http://hdl.handle.net/2117/1135 Sun, 26 May 2013 09:01:45 GMT 2013-05-26T09:01:45Z webmaster.bupc@upc.edu Universitat Politècnica de Catalunya. Servei de Biblioteques i Documentació no http://hdl.handle.net/2117/16081 Title: Presence-based architecture for wireless sensor networks using publish/subscribe paradigm Authors: García Davis, Ernesto; Calveras Augé, Anna M. Abstract: Ubiquitous communication is a key component of Ambient Intelligence, enabling objects to communicate with each-other by means of a wireless ad-hoc network. A presence service allows knowing the availability or responsiveness status of elements in a communication (entities). Traditionally, only human use this service, however all smart devices or objects (with embedded wireless sensor nodes) could interact with each other thus a presence service could also enhance communication among them. To achieve this objective we look into existing protocols to propose the requirements needed to provide presence service on Wireless Sensor Networks (WSN). The main contribution of this paper is the discussion of requirements for presence services on WSN and the new proposed architecture to cope with presence services in WSN. Mon, 18 Jun 2012 14:39:06 GMT http://hdl.handle.net/2117/16081 2012-06-18T14:39:06Z García Davis, Ernesto; Calveras Augé, Anna M. no Ubiquitous communication is a key component of Ambient Intelligence, enabling objects to communicate with each-other by means of a wireless ad-hoc network. A presence service allows knowing the availability or responsiveness status of elements in a communication (entities). Traditionally, only human use this service, however all smart devices or objects (with embedded wireless sensor nodes) could interact with each other thus a presence service could also enhance communication among them. To achieve this objective we look into existing protocols to propose the requirements needed to provide presence service on Wireless Sensor Networks (WSN). The main contribution of this paper is the discussion of requirements for presence services on WSN and the new proposed architecture to cope with presence services in WSN. http://hdl.handle.net/2117/16080 Title: A presence-aware smart home system (PASH) Authors: García Davis, Ernesto; Calveras Augé, Anna M. Abstract: Wireless Sensor Networks are providing tremendous benefit for a number of industries. A subset of sensed data collected by these networks is presence information. A smart home control system can be designed based on presence information provided by all devices or objects in the home, and we can act depending on it. For this reason, in this paper we present a Presenceaware Smart Home System. We explain its components and features that facilitate the daily living of person’s own home. Mon, 18 Jun 2012 14:29:14 GMT http://hdl.handle.net/2117/16080 2012-06-18T14:29:14Z García Davis, Ernesto; Calveras Augé, Anna M. no Wireless Sensor Networks are providing tremendous benefit for a number of industries. A subset of sensed data collected by these networks is presence information. A smart home control system can be designed based on presence information provided by all devices or objects in the home, and we can act depending on it. For this reason, in this paper we present a Presenceaware Smart Home System. We explain its components and features that facilitate the daily living of person’s own home. http://hdl.handle.net/2117/16008 Title: Optimization of inter-domain presence traffic based on privacy rule sharing: performance and impact on the IMS Authors: Beltrán Martínez, María Victoria; Paradells Aspas, Josep Abstract: Presence information was the key enabler of the great success of instant messaging applications. This information was first limited to simple binary states such as online, offline, or busy. However, it is currently evolving towards a much more generic, flexible concept that includes all context that enables users or applications to adapt and control communications in a more efficient, personalized manner. Presence paves the way for the deployment of advanced communication services and is therefore a key component in Next-Generation Networks. The main barrier to the implantation of next-generation presence-based services is the great amount of traffic involved in the distribution of presence information across domains. In this paper, we give a deep insight into multiple strategies for reducing inter-domain presence traffic. We estimate the capacity demands of these strategies on the IMS servers. Moreover, we enhance two strategies for reducing presence load: Common Subscribe and Federated Common Subscribe. Not only do the proposed enhancements prevent the disclosure of some privacy, they also save presence traffic. Sun, 10 Jun 2012 15:24:39 GMT http://hdl.handle.net/2117/16008 2012-06-10T15:24:39Z Beltrán Martínez, María Victoria; Paradells Aspas, Josep no Presence information was the key enabler of the great success of instant messaging applications. This information was first limited to simple binary states such as online, offline, or busy. However, it is currently evolving towards a much more generic, flexible concept that includes all context that enables users or applications to adapt and control communications in a more efficient, personalized manner. Presence paves the way for the deployment of advanced communication services and is therefore a key component in Next-Generation Networks. The main barrier to the implantation of next-generation presence-based services is the great amount of traffic involved in the distribution of presence information across domains. In this paper, we give a deep insight into multiple strategies for reducing inter-domain presence traffic. We estimate the capacity demands of these strategies on the IMS servers. Moreover, we enhance two strategies for reducing presence load: Common Subscribe and Federated Common Subscribe. Not only do the proposed enhancements prevent the disclosure of some privacy, they also save presence traffic. http://hdl.handle.net/2117/14985 Title: Modeling the maximum throughput of bluetooth low energy in an error-prone link Authors: Gómez Montenegro, Carlos; Seyfettin Demirkol, Ilker; Paradells Aspas, Josep Abstract: We present an analytical model for the maximum throughput of Bluetooth Low Energy (BLE), considering the presence of uncorrelated bit errors and the impact of a key BLE parameter that defines the time between the start of two consecutive connection events. The derived analysis models the generic application of master-to-slave unidirectional data transmission, which also forms an upper bound for bidirectional data transmission throughput. Simulation results show that our model accurately predicts the maximum BLE throughput for all bit error rates and BLE parameter settings evaluated. Mon, 06 Feb 2012 18:49:06 GMT http://hdl.handle.net/2117/14985 2012-02-06T18:49:06Z Gómez Montenegro, Carlos; Seyfettin Demirkol, Ilker; Paradells Aspas, Josep no We present an analytical model for the maximum throughput of Bluetooth Low Energy (BLE), considering the presence of uncorrelated bit errors and the impact of a key BLE parameter that defines the time between the start of two consecutive connection events. The derived analysis models the generic application of master-to-slave unidirectional data transmission, which also forms an upper bound for bidirectional data transmission throughput. Simulation results show that our model accurately predicts the maximum BLE throughput for all bit error rates and BLE parameter settings evaluated. http://hdl.handle.net/2117/14793 Title: Forwarding techniques for IP fragmented packets in a real 6LoWPAN network Authors: Ludovici, Alessandro; Calveras Augé, Anna M.; Casademont Serra, Jordi Abstract: Wireless Sensor Networks (WSNs) are attracting more and more interest since they offer a low-cost solution to the problem of providing a means to deploy large sensor networks in a number of application domains. We believe that a crucial aspect to facilitate WSN diffusion is to make them interoperable with external IP networks. This can be achieved by using the 6LoWPAN protocol stack. 6LoWPAN enables the transmission of IPv6 packets over WSNs based on the IEEE 802.15.4 standard. IPv6 packet size is considerably larger than that of IEEE 802.15.4 data frame. To overcome this problem, 6LoWPAN introduces an adaptation layer between the network and data link layers, allowing IPv6 packets to be adapted to the lower layer constraints. This adaptation layer provides fragmentation and header compression of IP packets. Furthermore, it also can be involved in routing decisions. Depending on which layer is responsible for routing decisions, 6LoWPAN divides routing in two categories: mesh under if the layer concerned is the adaptation layer and route over if it is the network layer. In this paper we analyze different routing solutions (route over, mesh under and enhanced route over) focusing on how they forward fragments. We evaluate their performance in terms of latency and energy consumption when transmitting IP fragmented packets. All the tests have been performed in a real 6LoWPAN implementation. After consideration of the main problems in forwarding of mesh frames in WSN, we propose and analyze a new alternative scheme based on mesh under, which we call controlled mesh under. Wed, 25 Jan 2012 09:54:24 GMT http://hdl.handle.net/2117/14793 2012-01-25T09:54:24Z Ludovici, Alessandro; Calveras Augé, Anna M.; Casademont Serra, Jordi no Wireless Sensor Networks (WSNs) are attracting more and more interest since they offer a low-cost solution to the problem of providing a means to deploy large sensor networks in a number of application domains. We believe that a crucial aspect to facilitate WSN diffusion is to make them interoperable with external IP networks. This can be achieved by using the 6LoWPAN protocol stack. 6LoWPAN enables the transmission of IPv6 packets over WSNs based on the IEEE 802.15.4 standard. IPv6 packet size is considerably larger than that of IEEE 802.15.4 data frame. To overcome this problem, 6LoWPAN introduces an adaptation layer between the network and data link layers, allowing IPv6 packets to be adapted to the lower layer constraints. This adaptation layer provides fragmentation and header compression of IP packets. Furthermore, it also can be involved in routing decisions. Depending on which layer is responsible for routing decisions, 6LoWPAN divides routing in two categories: mesh under if the layer concerned is the adaptation layer and route over if it is the network layer. In this paper we analyze different routing solutions (route over, mesh under and enhanced route over) focusing on how they forward fragments. We evaluate their performance in terms of latency and energy consumption when transmitting IP fragmented packets. All the tests have been performed in a real 6LoWPAN implementation. After consideration of the main problems in forwarding of mesh frames in WSN, we propose and analyze a new alternative scheme based on mesh under, which we call controlled mesh under. http://hdl.handle.net/2117/12123 Title: A study on the influence of transmission errors on WLAN 802.11 MAC performance Authors: López Aguilera, M. Elena; Casademont Serra, Jordi; García Villegas, Eduard Abstract: Since the advent of the first IEEE 802.11 standard for WLANs, several papers have been presented that evaluate the IEEE 802.11 DCF access method. In realistic WLAN environments frame errors usually occur due to non-ideal channel conditions; in this way, papers including adverse transmission conditions in the evaluation have been published later in the literature. In this paper, we review existent analytical models that include the influence of transmission errors in IEEE 802.11 DCF performance. We modify current models and provide a more accurate analysis, thus allowing the evaluation in single rate and multi-rate scenarios with stations subject to different link error conditions. Moreover, this paper exposes the unfairness problem that arises in IEEE 802.11 DCF networks with stations subject to different transmission conditions through analytical and simulation results. Stations are not able to distinguish collisions from failed transmissions due to link errors; both result in a missing ACK and, consequently, the transmitting stations apply the exponential backoff algorithm. This fact leads to a lower performance for stations in worse transmission conditions. Copyright © 2010 JohnWiley & Sons, Ltd. Mon, 28 Mar 2011 18:39:47 GMT http://hdl.handle.net/2117/12123 2011-03-28T18:39:47Z López Aguilera, M. Elena; Casademont Serra, Jordi; García Villegas, Eduard no WLAN IEEE 802.11 MAC Error-prone Since the advent of the first IEEE 802.11 standard for WLANs, several papers have been presented that evaluate the IEEE 802.11 DCF access method. In realistic WLAN environments frame errors usually occur due to non-ideal channel conditions; in this way, papers including adverse transmission conditions in the evaluation have been published later in the literature. In this paper, we review existent analytical models that include the influence of transmission errors in IEEE 802.11 DCF performance. We modify current models and provide a more accurate analysis, thus allowing the evaluation in single rate and multi-rate scenarios with stations subject to different link error conditions. Moreover, this paper exposes the unfairness problem that arises in IEEE 802.11 DCF networks with stations subject to different transmission conditions through analytical and simulation results. Stations are not able to distinguish collisions from failed transmissions due to link errors; both result in a missing ACK and, consequently, the transmitting stations apply the exponential backoff algorithm. This fact leads to a lower performance for stations in worse transmission conditions. Copyright © 2010 JohnWiley & Sons, Ltd. http://hdl.handle.net/2117/11480 Title: Contention- and interference-aware flow-based routing in wireless mesh networks: design and evaluation of a novel routing metric Authors: Catalán Cid, Miguel; Ferrer, Josep Lluís; Gómez Montenegro, Carlos; Paradells Aspas, Josep Abstract: As the popularity of IEEE 802.11-based Wireless Mesh Networks (WMNs) grows, end users of these environments demand better performance and quality of service (QoS). However, the Medium Access Control (MAC) layer of the IEEE 802.11 standard was not initially designed to provide either multihop or QoS capabilities. Therefore, the performance of IEEE 802.11-based WMNs is not optimal. One approach that can mitigate the limitations of IEEE 802.11-based WMNs relies on routing flows through appropriate paths according to: (i) the characteristics of the flows, (ii) the quality of the WMN links, (iii) the contention in transmission, and (iv) the interference in reception. Considerable research effort has been devoted to this topic. However, as we argue in this paper, a comprehensive solution is still needed. This paper presents the Weighted Contention and Interference routing Metric (WCIM). Extensive simulation results show that WCIM outperforms state-of-the-art solutions. Tue, 22 Feb 2011 13:48:01 GMT http://hdl.handle.net/2117/11480 2011-02-22T13:48:01Z Catalán Cid, Miguel; Ferrer, Josep Lluís; Gómez Montenegro, Carlos; Paradells Aspas, Josep no As the popularity of IEEE 802.11-based Wireless Mesh Networks (WMNs) grows, end users of these environments demand better performance and quality of service (QoS). However, the Medium Access Control (MAC) layer of the IEEE 802.11 standard was not initially designed to provide either multihop or QoS capabilities. Therefore, the performance of IEEE 802.11-based WMNs is not optimal. One approach that can mitigate the limitations of IEEE 802.11-based WMNs relies on routing flows through appropriate paths according to: (i) the characteristics of the flows, (ii) the quality of the WMN links, (iii) the contention in transmission, and (iv) the interference in reception. Considerable research effort has been devoted to this topic. However, as we argue in this paper, a comprehensive solution is still needed. This paper presents the Weighted Contention and Interference routing Metric (WCIM). Extensive simulation results show that WCIM outperforms state-of-the-art solutions. http://hdl.handle.net/2117/11120 Title: Deploying large-scale IEEE802.11 networks using IP paging with link-specific capabilities : a standard compliant approach and its performance analysis Authors: Vidal Ferré, Rafael; García Villegas, Eduard; Paradells Aspas, Josep Abstract: IEEE802.11 is a layer two technology that offers limitedmobility support. It suffers from scalability problems caused by the performance of the mechanisms related to the address resolution and the discovery and maintenance of the path information. In this paper, we propose using IP paging with link-specific capabilities to solve this problem. The need of these capabilities is justified showing the limitations of pure-IP solutions when they interact with IEEE802.11 specific functions, mainly the power save mode (PSM). Then, a comprehensive proposal for an IP paging solution that is an extension of the Mobile IPv4 Regional Registration (MIPv4-RR) protocol is presented. Its strengths lie in the fact that there are no interaction problems with PSM, and it is fully compliant with existing IEEE802.11 devices. Finally, in order to show the excellent scalability of our link-specific solution, we carry out an analytical study of its mobility signaling and compare it with the standard MIPv4-RR protocol and IIPP (Integrated IP Paging Protocol), another IP paging solution that does not implement link-specific functions. Thu, 20 Jan 2011 11:34:27 GMT http://hdl.handle.net/2117/11120 2011-01-20T11:34:27Z Vidal Ferré, Rafael; García Villegas, Eduard; Paradells Aspas, Josep no IEEE802.11, PSM, Mobility management, IP paging, Mobile IP, Link-specific IEEE802.11 is a layer two technology that offers limitedmobility support. It suffers from scalability problems caused by the performance of the mechanisms related to the address resolution and the discovery and maintenance of the path information. In this paper, we propose using IP paging with link-specific capabilities to solve this problem. The need of these capabilities is justified showing the limitations of pure-IP solutions when they interact with IEEE802.11 specific functions, mainly the power save mode (PSM). Then, a comprehensive proposal for an IP paging solution that is an extension of the Mobile IPv4 Regional Registration (MIPv4-RR) protocol is presented. Its strengths lie in the fact that there are no interaction problems with PSM, and it is fully compliant with existing IEEE802.11 devices. Finally, in order to show the excellent scalability of our link-specific solution, we carry out an analytical study of its mobility signaling and compare it with the standard MIPv4-RR protocol and IIPP (Integrated IP Paging Protocol), another IP paging solution that does not implement link-specific functions. http://hdl.handle.net/2117/10990 Title: A family of asymptotically good binary fingerprinting codes Authors: Cotrina Navau, Josep; Fernández Muñoz, Marcel Abstract: A fingerprinting code is a set of codewords that are embedded in each copy of a digital object with the purpose of making each copy unique. If the fingerprinting code is c-secure with error, then the decoding of a pirate word created by a coalition of at most c dishonest users, will expose at least one of the guilty parties with probability 1-ϵ. The Boneh-Shaw fingerprinting codes are n-secure codes with ϵB error, where n also denotes the number of authorized users. Unfortunately, the length the Boneh-Shaw codes should be of order O(n3 log(n/ϵB)), which is prohibitive for practical applications. In this paper, we prove that the Boneh-Shaw codes are (c<; n)-secure for lengths of order O(nc2 log(n/ϵB)). Moreover, in this paper it is also shown how to use these codes to construct binary fingerprinting codes of length L=O(c6 log(c/ϵ) log n), with probability of error ϵ<;ϵB and an identification algorithm of complexity poly(log n)=poly(L). These results improve in some aspects the best known schemes and with a much more simple construction. Wed, 12 Jan 2011 17:26:07 GMT http://hdl.handle.net/2117/10990 2011-01-12T17:26:07Z Cotrina Navau, Josep; Fernández Muñoz, Marcel no A fingerprinting code is a set of codewords that are embedded in each copy of a digital object with the purpose of making each copy unique. If the fingerprinting code is c-secure with error, then the decoding of a pirate word created by a coalition of at most c dishonest users, will expose at least one of the guilty parties with probability 1-ϵ. The Boneh-Shaw fingerprinting codes are n-secure codes with ϵB error, where n also denotes the number of authorized users. Unfortunately, the length the Boneh-Shaw codes should be of order O(n3 log(n/ϵB)), which is prohibitive for practical applications. In this paper, we prove that the Boneh-Shaw codes are (c<; n)-secure for lengths of order O(nc2 log(n/ϵB)). Moreover, in this paper it is also shown how to use these codes to construct binary fingerprinting codes of length L=O(c6 log(c/ϵ) log n), with probability of error ϵ<;ϵB and an identification algorithm of complexity poly(log n)=poly(L). These results improve in some aspects the best known schemes and with a much more simple construction. http://hdl.handle.net/2117/10279 Title: La mobilitat a Internet (I Part) Authors: Vidal Ferré, Rafael; Paradells Aspas, Josep; Casademont Serra, Jordi Mon, 15 Nov 2010 10:18:05 GMT http://hdl.handle.net/2117/10279 2010-11-15T10:18:05Z Vidal Ferré, Rafael; Paradells Aspas, Josep; Casademont Serra, Jordi no http://hdl.handle.net/2117/10277 Title: El protocol Mobile IP. La mobilitat a Internet (II Part) Authors: Vidal Ferré, Rafael; Paradells Aspas, Josep; Casademont Serra, Jordi Mon, 15 Nov 2010 10:04:22 GMT http://hdl.handle.net/2117/10277 2010-11-15T10:04:22Z Vidal Ferré, Rafael; Paradells Aspas, Josep; Casademont Serra, Jordi no http://hdl.handle.net/2117/10276 Title: El protocol Mobile IPv6. La mobilitat a Internet (i III Part) Authors: Vidal Ferré, Rafael; Paradells Aspas, Josep; Casademont Serra, Jordi Mon, 15 Nov 2010 09:10:04 GMT http://hdl.handle.net/2117/10276 2010-11-15T09:10:04Z Vidal Ferré, Rafael; Paradells Aspas, Josep; Casademont Serra, Jordi no http://hdl.handle.net/2117/9249 Title: Impact of LQI-based routing metrics on the performance of a one-to-one routing protocol for IEEE 802.15.4 multihop networks Authors: Gómez Montenegro, Carlos; Boix Requesens, Antoni; Paradells Aspas, Josep Fri, 01 Oct 2010 18:32:33 GMT http://hdl.handle.net/2117/9249 2010-10-01T18:32:33Z Gómez Montenegro, Carlos; Boix Requesens, Antoni; Paradells Aspas, Josep no http://hdl.handle.net/2117/7473 Title: Implementation and evaluation of the enhanced header compression (IPHC) for 6LoWPAN Authors: Ludovici, Alessandro; Calveras Augé, Anna M.; Catalán Cid, María Luisa; Gómez Montenegro, Carlos; Paradells Aspas, Josep Abstract: 6LoWPAN defines how to carry IPv6 packets over IEEE 802.15.4 low power wireless or sensor networks. Limited bandwidth, memory and energy resources require a careful application of IPv6 in a LoWPAN. The IEEE 802.15.4 standard defines a maximum frame size of 127 bytes that decreases to 102 bytes considering the header overhead. A further reduction is due to the security, network and transport protocols header overhead that, in case of IPv6 and UDP, leave only 33 bytes for application data. A compression algorithm is necessary in order to reduce the overhead and save space in data payload. This paper describes and compares the proposed IPv6 header compression mechanisms for 6LoWPAN environments. Tue, 01 Jun 2010 15:41:41 GMT http://hdl.handle.net/2117/7473 2010-06-01T15:41:41Z Ludovici, Alessandro; Calveras Augé, Anna M.; Catalán Cid, María Luisa; Gómez Montenegro, Carlos; Paradells Aspas, Josep no 6LoWPAN defines how to carry IPv6 packets over IEEE 802.15.4 low power wireless or sensor networks. Limited bandwidth, memory and energy resources require a careful application of IPv6 in a LoWPAN. The IEEE 802.15.4 standard defines a maximum frame size of 127 bytes that decreases to 102 bytes considering the header overhead. A further reduction is due to the security, network and transport protocols header overhead that, in case of IPv6 and UDP, leave only 33 bytes for application data. A compression algorithm is necessary in order to reduce the overhead and save space in data payload. This paper describes and compares the proposed IPv6 header compression mechanisms for 6LoWPAN environments. http://hdl.handle.net/2117/1437 Title: Wireless technology applied to GIS Authors: Casademont Serra, Jordi; López Aguilera, M. Elena; Paradells Aspas, Josep; Rojas Espinosa, Alfonso; Calveras Augé, Anna M.; Barceló Arroyo, Francisco; Cotrina Navau, Josep Abstract: At present, there is a growing interest in wireless applications, due to the fact that the technology begins to support them at reasonable costs. In this paper, we present the technology currently available for use in wireless environments, focusing on Geographic Information Systems. As an example, we present a newly developed platform for the commercialization of advanced geographical information services for use in portable devices. This platform uses available mobile telephone networks and wireless local area networks, but it is completely scalable to new technologies such as third generation mobile networks. Users access the service using a vector map player that runs on a Personal Digital Assistant with wireless access facilities and a Global Positioning System receiver. Before accessing the information, the player will request authorization from the server and download the requested map from it, if necessary. The platform also includes a system for improving Global Positioning System localization with the Real Time Differential Global Positioning System, which uses short GSM messages as the transmission medium. Tue, 18 Dec 2007 15:09:33 GMT http://hdl.handle.net/2117/1437 2007-12-18T15:09:33Z Casademont Serra, Jordi; López Aguilera, M. Elena; Paradells Aspas, Josep; Rojas Espinosa, Alfonso; Calveras Augé, Anna M.; Barceló Arroyo, Francisco; Cotrina Navau, Josep no PDA, DGPS, E-commerce, IEEE 802.11, GDF At present, there is a growing interest in wireless applications, due to the fact that the technology begins to support them at reasonable costs. In this paper, we present the technology currently available for use in wireless environments, focusing on Geographic Information Systems. As an example, we present a newly developed platform for the commercialization of advanced geographical information services for use in portable devices. This platform uses available mobile telephone networks and wireless local area networks, but it is completely scalable to new technologies such as third generation mobile networks. Users access the service using a vector map player that runs on a Personal Digital Assistant with wireless access facilities and a Global Positioning System receiver. Before accessing the information, the player will request authorization from the server and download the requested map from it, if necessary. The platform also includes a system for improving Global Positioning System localization with the Real Time Differential Global Positioning System, which uses short GSM messages as the transmission medium.