performance analysis of wireless ad hoc networks

... applications, wireless sensor networks still face a number of challenges due to their particular characteristics that other wireless networks, like cellular networks or mobile ad hoc networks not ... these papers are designed for mobile ad hoc networks but not sensor networks Unlike sensor networks, battery constraint is not a major issue of mobile ad hoc networks Therefore, only few papers ... considerations in wireless ad- hoc sensor networks (WASNs): maximizing the amount of data sent between any pair of all sensor nodes until the first sensor node is out of battery As in sensor networks,

Ngày tải lên: 14/12/2017, 17:47

... Comparison of the Maximal Spatial Throughput of Aloha and CSMA in Wireless Ad- Hoc Networks 9 Comparison of the Maximal Spatial Throughput of Aloha and CSMA in Wireless Ad- Hoc Networks ... Comparison of the Maximal Spatial Throughput of Aloha and CSMA in Wireless Ad- Hoc Networks 19 Comparison of the Maximal Spatial Throughput of Aloha and CSMA in Wireless Ad- Hoc Networks ... Comparison of the Maximal Spatial Throughput of Comparison of the Maximal Spatial Throughput of Aloha and CSMA in Wireless Ad- Hoc Networks Aloha and CSMA in Wireless Ad- Hoc Networks

Ngày tải lên: 14/03/2014, 21:20

... proved also for the case of sparse networks. In this case, R=[0,l ] 2 , and connectivity is investigated for l → ∞  In case of sparse networks, the CTR for connectivity is of the form for some constant ... and some property of the resulting node placement is investigated Example: – length of the longest nearest neighbor link – length of the longest MST edge (CTR) – total cost of the MST  These ... the three goals of: – maximizing network capacity, – reducing contention to access the wireless link – extending network lifetime with respect to the case of no TC  Drawbacks of the COMPOW protocol:

Ngày tải lên: 14/08/2014, 14:20

... subgraph G’ of G which can be used for routing messages between nodes in an energy-efficient way  Why use the routing graph G’ instead of G? – Because G’ is sparse, thus the task of finding routes ... power stretch factor is a measure of the increase in the energy cost due to the fact that we communicate using the routing graph G’ instead of G 5 th ACM MobiHoc – Tokyo, May 24, 2004 Istituto ... two and three- dimensional networks [Blough et al.02a]  In [Blough et al.02a], it is proved that the additional energy cost necessary to obtain a connected backbone of symmetric edges in the

Ngày tải lên: 14/08/2014, 14:20

... efficient broadcast graphs  Similarly to the case of unicast, the concept of broadcast stretch factor of a subgraph G’ of G can be defined  Also in this case, the goal is to find sparse broadcast ... task of finding the energy-optimal broadcast tree rooted at an arbitrary node u of G is NP-hard  [Wieselthier et al.00]: the authors introduce three greedy heuristics for the minimum-power broadcast ... traded off with the cost incurred for making the information available to the nodes. With cost, we mean here either additional HW required on the nodes (e.g., GPS receiver), or message overhead,

Ngày tải lên: 14/08/2014, 14:20

... Optimal value of k for increasing values of n (from [Blough et al. 03]) Remark: setting k = 9 guarantees connectivity w.h.p. for values of n ranging from 50 to 500 5 th ACM MobiHoc – Tokyo, May ... bound on the number of physical neighbors 5 th ACM MobiHoc – Tokyo, May 24, 2004 Istituto di Informatica e Telem atica Mobile networks Mobility: 1/10  Which is the impact of mobility on TC? ... estimation of the number of neighbors might be inaccurate (silent neighbors are not detected); connectivity is not guaranteed  KNeigh [Blough et al.03a]: – Goal: maintain the number of physical

Ngày tải lên: 14/08/2014, 14:20

... 2/11  Ad hoc network model used in this presentation is widely accepted, but it is a very idealized model of a real wireless network  Main limitation of this model: assumption that the radio ... realistic (network and energy) models – More accurate analysis of mobile networks – Considering the effect of multi-hop data traffic 5 th ACM MobiHoc – Tokyo, May 24, 2004 Istituto di Informatica ... MobiHoc – Tokyo, May 24, 2004 Istituto di Informatica e Telem atica Non-homogeneous TC Mobility: 8/10  In case of non-homogeneous TC: more relevant effect of mobility is the message overhead

Ngày tải lên: 14/08/2014, 14:20

... lifetime? – Determination of the optimal frequency for reconfiguration o In general, there is a trade off between the frequency of re-execution of the TC protocol and “quality” of the topology o Open ... 2/16  The protocol is an extension of the COMPOW protocol of [Narayanaswamy et al.02]  The goal of the CLUSTERPOW [KawadiaKumar03] is to overcome a problem of COMPOW: when the node distribution ... how do these energy models impact the performance of TC protocols? 5 th ACM MobiHoc – Tokyo, May 24, 2004 Istituto di Informatica e Telem atica More accurate analysis with mobility Open issues:

Ngày tải lên: 14/08/2014, 14:20

... http://www.uiuc.edu/~kawadia/txpower.html 5 th ACM MobiHoc – Tokyo, May 24, 2004 Istituto di Informatica e Telem atica Technological problems Level-based TC: 6/16  The authors of [KawadiaKumar03] experienced ... hops, with an overall power consumption of 11mW, instead of 100mW 1mW cluster u 100mW 100mW v 10mW 1mW 10mW cluster 100mW cluster n 1 n 2 n 3 5 th ACM MobiHoc – Tokyo, May 24, 2004 Istituto di ... relative advantage in terms of energy efficiency (around 20%) with respect to the level-based version of CBTC, in which p u, ρ is rounded to the next higher power level 5 th ACM MobiHoc – Tokyo,

Ngày tải lên: 14/08/2014, 14:20

... Ad Hoc Networks (2009) 294–306 Contents lists available at ScienceDirect Ad Hoc Networks journal homepage: www.elsevier.com/locate/adhoc Random walk with long jumps for wireless ad hoc networks ... mechanism over ad hoc or sensor wireless networks and many variants of the basic algorithm have been proposed, [19] The aim of these variants is to improve the overall effectiveness of the algorithm ... [1] At each step of RWCðdÞ, instead of selecting 296 R Beraldi / Ad Hoc Networks (2009) 294–306 just one neighbor, the walk moves to the next node after examining a small number d of neighbors sampled

Ngày tải lên: 25/07/2022, 16:05

... of channels N All of the simulation results show that the NP mechanism significantly improves the QoS of SUs with an acceptable QoS degradation of PUs The performance analysis of these two spectrum-sharing ... capacity of secondary users in a cognitive radio network, in Proceedings of IEEE Sarnoff Symposium 2009, New Jersey, USA, 1–5 (March 2009) SM Kannappa, M Saquib, Performance analysis of a cognitive ... probability of PU are evaluated with the steady-state probabilities in CRNs The QoS tradeoff relationships between primary and secondary systems are discussed In addition, the influences of system

Ngày tải lên: 20/06/2014, 22:20

... é ểệ ỉ ẹì ì ễểé í ệ ềỉ Use Markov Decision Process Single-Agent: basic MDP, SMDP, HSMDP Mobile Ad Hoc Network Multi-Agent: DEC-POMDP How to Achieve Stability? How to Control & Optimize? How to ... ì ìì ẵ ìẹẹ ệ ị ì ễỉ ệ Wireless Queueing Model for time-varying channel & topology Assumption: Channel State & Topology State Processes as Irreducible Aperiodic Markov Chain Wireless Queue Scheduling ... Other Contributions: Decentralized Model-free Algorithm, Handle Partial Observability & Locality of Interaction ỉ ểềì ề ỉ ểềá ỉ ểềỉệểéé ểẹ ỉệ èể ỉ ệìỉ ìỉ é ỉí ề ề ề ỉ ệ ỉ ề ế é ỉí ểề ỉ ểệì ỉ...

Ngày tải lên: 14/09/2015, 12:46

... challenges TCP faces in wireless ad hoc networks Section presents a survey of the approaches available to improve the performance of TCP in wireless ad hoc networks and provides taxonomy of these approaches ... TCP in wireless ad hoc networks TCP was designed for wired networks without considering the complexity of wireless networks With the advent of wireless technology TCP was also employed in wireless ... in ad hoc wireless, networks Ad hoc Netw 4, 687–708 (2006) doi:10.1016/j.adhoc.2005.08.001 37 E Hamadani, V Rakocevic, A cross layer solution to address TCP, intra-flow performance degradation...

Ngày tải lên: 21/06/2014, 00:20

... the performance of opportunistic network coding in wireless mobile ad- hoc networks In this thesis we propose to first study and investigate the performance behavior and key control parameters of ... impact of control message on the performance of opportunistic network coding scheme We then use the findings for further study of network coding scheme on large scale wireless ad- hoc networks ... (P2P) file distribution networks to wireless ad- hoc networks, from the improvement of network capacity to increase of network security 1.5 Thesis Organization The rest of this thesis is organized...

Ngày tải lên: 16/10/2015, 11:59

... capacity of wireless networks, ” IEEE Transactions on Information Theory, vol 46, no 2, pp 388–404, 2000 [2] M Grossglauser and D N C Tse, “Mobility increases the capacity of ad hoc wireless networks, ” ... “Delay-limited throughput of ad hoc networks, ” IEEE Transactions on Communications, vol 52, no 11, pp 1957–1968, 2004 [5] N Bansal and Z Liu, “Capacity, delay and mobility in wireless ad- hoc networks, ” in ... constrained ad- hoc networks, ” in Proceedings of the 23rd Conference of the IEEE Communications Society (INFOCOM ’04), vol 1, pp 443–453, Hong Kong, March 2004 [11] H Zhang and J C Hou, “Capacity of wireless...

Ngày tải lên: 22/06/2014, 00:20

... local topological status of the wireless ad hoc network To a certain extent, the node locations and their corresponding degrees would affect the configuration of the wireless ad hoc network and even ... with that of the simulation NETWORK CAPACITY As mentioned above, the max-flow capacity is another important parameter on the performance of network However, in the case of wireless ad hoc networks, ... Letaief, “On the geometrical characteristic of wireless ad hoc networks and its application in network performance analysis, ” to appear in IEEE Transactions on Wireless Communications [6] J Orriss and...

Ngày tải lên: 22/06/2014, 22:20

... protocol for improving TCP performance on multihop wireless ad hoc networks, ” in Proceedings of the 7th International Symposium on Modeling Analysis and Simulation of Wireless and Mobile Systems ... problem in 802.11-based wireless ad hoc networks was first reported in [1], and it was further investigated in [2] The TCP unfairness problem in multihop wireless ad hoc networks was reported in ... source routing in ad hoc wireless networks, ” in Mobile Computing, chapter 5, pp 153–181, Kluwer Academic, Norwell, Mass, USA, 1996 R K Jain, The Art of Computer Systems Performance Analysis, John...

Ngày tải lên: 22/06/2014, 22:20

... dynamic nature of data flows in a network 17 2.1.1 Robustness in wireless ad hoc networks In recent years, a number of routing protocols have been designed for wireless ad hoc networks Many routing ... wireless networks are also very useful for wireless ad hoc networks, so we will also include them in the investigation 2.1.1.1 Routing Structure Generally, routing structure for wireless ad hoc ... connections to wireless ones Yet these advances are based on infrastructural topologies where all wireless terminals connect to a single gateway A wireless ad hoc network is a collection of wireless...

Ngày tải lên: 09/09/2015, 11:24

... SECURITY FOR WIRELESS AD HOC NETWORKS Farooq Anjum and Petros Mouchtaris SECURITY FOR WIRELESS AD HOC NETWORKS SECURITY FOR WIRELESS AD HOC NETWORKS Farooq Anjum and Petros ... managing the security of the network Such solutions are not applicable for wireless ad hoc networks on account of the features of these networks The increased vulnerabilities of ad hoc networks and the ... system administration, and physical security Without adequate security, enterprises will shy away from the use of wireless ad hoc networks, governmental agencies will ban the use of wireless ad hoc...

Ngày tải lên: 25/03/2014, 12:07

... throughput performance is compared for increasing number of source nodes in the ad hoc network All the nodes are randomly placed in a radius of 200 m Concurrent transmissions always lead to collisions ... are worth mentioning when ad hoc network operates under heavy load and fast fading conditions: (1) A particular relay may not be reachable due to fading condition or out of coverage range, and (2) ... rate as a function of SNR A Overview of IEEE 802.11 protocol Figure Cooperative ad hoc network illustration and 11 Mbps [10] It uses direct sequence spread spectrum at a frequency of 2.4 GHz in Industrial,...

Ngày tải lên: 21/06/2014, 03:20