Pub Date : 2008-12-01DOI: 10.1109/ATNAC.2008.4783327
S. Habib, Maytham Safar, Nosayba El-Sayed
This work explores the automatic placement of actors within wireless sensor-actor network through an evolutionary approach. A wireless sensor network (WSN) consists of two sets of nodes: sensors and actors, where the set of sensors performs all the sensing (data collection) from their surrounding environment. Since sensors operate by batteries, then they are limited with their processing and communication capabilities due to the short life-span of the batteries. On the other hand, the set of actors has more capabilities with extended life-span batteries, and their roles are to collect and process the raw data from the sensors to determine the next action for WSN. The actor placement problem is to select a minimal set of actors and their optimal locations in WSN keeping in mind the communication requirements between sensors and actors. We have encoded the actor placement problem into the evolutionary approach, where the objective function is to find the minimal total number of actors covering as many sensors as possible subject to budgetary and performance constraints. The experimental results demonstrate the feasibility of our evolutionary approach in covering 77% of 61 sensors by three actors within an area of 375 meters by 375 meters.
{"title":"Automatic Placement of Actors within Wireless Sensor-Actor Networks","authors":"S. Habib, Maytham Safar, Nosayba El-Sayed","doi":"10.1109/ATNAC.2008.4783327","DOIUrl":"https://doi.org/10.1109/ATNAC.2008.4783327","url":null,"abstract":"This work explores the automatic placement of actors within wireless sensor-actor network through an evolutionary approach. A wireless sensor network (WSN) consists of two sets of nodes: sensors and actors, where the set of sensors performs all the sensing (data collection) from their surrounding environment. Since sensors operate by batteries, then they are limited with their processing and communication capabilities due to the short life-span of the batteries. On the other hand, the set of actors has more capabilities with extended life-span batteries, and their roles are to collect and process the raw data from the sensors to determine the next action for WSN. The actor placement problem is to select a minimal set of actors and their optimal locations in WSN keeping in mind the communication requirements between sensors and actors. We have encoded the actor placement problem into the evolutionary approach, where the objective function is to find the minimal total number of actors covering as many sensors as possible subject to budgetary and performance constraints. The experimental results demonstrate the feasibility of our evolutionary approach in covering 77% of 61 sensors by three actors within an area of 375 meters by 375 meters.","PeriodicalId":143803,"journal":{"name":"2008 Australasian Telecommunication Networks and Applications Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128765786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-12-01DOI: 10.1109/ATNAC.2008.4783321
S. M. Rokonuzzaman, R. Pose, I. Gondal
The capacity of wireless ad hoc networks can be increased by using multiple radio channels. But due to interference the capacity is still not fully utilized. This is caused by the limited number of available radio channels. The interference problem can be reduced using directional beams instead of omni-directional beams. This paper presents a novel cross-layer approach to use multiple radio channels with directional antennas. We are using three different radio channels. Each node has three fixed directional beams having fixed beamwidth and with different radio frequency. Two nodes can communicate when both the sending and receiving beams are pointing towards each other using the same frequency channel. In this study the directions of beams cannot be changed dynamically. A modified version of ad hoc on-demand distance vector (AODV) routing protocol has been used. Simulation results show that our approach outperforms other methods using three different radio channels with omni-directional antennas.
{"title":"A Cross-layer Approach for Using Multiple Radio Channels with Directional Beams in a Suburban Ad Hoc Network","authors":"S. M. Rokonuzzaman, R. Pose, I. Gondal","doi":"10.1109/ATNAC.2008.4783321","DOIUrl":"https://doi.org/10.1109/ATNAC.2008.4783321","url":null,"abstract":"The capacity of wireless ad hoc networks can be increased by using multiple radio channels. But due to interference the capacity is still not fully utilized. This is caused by the limited number of available radio channels. The interference problem can be reduced using directional beams instead of omni-directional beams. This paper presents a novel cross-layer approach to use multiple radio channels with directional antennas. We are using three different radio channels. Each node has three fixed directional beams having fixed beamwidth and with different radio frequency. Two nodes can communicate when both the sending and receiving beams are pointing towards each other using the same frequency channel. In this study the directions of beams cannot be changed dynamically. A modified version of ad hoc on-demand distance vector (AODV) routing protocol has been used. Simulation results show that our approach outperforms other methods using three different radio channels with omni-directional antennas.","PeriodicalId":143803,"journal":{"name":"2008 Australasian Telecommunication Networks and Applications Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126741936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-12-01DOI: 10.1109/ATNAC.2008.4783319
J.C.-P. Wang, D. Franklin, M. Abolhasan, F. Safaei
This paper investigates the relative performance of unicast and broadcast traffic traversing a one-hop ad hoc network utilising the 802.11 DCF. An extended Markov model has been developed and validated through computer simulation, which successfully predicts the respective performance of unicast and broadcast in a variety of mixed traffic scenarios. Under heavy network traffic conditions, a significant divergence is seen to develop between the performance of the two traffic classes - in particular, when network becomes saturated, unicast traffic is effectively given higher precedence over broadcast. As a result, the network becomes dominated by unicast frames, leading to poor rates of broadcast frame delivery.
{"title":"Characterising the Interactions Between Unicast and Broadcast in IEEE 802.11 Ad Hoc Networks","authors":"J.C.-P. Wang, D. Franklin, M. Abolhasan, F. Safaei","doi":"10.1109/ATNAC.2008.4783319","DOIUrl":"https://doi.org/10.1109/ATNAC.2008.4783319","url":null,"abstract":"This paper investigates the relative performance of unicast and broadcast traffic traversing a one-hop ad hoc network utilising the 802.11 DCF. An extended Markov model has been developed and validated through computer simulation, which successfully predicts the respective performance of unicast and broadcast in a variety of mixed traffic scenarios. Under heavy network traffic conditions, a significant divergence is seen to develop between the performance of the two traffic classes - in particular, when network becomes saturated, unicast traffic is effectively given higher precedence over broadcast. As a result, the network becomes dominated by unicast frames, leading to poor rates of broadcast frame delivery.","PeriodicalId":143803,"journal":{"name":"2008 Australasian Telecommunication Networks and Applications Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126202911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-12-01DOI: 10.1109/ATNAC.2008.4783347
N. Wongvanich, H. Sirisena
This paper presents an adaptive sliding window flow control protocol for MPLS networks, based on estimating the available link bandwidth using Kalman Filtering enhanced by bias estimation. An optimal control algorithm is then implemented that minimizes the variance of queue length deviations from the desired target. The simulation results show that, with bias estimation, the bandwidth estimate converges much faster than with ordinary Kalman filtering. We also achieve the goal of maximizing the bandwidth link utilization efficiency while minimizing the packet loss rate.
{"title":"Adaptive Window Flow Control in MPLS Networks using Enhanced Kalman Filtering","authors":"N. Wongvanich, H. Sirisena","doi":"10.1109/ATNAC.2008.4783347","DOIUrl":"https://doi.org/10.1109/ATNAC.2008.4783347","url":null,"abstract":"This paper presents an adaptive sliding window flow control protocol for MPLS networks, based on estimating the available link bandwidth using Kalman Filtering enhanced by bias estimation. An optimal control algorithm is then implemented that minimizes the variance of queue length deviations from the desired target. The simulation results show that, with bias estimation, the bandwidth estimate converges much faster than with ordinary Kalman filtering. We also achieve the goal of maximizing the bandwidth link utilization efficiency while minimizing the packet loss rate.","PeriodicalId":143803,"journal":{"name":"2008 Australasian Telecommunication Networks and Applications Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132758959","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-12-01DOI: 10.1109/ATNAC.2008.4783359
M. Asgari, A. Sayadian, M. Farhadloo, E. A. Mehrizi
In this paper we develop a voice activity detection algorithm based on entropy estimation of magnitude spectrum. In addition, the likelihood ratio test (LRT) is employed to determine a threshold to separate of speech segments from non-speech segments. The distributions of entropy magnitude of clean speech and noise signal are assumed to be Gaussian. The application of the concept of entropy to the speech detection problem is based on the assumption that the signal spectrum is more organized during speech segments than during noise segments. One of the main advantages of this method is that it is not very sensitive to the changes of noise level. Our simulation results show that the entropy based VAD is high performance in low signal to noise ratio (SNR) conditions (SNR < 0 dB).
{"title":"Voice Activity Detection Using Entropy in Spectrum Domain","authors":"M. Asgari, A. Sayadian, M. Farhadloo, E. A. Mehrizi","doi":"10.1109/ATNAC.2008.4783359","DOIUrl":"https://doi.org/10.1109/ATNAC.2008.4783359","url":null,"abstract":"In this paper we develop a voice activity detection algorithm based on entropy estimation of magnitude spectrum. In addition, the likelihood ratio test (LRT) is employed to determine a threshold to separate of speech segments from non-speech segments. The distributions of entropy magnitude of clean speech and noise signal are assumed to be Gaussian. The application of the concept of entropy to the speech detection problem is based on the assumption that the signal spectrum is more organized during speech segments than during noise segments. One of the main advantages of this method is that it is not very sensitive to the changes of noise level. Our simulation results show that the entropy based VAD is high performance in low signal to noise ratio (SNR) conditions (SNR < 0 dB).","PeriodicalId":143803,"journal":{"name":"2008 Australasian Telecommunication Networks and Applications Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115384456","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-12-01DOI: 10.1109/ATNAC.2008.4783337
Tomasz Mrugalski, J. Wozniak
The first generation of fully conformant IEEE 802.16-based networks is being deployed throughout the world. Most of these networks do not support full mobility, due to radio access layer limitations. Newer solutions, based on IEEE 802.16-2005 standard, offer mobility support for subscriber stations. Unfortunately, after quickly changing the point of attachment on the WiMAX layer, very slow and inefficient IPv6 reconfiguration takes place. Delays introduced by DHCPv6 stateless automatic configuration and mobile IPv6 can easily diminish or even render useless all benefits gained using the efficient WiMAX - data link layer. IPv6 automatic configuration process was not designed with fast reconfiguration in mind. As handover speed is a crucial requirement in mobile cellular environments, reasons behind delays introduced by IPv6 layer mechanisms have to be analyzed and appropriate countermeasures applied. Proposals include novel use of DHCPv6 relays for remote configuration, solving DAD delays, limiting Binding Update procedure in Mobile IPv6, configuring routing through DHCPv6 communication and some other. This paper describes all stages of full IPv6 handover in IEEE 802.16 environment, focusing on major reasons of reconfiguration delays. A new metric for assessing impact of every stage on handover efficiency is defined. Several proposed improvements to the IPv6 handover process are evaluated and simulation results are presented. A discussion regarding possible generalization of best improvement proposals and further research areas concludes this paper.
{"title":"How to Improve the Efficiency of IPv6 Handovers in IEEE 802.16 Networks","authors":"Tomasz Mrugalski, J. Wozniak","doi":"10.1109/ATNAC.2008.4783337","DOIUrl":"https://doi.org/10.1109/ATNAC.2008.4783337","url":null,"abstract":"The first generation of fully conformant IEEE 802.16-based networks is being deployed throughout the world. Most of these networks do not support full mobility, due to radio access layer limitations. Newer solutions, based on IEEE 802.16-2005 standard, offer mobility support for subscriber stations. Unfortunately, after quickly changing the point of attachment on the WiMAX layer, very slow and inefficient IPv6 reconfiguration takes place. Delays introduced by DHCPv6 stateless automatic configuration and mobile IPv6 can easily diminish or even render useless all benefits gained using the efficient WiMAX - data link layer. IPv6 automatic configuration process was not designed with fast reconfiguration in mind. As handover speed is a crucial requirement in mobile cellular environments, reasons behind delays introduced by IPv6 layer mechanisms have to be analyzed and appropriate countermeasures applied. Proposals include novel use of DHCPv6 relays for remote configuration, solving DAD delays, limiting Binding Update procedure in Mobile IPv6, configuring routing through DHCPv6 communication and some other. This paper describes all stages of full IPv6 handover in IEEE 802.16 environment, focusing on major reasons of reconfiguration delays. A new metric for assessing impact of every stage on handover efficiency is defined. Several proposed improvements to the IPv6 handover process are evaluated and simulation results are presented. A discussion regarding possible generalization of best improvement proposals and further research areas concludes this paper.","PeriodicalId":143803,"journal":{"name":"2008 Australasian Telecommunication Networks and Applications Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123010625","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-12-01DOI: 10.1109/ATNAC.2008.4783355
B. Vankeirsbilck, P. Simoens, J. De Wachter, L. Deboosere, F. De Turck, B. Dhoedt, P. Demeester
This paper presents graphical update caching as a mechanism to reduce the network load generated by thin client computing systems. In such system, the user interaction and processing are separated by a network. User input such as keystrokes and mouse clicks are sent to the server over the network and graphical updates are transported the reverse way. The cache proposed in this article is static, meaning that it is composed before the thin client computing session starts and that the cache does not change during the session. Through experiments with an implementation of the cache, we show that graphical update caching effectively reduces the network load generated by thin client computing.
{"title":"Bandwidth Optimization for Mobile Thin Client Computing through Graphical Update Caching","authors":"B. Vankeirsbilck, P. Simoens, J. De Wachter, L. Deboosere, F. De Turck, B. Dhoedt, P. Demeester","doi":"10.1109/ATNAC.2008.4783355","DOIUrl":"https://doi.org/10.1109/ATNAC.2008.4783355","url":null,"abstract":"This paper presents graphical update caching as a mechanism to reduce the network load generated by thin client computing systems. In such system, the user interaction and processing are separated by a network. User input such as keystrokes and mouse clicks are sent to the server over the network and graphical updates are transported the reverse way. The cache proposed in this article is static, meaning that it is composed before the thin client computing session starts and that the cache does not change during the session. Through experiments with an implementation of the cache, we show that graphical update caching effectively reduces the network load generated by thin client computing.","PeriodicalId":143803,"journal":{"name":"2008 Australasian Telecommunication Networks and Applications Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129569655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-12-01DOI: 10.1109/ATNAC.2008.4783306
M. Farhadloo, A. Sayadian, M. Asgari, A. Mostafavi
Suppression of additive noise from speech signal is a fundamental problem in audio signal processing. We present in this paper a novel algorithm for single channel speech enhancement. The algorithm consists of two steps: First, estimation of the noise power spectrum with a multi quantile method and second, elimination of the estimated noise from the observed signal by spectral subtraction or Wiener filtering. In this method, instead of a global quantile for all frequency bands, we divide the entire frequency band into three regions and use different quantile in each region. Our simulation results show that the new method has better performance than quantile based noise estimation.
{"title":"Causal Multi Quantile Noise Spectrum Estimation for Speech Enhancement","authors":"M. Farhadloo, A. Sayadian, M. Asgari, A. Mostafavi","doi":"10.1109/ATNAC.2008.4783306","DOIUrl":"https://doi.org/10.1109/ATNAC.2008.4783306","url":null,"abstract":"Suppression of additive noise from speech signal is a fundamental problem in audio signal processing. We present in this paper a novel algorithm for single channel speech enhancement. The algorithm consists of two steps: First, estimation of the noise power spectrum with a multi quantile method and second, elimination of the estimated noise from the observed signal by spectral subtraction or Wiener filtering. In this method, instead of a global quantile for all frequency bands, we divide the entire frequency band into three regions and use different quantile in each region. Our simulation results show that the new method has better performance than quantile based noise estimation.","PeriodicalId":143803,"journal":{"name":"2008 Australasian Telecommunication Networks and Applications Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124586761","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-12-01DOI: 10.1109/ATNAC.2008.4783338
A. Kist
Infrastructure meshed networks provide access to wireless clients that do not participate in traffic forwarding. This paper proposes minimalist instant handoff for wireless access networks (MIHAN), allowing for seamless movement of nodes in coverage areas, while maintaining connectivity. The approach of MIHAN is that all client frames, send in radio range of an access node, are received and forwarded to a central gateway. The node removes duplicate packets and tracks the network attachment of wireless clients. MIHAN relies on standard medium access control and a TCP/IP protocol stack. It is transparent to and does not require any special support, in the clients. Only limited configuration changes are necessary in the access nodes; all routing and tracking is handled by the gateway. Advantages include instant handoffs, no changes to access points and protocols and the simplicity of the solution. The paper introduces the scheme, provides details on various implementation options and gives simulation results that show the operation. Proof of concept implementation and some test results are presented.
{"title":"Instant Handoffs for Wireless Infrastructure Meshed Networks","authors":"A. Kist","doi":"10.1109/ATNAC.2008.4783338","DOIUrl":"https://doi.org/10.1109/ATNAC.2008.4783338","url":null,"abstract":"Infrastructure meshed networks provide access to wireless clients that do not participate in traffic forwarding. This paper proposes minimalist instant handoff for wireless access networks (MIHAN), allowing for seamless movement of nodes in coverage areas, while maintaining connectivity. The approach of MIHAN is that all client frames, send in radio range of an access node, are received and forwarded to a central gateway. The node removes duplicate packets and tracks the network attachment of wireless clients. MIHAN relies on standard medium access control and a TCP/IP protocol stack. It is transparent to and does not require any special support, in the clients. Only limited configuration changes are necessary in the access nodes; all routing and tracking is handled by the gateway. Advantages include instant handoffs, no changes to access points and protocols and the simplicity of the solution. The paper introduces the scheme, provides details on various implementation options and gives simulation results that show the operation. Proof of concept implementation and some test results are presented.","PeriodicalId":143803,"journal":{"name":"2008 Australasian Telecommunication Networks and Applications Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131465722","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-12-01DOI: 10.1109/ATNAC.2008.4783330
S.A. Howlader, M. Frater, M. Ryan
Long-delay networks (LDNs) are networks in which the propagation wave speed is lower than that of radio waves, such as in underwater acoustic networks (UANs). The number of nodes is normally large in such a sensor network and the number may very due to different factors such as power failure or environmental disasters. An identification procedure is needed in this network to observe which nodes are currently operational and a large amount of time can be wasted in every probe of the procedure due to the long propagation delay. Optimizing the number of probes improves the identification time and power consumption by 75% and 60% respectively in both the slotted and un-slotted cases [1]. While optimizing the number of probes for the long delay, the frame size (the time within which the nodes send their packets) increases due to the lower offered load. In this work we show that even with the limitation of the maximum frame size our procedure works well. One of the limitations of LDNs is the variation of the propagating wave speed. We observe that if the standard deviation of the propagation speed is approximately less than 1/e of the packet size then the identification procedure for the slotted case is better than that for the un-slotted case. In order to alleviate the effect of variation in propagation speed we use a guard time in the slotted case.
{"title":"Optimizing Sensor Identification in Long-delay Networks to Account for Maximum Frame Size and Variations in Propagation Speed","authors":"S.A. Howlader, M. Frater, M. Ryan","doi":"10.1109/ATNAC.2008.4783330","DOIUrl":"https://doi.org/10.1109/ATNAC.2008.4783330","url":null,"abstract":"Long-delay networks (LDNs) are networks in which the propagation wave speed is lower than that of radio waves, such as in underwater acoustic networks (UANs). The number of nodes is normally large in such a sensor network and the number may very due to different factors such as power failure or environmental disasters. An identification procedure is needed in this network to observe which nodes are currently operational and a large amount of time can be wasted in every probe of the procedure due to the long propagation delay. Optimizing the number of probes improves the identification time and power consumption by 75% and 60% respectively in both the slotted and un-slotted cases [1]. While optimizing the number of probes for the long delay, the frame size (the time within which the nodes send their packets) increases due to the lower offered load. In this work we show that even with the limitation of the maximum frame size our procedure works well. One of the limitations of LDNs is the variation of the propagating wave speed. We observe that if the standard deviation of the propagation speed is approximately less than 1/e of the packet size then the identification procedure for the slotted case is better than that for the un-slotted case. In order to alleviate the effect of variation in propagation speed we use a guard time in the slotted case.","PeriodicalId":143803,"journal":{"name":"2008 Australasian Telecommunication Networks and Applications Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120858911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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