Pub Date : 2006-08-07DOI: 10.1109/WOCN.2006.1666550
Masakazu Ono, Tatsuya Hirakawa, Hiroaki Higaki
This paper has proposed a method to realize k-resilient distributed stable storage in a checkpoint protocol for a wireless multi-hop access network. By using the method, state information of a mobile computer is stored into storage devices in neighbor mobile computers and less state information is stored into a stable storage in a base station. Hence, communication and storage overhead are reduced. The method is able to be applied to a 3-phase checkpoint protocol without any additional messages. For further reduction of the overhead, not only 1-hop neighbor but also 2-hop neighbor mobile computers are involved into achieving the distributed stable storages. We design a checkpoint protocol by using the proposed method. In simulation evaluation, only 10-20% storage overhead of a naive method storing all state information into a stable storage in a base station is required. Especially in case of sparser mobile computer distribution and higher failure ratio, our extension involving 2-hop neighbor mobile computers works efficiently for reduction of the overhead
{"title":"Stable storage for wireless multi-hop access networks","authors":"Masakazu Ono, Tatsuya Hirakawa, Hiroaki Higaki","doi":"10.1109/WOCN.2006.1666550","DOIUrl":"https://doi.org/10.1109/WOCN.2006.1666550","url":null,"abstract":"This paper has proposed a method to realize k-resilient distributed stable storage in a checkpoint protocol for a wireless multi-hop access network. By using the method, state information of a mobile computer is stored into storage devices in neighbor mobile computers and less state information is stored into a stable storage in a base station. Hence, communication and storage overhead are reduced. The method is able to be applied to a 3-phase checkpoint protocol without any additional messages. For further reduction of the overhead, not only 1-hop neighbor but also 2-hop neighbor mobile computers are involved into achieving the distributed stable storages. We design a checkpoint protocol by using the proposed method. In simulation evaluation, only 10-20% storage overhead of a naive method storing all state information into a stable storage in a base station is required. Especially in case of sparser mobile computer distribution and higher failure ratio, our extension involving 2-hop neighbor mobile computers works efficiently for reduction of the overhead","PeriodicalId":275012,"journal":{"name":"2006 IFIP International Conference on Wireless and Optical Communications Networks","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121522425","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 : 2006-08-07DOI: 10.1109/WOCN.2006.1666672
A.K. Das, A. Kotal, A. Das
We propose and demonstrate a Mach-Zehnder type electrooptic (EO) modulator with truncated structure of the Y-junctions. The length of the branching zone is reduced to ~3 times in the proposed structure compared with the normal Y-branch structure. The symmetric and asymmetric structures of the junction are studied to consider the fabrication tolerance. We used the simple laser writing process to fabricate the device. The reliabilities of the EO polymer modulators made from the common side-chain polymers were investigated and found guide loss of 0.9 dB/cm in TE mode. The device was hermetically sealed in an inert gas and then found the reduction of Vpi at room temperature was ~7% over 5 weeks operation with 30 mW input power. However, Vpi increases to ~18% when the sample was heated to 50deg;C. The simulated results show the reduction of device length significantly by choice of higher electrooptic coefficient core materials
{"title":"Polymeric electro-optic Mach-Zehnder modulators with truncated Y-junctions","authors":"A.K. Das, A. Kotal, A. Das","doi":"10.1109/WOCN.2006.1666672","DOIUrl":"https://doi.org/10.1109/WOCN.2006.1666672","url":null,"abstract":"We propose and demonstrate a Mach-Zehnder type electrooptic (EO) modulator with truncated structure of the Y-junctions. The length of the branching zone is reduced to ~3 times in the proposed structure compared with the normal Y-branch structure. The symmetric and asymmetric structures of the junction are studied to consider the fabrication tolerance. We used the simple laser writing process to fabricate the device. The reliabilities of the EO polymer modulators made from the common side-chain polymers were investigated and found guide loss of 0.9 dB/cm in TE mode. The device was hermetically sealed in an inert gas and then found the reduction of Vpi at room temperature was ~7% over 5 weeks operation with 30 mW input power. However, Vpi increases to ~18% when the sample was heated to 50deg;C. The simulated results show the reduction of device length significantly by choice of higher electrooptic coefficient core materials","PeriodicalId":275012,"journal":{"name":"2006 IFIP International Conference on Wireless and Optical Communications Networks","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128614058","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 : 2006-08-07DOI: 10.1109/WOCN.2006.1666679
K. Nallaperumal, J. J. Ranjani, S. Christopher, S. Saudia
The popular international standard for compression, the Joint Photographers Expert Group (JPEG) quite often leads to noticeable discontinuities along the boundaries called the `blocking artifacts'. When the image is JPEG compressed the high frequency details of the coded image are mainly contaminated by quantization noise. An estimation of the actual pixel is obtained from the decoded image. The estimated image is denoised using dual tree complex wavelet transform (DTCWT), which is a variant of discrete wavelet transform. This transformation ensures approximate shift invariance and directional selectivity properties that are lacking in the traditional wavelet transform
{"title":"Removal of blocking artifacts in JPEG compressed images using dual tree complex wavelet filters for multimedia on the Web","authors":"K. Nallaperumal, J. J. Ranjani, S. Christopher, S. Saudia","doi":"10.1109/WOCN.2006.1666679","DOIUrl":"https://doi.org/10.1109/WOCN.2006.1666679","url":null,"abstract":"The popular international standard for compression, the Joint Photographers Expert Group (JPEG) quite often leads to noticeable discontinuities along the boundaries called the `blocking artifacts'. When the image is JPEG compressed the high frequency details of the coded image are mainly contaminated by quantization noise. An estimation of the actual pixel is obtained from the decoded image. The estimated image is denoised using dual tree complex wavelet transform (DTCWT), which is a variant of discrete wavelet transform. This transformation ensures approximate shift invariance and directional selectivity properties that are lacking in the traditional wavelet transform","PeriodicalId":275012,"journal":{"name":"2006 IFIP International Conference on Wireless and Optical Communications Networks","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125081823","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 : 2006-08-07DOI: 10.1109/WOCN.2006.1666641
H. Higaki
This paper proposes a novel recovery method, parallel waiting, from a wavelength reservation failure for all-optical networks. Each core router uses a timer and waits for the release of a wavelength if it detects a reservation failure. In addition, forwarding of a reservation request message is not blocked even in case of a reservation failure. Thus, waiting and forwarding are concurrently applied and multiple core routers may wait simultaneously. Based on the parallel waiting recovery, we design a conservative forward waiting (CFW) wavelength reservation protocol
{"title":"Wavelength reservation with parallel waiting in WDM networks","authors":"H. Higaki","doi":"10.1109/WOCN.2006.1666641","DOIUrl":"https://doi.org/10.1109/WOCN.2006.1666641","url":null,"abstract":"This paper proposes a novel recovery method, parallel waiting, from a wavelength reservation failure for all-optical networks. Each core router uses a timer and waits for the release of a wavelength if it detects a reservation failure. In addition, forwarding of a reservation request message is not blocked even in case of a reservation failure. Thus, waiting and forwarding are concurrently applied and multiple core routers may wait simultaneously. Based on the parallel waiting recovery, we design a conservative forward waiting (CFW) wavelength reservation protocol","PeriodicalId":275012,"journal":{"name":"2006 IFIP International Conference on Wireless and Optical Communications Networks","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127433164","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 : 2006-08-07DOI: 10.1109/WOCN.2006.1666594
S. Kumar, S.K. Singh, R. Bhattacharjee
With the increase in need for wireless appliances to support mobility, many schemes have been proposed to improve the quality of service (QoS) levels during handoffs. Although these schemes have been proven to be very effective in improving the latency and packet loss during handoffs to a significant level, they are mainly limited to micro-mobility scenario. In the context of macro-mobility, mobile IP (MIP) still continues to be the major protocol, which is not efficient due to high latency and packet loss. In this paper, we propose a new scheme to handle horizontal handoff in the cases of macro-mobility scenarios. We compare the performance of the proposed scheme with the MIPv6 via simulation in network simulator 2 (ns2) and the results show that the proposed scheme provides significant improvement over MIPv6
{"title":"A new handoff scheme for macro-mobility scenario","authors":"S. Kumar, S.K. Singh, R. Bhattacharjee","doi":"10.1109/WOCN.2006.1666594","DOIUrl":"https://doi.org/10.1109/WOCN.2006.1666594","url":null,"abstract":"With the increase in need for wireless appliances to support mobility, many schemes have been proposed to improve the quality of service (QoS) levels during handoffs. Although these schemes have been proven to be very effective in improving the latency and packet loss during handoffs to a significant level, they are mainly limited to micro-mobility scenario. In the context of macro-mobility, mobile IP (MIP) still continues to be the major protocol, which is not efficient due to high latency and packet loss. In this paper, we propose a new scheme to handle horizontal handoff in the cases of macro-mobility scenarios. We compare the performance of the proposed scheme with the MIPv6 via simulation in network simulator 2 (ns2) and the results show that the proposed scheme provides significant improvement over MIPv6","PeriodicalId":275012,"journal":{"name":"2006 IFIP International Conference on Wireless and Optical Communications Networks","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125366215","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 : 2006-08-07DOI: 10.1109/WOCN.2006.1666634
S. Pandey, D. Singh
In this paper we analyze how radio frequency identification (RFID) technology can be used to efficiently and cost effectively achieve and improve the tracing and tracking in a monitored area network. In particular we describe implementational issues associated to tracing or tracking of any mobile platform (person, robot etc) equipped with a RFID transmitter. We present a `t-monitored area network' model which is more flexible and dynamic and can achieve appropriate location sensing, on the basis of which it would be able to trace the path of a mobile agent in real-time. Our solution works on a standard local area network using a specially designed hardware. Our analysis and practical results are based on actual hardware implementation and promises a very fine granularity in time for consistent location update requests. Our design do not intend to find the exact location coordinates of a RFID tag, which is although acceptable in most of the applications unlike defense where accuracy is crucial, for which our system is modular and flexible enough to allow later modifications as per the specific requirement with some addition or subtraction in the overall cost. Our analysis and practical results indicate that the hardware system designed is low-cost and efficient
{"title":"Efficient and cost effective tracker in monitored area network [t-man] using RFID","authors":"S. Pandey, D. Singh","doi":"10.1109/WOCN.2006.1666634","DOIUrl":"https://doi.org/10.1109/WOCN.2006.1666634","url":null,"abstract":"In this paper we analyze how radio frequency identification (RFID) technology can be used to efficiently and cost effectively achieve and improve the tracing and tracking in a monitored area network. In particular we describe implementational issues associated to tracing or tracking of any mobile platform (person, robot etc) equipped with a RFID transmitter. We present a `t-monitored area network' model which is more flexible and dynamic and can achieve appropriate location sensing, on the basis of which it would be able to trace the path of a mobile agent in real-time. Our solution works on a standard local area network using a specially designed hardware. Our analysis and practical results are based on actual hardware implementation and promises a very fine granularity in time for consistent location update requests. Our design do not intend to find the exact location coordinates of a RFID tag, which is although acceptable in most of the applications unlike defense where accuracy is crucial, for which our system is modular and flexible enough to allow later modifications as per the specific requirement with some addition or subtraction in the overall cost. Our analysis and practical results indicate that the hardware system designed is low-cost and efficient","PeriodicalId":275012,"journal":{"name":"2006 IFIP International Conference on Wireless and Optical Communications Networks","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131081817","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 : 2006-08-07DOI: 10.1109/WOCN.2006.1666569
M. Bhattacharyya, S. Nandi, S. Saha
Authentication and trust management in an adhoc network is a challenging task. Cryptography and other hard approaches do not provide a quantitative measurement of trust. Also, trust assignment to a new node having no history of any previous transaction had not been concrete. Human society authenticates people dynamically. This paper proposes a new strategy involving two parameters alpha and beta, which authenticates a node in a mobile adhoc network drawing inspiration from the way authentication, is done in a human society. The alpha parameter gives the quantitative measurement of seeking trust, and the beta parameter gives the quantitative measurement of assigning trust. The dynamism of trust change in a cluster of nodes is also explained by introducing time credit point, service credit point and discredit point. The strategy proposes to use a downloadable active security component from the trust authentication authority, rather than any passive certificate or encryption based authentication. This paper also says how to choose next trust authority in case the primary authority fails
{"title":"A soft dynamic service specific trust management and authentication scheme for mobile adhoc networks","authors":"M. Bhattacharyya, S. Nandi, S. Saha","doi":"10.1109/WOCN.2006.1666569","DOIUrl":"https://doi.org/10.1109/WOCN.2006.1666569","url":null,"abstract":"Authentication and trust management in an adhoc network is a challenging task. Cryptography and other hard approaches do not provide a quantitative measurement of trust. Also, trust assignment to a new node having no history of any previous transaction had not been concrete. Human society authenticates people dynamically. This paper proposes a new strategy involving two parameters alpha and beta, which authenticates a node in a mobile adhoc network drawing inspiration from the way authentication, is done in a human society. The alpha parameter gives the quantitative measurement of seeking trust, and the beta parameter gives the quantitative measurement of assigning trust. The dynamism of trust change in a cluster of nodes is also explained by introducing time credit point, service credit point and discredit point. The strategy proposes to use a downloadable active security component from the trust authentication authority, rather than any passive certificate or encryption based authentication. This paper also says how to choose next trust authority in case the primary authority fails","PeriodicalId":275012,"journal":{"name":"2006 IFIP International Conference on Wireless and Optical Communications Networks","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131283067","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 : 2006-08-07DOI: 10.1109/WOCN.2006.1666655
G. Loss, M. Diniz, R. Coelho
Contention prediction in photonic packet switched systems is examined in this paper. The signals input distributions were represented by the M/G/infin and fBm processes with different scaling degree, auto-correlation function and heavy-tail distribution. The results demonstrated that rather than the scaling degree or other statistical parameters the signals distribution is a crucial factor to contention. The best photonic packet buffer composition is also investigated to guarantee the video signals performance requirements in terms of mean delay and maximum jitter
{"title":"Contention prediction and evaluation in photonic packet switched systems","authors":"G. Loss, M. Diniz, R. Coelho","doi":"10.1109/WOCN.2006.1666655","DOIUrl":"https://doi.org/10.1109/WOCN.2006.1666655","url":null,"abstract":"Contention prediction in photonic packet switched systems is examined in this paper. The signals input distributions were represented by the M/G/infin and fBm processes with different scaling degree, auto-correlation function and heavy-tail distribution. The results demonstrated that rather than the scaling degree or other statistical parameters the signals distribution is a crucial factor to contention. The best photonic packet buffer composition is also investigated to guarantee the video signals performance requirements in terms of mean delay and maximum jitter","PeriodicalId":275012,"journal":{"name":"2006 IFIP International Conference on Wireless and Optical Communications Networks","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133401147","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 : 2006-08-07DOI: 10.1109/WOCN.2006.1666542
I. Saravanan, G. Sivaradje, P. Dananjayan
The goal of the next-generation all-IP wireless networks is to offer users the capability of achieving pervasive network access with the full support of integrated multimedia services that require various data rates and quality of service (QoS). In such an environment, a single service could be offered at different speeds at different locations/times via separate systems. In order to address resource management and call admission control in cellular/WLAN inter working, a Priority based service interworking architecture with hybrid coupling is presented. The main objective of this paper is to provide better QoS to high-prioritized voice traffic. An effective call admission control strategy is proposed for better QoS provisioning and efficient resource utilization. The results show that the proposed scheme is very efficient in serving voice traffic compared to WLAN-first scheme
{"title":"QoS provisioning for cellular/WLAN interworking","authors":"I. Saravanan, G. Sivaradje, P. Dananjayan","doi":"10.1109/WOCN.2006.1666542","DOIUrl":"https://doi.org/10.1109/WOCN.2006.1666542","url":null,"abstract":"The goal of the next-generation all-IP wireless networks is to offer users the capability of achieving pervasive network access with the full support of integrated multimedia services that require various data rates and quality of service (QoS). In such an environment, a single service could be offered at different speeds at different locations/times via separate systems. In order to address resource management and call admission control in cellular/WLAN inter working, a Priority based service interworking architecture with hybrid coupling is presented. The main objective of this paper is to provide better QoS to high-prioritized voice traffic. An effective call admission control strategy is proposed for better QoS provisioning and efficient resource utilization. The results show that the proposed scheme is very efficient in serving voice traffic compared to WLAN-first scheme","PeriodicalId":275012,"journal":{"name":"2006 IFIP International Conference on Wireless and Optical Communications Networks","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129813351","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 : 2006-08-07DOI: 10.1109/WOCN.2006.1666532
G. Kaosar, A. Mahmoud, T. Sheltami
In this paper we propose a new method of improving the performance of dynamic source routing (DSR) protocol. In DSR, as well as other on-demand routing protocols, every established path is considered as temporary to reflect the mobility effect, therefore, once a path is established, it is associated with an expiration time. After that expiration time the path is deleted from the route cache of the nodes. In practice the mobility of nodes are not equal all the time and we propose to treat paths differently according to their stationary, rather than deleting them after every expiration time to improve performance. By simulation we show that this method improves the performance of DSR
{"title":"Performance improvement of dynamic source routing protocol the mobility effect of nodes in cache management","authors":"G. Kaosar, A. Mahmoud, T. Sheltami","doi":"10.1109/WOCN.2006.1666532","DOIUrl":"https://doi.org/10.1109/WOCN.2006.1666532","url":null,"abstract":"In this paper we propose a new method of improving the performance of dynamic source routing (DSR) protocol. In DSR, as well as other on-demand routing protocols, every established path is considered as temporary to reflect the mobility effect, therefore, once a path is established, it is associated with an expiration time. After that expiration time the path is deleted from the route cache of the nodes. In practice the mobility of nodes are not equal all the time and we propose to treat paths differently according to their stationary, rather than deleting them after every expiration time to improve performance. By simulation we show that this method improves the performance of DSR","PeriodicalId":275012,"journal":{"name":"2006 IFIP International Conference on Wireless and Optical Communications Networks","volume":"85 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115831264","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：