public switched telephone network in computer networks ppt

... efficient adaptive scheduling packets for the uplink traffic in WiMAX networks Abstract In this article, an adaptive scheduling packets algorithm for the uplink traffic in WiMAX networks is proposed ... utilizing the available bandwidth The scheduling is implemented in the SS (uplink traffic) and in the BS (downlink and uplink traffic) However, in this study, it is being addressed the scheduling ... is less complex than the one described in [18] In [19], it was defined an analytical technique for obtaining an optimal polling interval Using this polling interval, the BS should poll the SSs

Ngày tải lên: 20/06/2014, 22:20

... TTI value selective combining and increasing the number of received radio links provides reduction in the transmitted power in-dependently of the combining technique InFigure 8, for the reference ... selective combining (SC) and maxi-mal ratio combining (MRC) 4.1 Selective combining Figure 4shows a scheme of how selective combining oper-ates at the receiver side With SC the path/branch yielding the ... channel P Spreading and scrambling Spreading and scrambling Pilot channel Enhancement information stream Channel coding (turbo code) Rate matching Physical channel segmentation Interleaver Interleaver

Ngày tải lên: 22/06/2014, 22:20

... MINIMIZING QUEUEING DELAYS IN COMPUTER NETWORKS NGIN HOON TONG (B.Eng(Hons.), NUS) A THESIS SUBMITTED FOR THE DEGREE OF DOCTOR OF PHILOSOPHY DEPARTMENT OF ELECTRICAL AND COMPUTER ENGINEERING ... First-Out Generalized Minimum Queueing Delay Generalized Processor Sharing Internet Engineering Task Force Integrated Services JoBS Joint Buffer Management and Scheduling LIRA Location Independent Resource ... Zhang, Minimizing end-to-end delay in high-speed networks with a simple coordinate schedule, Proc. IEEE INFOCOM, Mar 1999. [89] C. Li and E. W. Knightly, Coordinated Multihop Scheduling: A Framework

Ngày tải lên: 17/09/2015, 17:20

... PSTN(Switched Telephone Network)Trong thời đại hiện đại với sự phát triển không ngừng của công nghệ, các hệ thống mạng ngày càng đa dạng và phổ biến Trong lĩnh vực này, PSTN (Public Switched Telephone ... Tài: Tìm hiểu Switched Telephone Network Môn Học: Mạng Máy Tính GIẢNG VIÊN : ThS HOÀNG PHI CƯỜNG LỚP : CS 252 BB SINH VIÊN THỰC : Mã số SV : 27211237294 Họ Tên SV : Trần Đình Minh Kha Đà Nẵng, ... để truyền tải  Tầng 2 - Internet: cung cấp tính năng định tuyến cho dữ liệu từ nguồn đến đích trong các gói tin và thông tin về địa chỉ, di chuyển dữ liệu giữa tầng Link và tầng transport 

Ngày tải lên: 22/05/2024, 15:58

... question underpinning this book in perspective Referring to Figure 1.1, in the beginning of telecommunications, therewere in general two separate networks, one for voice and one for data Eachnetwork ... IP network was different from that of the telephone network, the design philosophy used for the IP network wasalso different from that used for the telephone network First, in the original IP network, ... required in IP networks to provide QoS Itdiscusses packet marking, packet classification, traffic policing and shaping,traffic metering and coloring, Active Queue Management (AQM), andpacket scheduling

Ngày tải lên: 01/06/2014, 12:38

... Maintain indefinitely 17 21 22 13 Maintain until finding other job 1 4 Obtain a permanent position with the State Health Secretary 67 70 55 77 Obtain a permanent position in another public institution ... obtained prior to the beginning of the interview The selection of informants in the qualitative component was purposeful and intentional, aiming to obtain the most relevant information possible for ... positive relation obtained between investment and productivity diminishes the pos-sibility of increasing the investment to improve workers' labour conditions Increasing economic incentives, medi-cal

Ngày tải lên: 18/06/2014, 17:20

... (dij (n)) =  0.1 sin(0.2πn) 0 0 0.01 sin(0.2πn)   7 + sin(0.2πn) 0.1 sin(0.2πn) 0.01 sin(0.2πn)  0 B(n) = (bij (n)) =  0.1 cos(0.2πn) 7 + sin(0.2πn) 0.01 sin(0.2πn) 0 7 + sin(0.2πn)... be relaxed ... http://www.advancesindifferenceequations.com/authors/instructions/ For information about other SpringerOpen publications go to http://www.springeropen.com Advances in Difference Equations © 2012 Huang and Raffoul ; licensee Springer. This ... in continuous-time and discrete-time delayed bidirectional neural networks Physica D 159,... Multiperiodicity of discrete-time delayed neural networks evoked by periodic external inputs

Ngày tải lên: 20/06/2014, 20:20

... that increasing the frequency diversity in the source-to -relay channel results in a more pronounced coding gain than increasing the frequency diversity in the relay- to-destination ... methods In examining the power gain of best relay selection over the other two relaying strategies, we note an interesting trend When the fading channels contain L = 2 taps, the power gain of ... Hermitian, Weyl’s Inequality [29, Theorem 4.3.1] gives λ eff,min ≥ λ sd,min + λ r m d,min . (42) Since l sd,min >0and λ r m d,min > 0 again due to [28, Lemma IV.1], we have l eff,min >0andthus

Ngày tải lên: 20/06/2014, 22:20

... issues to obtain high throughput, as follows: BCO maintains all free slots as a continuous area by constructing each burst in the corner of the available bandwidth area for minimizing external ... Constructing burst in CR j s+1 maintains this burst adja-cent to other constructed bursts In addition, limiting the burst by H j s+1 prevents the horizontal division of the continuous free ... therefore, maintained as a continuous area Thus, by the mathematical induction, the available bandwidth area is always a continuous area 4.2 Burst construction BCO minimizes the internal fragmentation

Ngày tải lên: 20/06/2014, 22:20

... jari.nieminen@aalto.fi Department of Communications and Networking, School of Electrical Engineering, Aalto University, P.O Box 13000, 00076 Aalto, Finland © 2011 Nieminen and Jäntti; licensee Springer ... been studied yet in case of Poisson arrivals and infinite number of users Contention-based multi-channel MAC protocols designed for ad hoc networks can be divided into three main classes, namely ... protocols in ad hoc networks by considering these measures in this paper For this, we derive average access delays and throughputs in closed-form for different multi-channel MAC approaches in case

Ngày tải lên: 20/06/2014, 22:20

... seen in Section III-B.1). 1) Preliminaries: We begin this section by examining two important points. When taking into account multipath fading as well as shadowing as the fading effects in the ... be explained by exam- ining the particular distribution involved, for one sin- gle as well as for multiple interfering cells. A typical cdf of the interference gain (single or multiple inter- ... in Sec- tion IV-B, we obtain the histogram of the interference gain G n (one single interferer) by applying the non-uni - form partitioning generalized inverse method described in III-B.2. Finally,

Ngày tải lên: 21/06/2014, 00:20

... = α · W d i/2in Equation 4 In Figure 8, win-dow-size delegation increases an increasing slope of Wci (x) in an interval of linear to (1 + a)-fold from Wi(x) If we want to control window-size delegation ... maintaining c constant Therefore, we enable the throughput delegation by controlling the number of packets for each STA in the AP sending queue There are a couple of possible ways of controlling ... between throughput andwindow size without window-size delegation Ideally, in the steady state, the congestion window size of STA i Wi(t) changes as the dashed line does in Figure 8 In this case, the

Ngày tải lên: 21/06/2014, 01:20

... Using theorem proving techni-ques, for example, will allow inferring theorems describ-ing the root cause of the incident and steps involved in the attacks Investigating Attacks in Wireless Networks ... attacks in wireless networks, especially in Mobile Ad hoc and Sensor Networks (MASNets) In this article, we propose a formal approach for digital investigation of security attacks in wireless networks ... and point of access Using a formal model of digital investigation in wireless networks should integrate such mobility-based information when modeling actions in the attack scenario Keeping track,

Ngày tải lên: 21/06/2014, 02:20

... two networks to provide a single solution of Internet access for the end users [12,13] The main scenario in this collaborative effort between the two networks is the use of the IEEE 802.16 networks ... and SS integrated device will expedite the market deployment of the interworking of the IEEE 802.11 and the IEEE 802.16 networks 3.2 QoS Mapping in Collaborative IEEE 802.11 and IEEE 802.16 Networks ... optimized resource sharing in this IEEE 802.16/802.11 collaboration In [18], Niyato and Hossain proposed applying game theory to resource allocation in the integrated IEEE 802.16/802.11 network While

Ngày tải lên: 21/06/2014, 11:20

... imization in multi-hop wireless networks in the presence of self interference,” in Proceedings of the 8th International Symposium on Modeling and Optimization in Mobile, Ad Hoc, and Wireless Networks ... are more pronounced in tandem wireless network setups in which the network nodes are located in a linear grid. 1. Introduction The self-interference problem arises in wireless networks when a node ... time slot in the network. Let x s n (t) denote the amount of data of commodity s admitted in the network at node n during time slot t. At the network layer, each node maintains asetofS internal

Ngày tải lên: 21/06/2014, 11:20

... todetermine the time domain and frequency domain spreading domain spreading can be varied by varying the allocated timedomain OVSF code This is in turn modifies the amount offrequency domain spreading, ... new applications increase A challenging issue in supporting QoS in any wireless cellular network is the time-varying channel condi-tions due to various types of fading Employing agile power control ... multiplexing.Frequency domain spreading gives better BER performancewhen the number of users using the same time domaincode is low However, when the number of users using thesame time domain code increases,

Ngày tải lên: 21/06/2014, 11:20

... 4.4 Training Algorithm The classification process basically consists of two phases: training phase and testing phase A training set is used in supervised training to present the proper network ... optimal network size [27] Instead of just adjusting the weights in a network of fixed topology, CCA begins with a minimal network, and then automatically adds new hidden nodes one by one, creating ... the network in order to move the network outputs closer to the targets until the network convergence The training algorithm is mostly defined by the learning rule, that is, the weights update in

Ngày tải lên: 21/06/2014, 16:20

... applying C 3 in the streaming applications under multihop wireless networks. Our C 3 offers a new look into the random linear combi- nation process in conventional network coding. In network coding ... management [22], energy improvement in wireless networks [23], data gossiping [24], as well as data dissemination in sensor networks [11] and in peer-to-peer networks [15]. For storage systems, ... to distributed data in large-scale sensor networks through decentralized erasure codes,” in Proceedings of the 4th International Symposium on Information Processing in Sensor Networks (IPSN ’05),

Ngày tải lên: 21/06/2014, 17:20

... it is of interest to detect any gas leakage To this purpose, one may place a linear sensor network surrounding this area: in the example in Figure 1(a) there are six sensors (In the remainder of ... also been investigated in scenarios with (i) a common binary phenomenon under Trang 2observation and (ii) bandwidth constraints [10] In [11,12],the authors examine the problem of determining edges ... =1 α k P α k |dAP Taking into account the constraint (6), the upper and lower limits of the sum in (10) can be further refined, obtaining the right-hand side expression in (8) The computation

Ngày tải lên: 21/06/2014, 17:20