrity and lowdelay.
Moreover, in situations is many, these two basic requirements need notbe simultaneously satisfied. In this area of research we suggest IDDR servicealgorithm to the conflicts is resolved build on the physics potential concept.The IDDR can separate the applications packets with non-similar quality ofservice requirements by constructing hybrid potential field virtually. Accordingto the assigned weight of each packet it is possible to construct a virtualenvironment and route the packets the sink towards from different paths and canimprove the fidelity of data as well to minimize end-to-end delay fordelay-sensitive and integrity sensitive applications. The suggested algorithmIDDR is stable when implemented with the technique called Lyapurnov drift. Thepaper also proved that IDDR service can provide integrity of data anddifferentiated services delay through simulation.
1. INTRODUCTIONWirelessSensor Networks in short WASN’s are mainly used for physical world sensing,which can play a vital part in the future generation networks. The researchcommunity is concentrating on quality of service guarantee in wireless sensornetworks because of complexity and diversity of applications.
As a part ofcommunication infrastructure, WASN’s must be molded in a way that can supportdifferent applications of the platform is same. It is because different informationinfrastructure will have various QoS requirements. High data integrity and low delayare the major requirements of QoS which can further lead to delay-sensitive andhigh-integrity applications. In general, a network with a heavy load can suffercongestion and may increase end-to-end delays and light loaded networks do notsuffer any congestion and readily satisfied.
To overcome such issues we adoptthe discipline of physics called potential field. A routing algorithm isdesigned based on potential field is called IDDR abbreviated as Integrity-DelayDifferentiation routing. IDDR is capable to prove two main functionalities suchas1. ImproveFidelity: The main idea of IDDR is to improve the fidelity of the applicationswith high-integrity by finding buffer space as much as possible by catching thepackets are excessive from idle/under-loaded paths that might be slippedtransferred through the shortest path. So the step first is to identify suchidle or under-loaded paths and later to cache the additional data packets forefficient transmission. IDDR contribute to do so by constructing a potentialfield keeping in the view of information about the path is depth and queuelength to find such paths.
Through smaller queue lengths the excessive datapackets are sent to the next hop. To improve the efficiency a mechanism calledIHoHRC is defined. IHoHRC is an Implicit Hop-Hop Rate Control which can catchthe packets more efficiently.
2. DecreaseDelay: Each application at the time of development assigns certain weight forrepresenting the delay of degree is sensitivity. IDDR allows the data packetsto transfer through shorter paths if they have larger weights and employs thedecreasing of queuing sensitive packets delay.IDDRavoids the conflicts between the low delay and high-integrity by catching thepackets having larger delay and more hops. High integrity data packets is underloaded paths are also cached and makes them to transmit in a shorter path sothat they can reach the sink as early as possible. The other sections of the research paperare organized as chapter’s related work and motivation, IDDR Design andexperimental setup.
2.BACKGROUND STUDYResourcereservation and end-to-end discovery 3 of path can cause larger overhead fortraditional ad-hoc networks. Most of the QoS protocols in these ad-hoc networksare not suitable to WASN’s resource-constrained. Few mechanisms to support QoSservices have been specially designed for wireless sensor networks mainly byconsidering delay and reliability metrics. 1. Real-TimeService support: RAP utilize the velocity notion and suggest a policy ofscheduling velocity-monitoring and minimizes the missed deadlines ratio 11 butrequires network topology information. Implicit EDF majorly utilizes a mediumof protocol to access control and to supply real-time services 9. A desiredspeed of delivery is maintained across the network is used to implicitprioritization instead of control packets rely through a novel mixture ofnon-deterministic and feedback control QoS geographic forwarding 8.
To enhanceperformance in real-time information based two-hop neighbor gradient routingmechanism was suggested. The mechanism takes a decision of routing based on thehops count from a sources to sink and information about two-hop.2. ReliabilityService Support: AFS engage the priority of packets to control reliability bydetermining the forwarding behavior. Reinform utilize the concept calleddynamic states of packets for the reliability desired and to control therequired number of paths. The common feature among these two concepts is theyrequire being aware of global network topology. The next mechanism calleddynamic path maintenance LIEMRO 6 monitors the qualityof active paths which network operations are running without considering thebuffer effect and rate of service to predict and adjust the rate of traffic forthe active nodes.
3. Reliability andReal-Time Service support: It utilized the mechanism of SPEED 8 and satisfiesdelay requirement for various traffic types by using redundant paths to the reliabilityis safeguard. During the network congestion all the nodes from sourcetransmitpackets along the multi paths to the sink without considering any mechanism oftransmission.(a) SPT Actions (b)Multipath Routing Actions Figure 1: IDDR Motivation Smallportion of WASN is clearly visible in Figure 1. In this figure if node 1 isassumed to be a hotspot with delay-sensitive packets represented with solidrectangles and high-integrity packets represented with hollow rectangles fromA,B and C source nodes.
A common routing algorithm is used to choose an optimalpath to transmit for all the transferring packets. Figure 1(a) is showing thestandard tree of shortest path routing which can forward all the packetsthrough node 1. In this case large end-to-end delay and high-integrity packetscan loss due to congestion for delay-sensitive packets. To avoid hotspots analgorithm multi-path routing is implemented to utilize many other paths asshown in the Figure 1(b). However, this can hardly met the high throughput and simultaneouslylow delay. To overcome these issues, we aim to design mechanism which can allowthe packets with delay-sensitivity to transfer through the shortest path andavoid feasible dropping of hotspots. This concept motivated us to suggest theIDDR scheme based on an algorithm called dynamic multipath routing. Figure2(a) node 1 cannot choose high-integrity packets due to its long queue length.
Fewother paths which are idle/under loaded, such as 2 ? 3 ? Sink and 4 ? 5 ? 6 ?Sink, are utilized to cache packets and efficiently route them efficiently and protectfrom being unhold in the hotspot. And the other side, IDDR providespackets withdelay-sensitive priority to move ahead in the path is shortest and achieve low delay. Furthermore, on theshortest path if the traffic is heavy, then IDDR can select alternate paths fordelay-sensitive packets, like the path: A ? 4 ? 5 ? 6 ?Sink which is depicted inthe Figure 2(b), the link to the sink from node 1 is busy so that node A/B willbypass node 1 and transfer packets along the alternate under-utilized paths tothe sink to avoid dropped packets. (a) SPT Actionson the shortest path and withouthotspots (b) Multipath RoutingActions without hotspots on the shortest paths Figure 2: IDDR Motivation withoutHotspots 3.IDDR DESIGNWe atfirst describe the IDDR based potential fields and specify how a potentialfieldcan improve the fidelity of data and decrease the delay of packets end-to-end. 1.
Potential Fields designa. Potentialfield model: Designed for existing wire line networks and to view the gravityfield of the entire network.b.
Depthof potential field: To provide the fundamental routing function.c. Lengthof potential queue field: To define the length of potential queue field of anynode with respect of time.d. Hybridpotential field: To build a virtual and hybrid potential based on the queuelength and depth of the defined field. 2. High Integrity servicesa.
Discoveryof resources: To provide the applications a high integrity services and to discoverthe resources to identify the shortest path.b. Implicithop-to-hop rate control: Defined to detect the hotspot with no shortest pathdoes not exist and send the packets through sub optional path.3.
Delay-Differentiated servicesa. Hybridpotential field slope: The service is to identify the factors affect the delayof transmission, radio channel competition, queuing delay, and length of thepath. Meanwhile the service is used to define the depth and the slope of apotential field.b. Weightof the packet: It represents a level of delay sensitivity each packet with8-bit header.
c. Queuepriority: It is used to minimize the queuing delay by deploying IDDR priorityqueue mechanism. 4.
IDDR algorithma. IDDRprocedure: The procedure considers various WASN delay-sensitive andhigh-integrity applications.b. Potentialfield depth construction: Define the depth of potential field by providingfundamental routing function.
c. Signaling:Updates the queue length and depth of the potential field among the neighborsand imprecise the information. 4.CONCLUSIONInthis journal, an IDDR algorithm called dynamic multipath routing is suggestedto satisfy two various requirements of QoS over the same wireless ad-hoc sensornetworks simultaneously. Utilizing the theory of Lyapurnov drift it was provedthat the IDDR algorithm is stable.
Meanwhile it was proved that the IDDR algorithmcan improve applications with high-integrity and reduce the delay of sensitiveand end-to-end applications.