Computer and Network Technology

The following sections are included:

• Organizing Committee

• Technical Committee

• Preface

• Contents

In recent years, the two-factor model has been improved in many papers. In this paper, we consider two new factors and build a new consider SIQR model for Internet worm virus propagation. By using theory of differential equations, the dynamical property of the model is analyzed and the regularity of Internet worm virus propagation is gained. In the end, the numerical simulation is presented.

Designing of a secure routing protocol is a challenging issue in mobile ad-hoc network (MANET) because of the lack of trusted centralized authority, easy eavesdropping, dynamic network topology and limited resources. The false alarm raised during malicious node detection prevents the genuine nodes, from their normal activities. If an adversary could succeed on generating false alarm and therefore isolates a number of nodes from the network which leads to a DoS attack. This paper proposes a defense mechanism called SABAD, against black-hole attacks on AODV protocol in MANET. SABAD considers all the major factors contributing for packet dropping to reduce false-alarm during black-hole node detection.

To reduce the cost of routing devices and to improve network performances for both wired and wireless packet networks, this paper proposes the Link Interface Code (LIC) based forwarding, which can achieve fast flexible switching with scalability, simplicity, security and enhancement of the network QoS ability. LIC-based forwarding uses the LIC to route and forward the data packet in each router. It executes like the explicit route by establishing the connection-oriented LIC path in advance and it can run on existing routing protocols. We design two types of codes for the LIC-based forwarding, the One-way connection-based LIC (OLIC) and the Two-way connection-based LIC (TLIC). The OLIC just contains route information from a send to its receiver and the TLIC contains both the route information from the send to its receiver and the route information from the receiver to its sender. Compared with OLIC, TLIC is more suitable for interactive real-time applications. Experiment result shows that LIC-based forwarding achieves lower end-to-end delay than MPLS does and it can provide flexible fast forwarding.

In the context of modern man constantly moving from place to place there is a need for a mechanism which gives mobile user the necessary information about the new location. The scope of the present work is to simulate the use of "Push Technology" for the purposes of efficient location-oriented data transfer to the user. Push technology stems from a very simple idea. Rather than requiring system to explicitly request (i.e., "pull") the information that they need, data can be sent to users without having them specifically ask for it. The advantages of 'push' are straightforward. The traditional 'pull' approach requires that users know a priori where and when to look for data or that they spend an inordinate amount of time polling known sites for updates and/or hunting on the network for relevant sites. Push relieves the user of these burdens. The paper also proposes a location tracking method which predicts the users futures movement based on the information of the past movements of the user. This prediction system can allocate the resources to the most probable cell with the instead of allocating excessive resources blindly to the neighboring cells of the user. Further, the paper recommends a filtering mechanism, which avoids the unwanted data to be sent to the user by the server. Agent based mechanism is used in this paper to do the necessary filtering of data.

This paper investigates the speed response characteristics of the internal model controller. Speed response parameter of the internal model controller is adjusted from low value to high value. The different value speed response is plotted using Matlab/Simulink. Chirp noise is added in the plant and the dynamic behavior is studied, sinusoidal dither signal is injected and the suppression of limit cycle oscillation is proof read and the performance is presented.

Ready and secure communication between multitude of devices (tags, tag-readers, databases) employing RFID networks is paramount to increase RFID adoption. In addition, the ability to change (and even share) ownership of these devices is equally important, keeping in mind privacy issues. Given the low level of technology available in tags, it is necessary to keep these communications simple and lightweight, yet have the necessary cryptography built in. In this paper, we propose a light-weight protocol that meets these requirements, and use it for sharing ownership. This protocol does not rely on a Trusted Third Party, does not involve any key transfers between owners, and uses lightweight cryptographic techniques. Thus it is easily implementable, even in the most basic tags. We also perform necessary security analysis to ensure that this protocol is accurate, maintains confidentiality and provides forward security.

IEEE 802.11 WLANs (Wireless Local Area Networks) have become synonymous as one of the main access technologies to the internet almost everywhere including business, office and home. This paper develops a simple queuing model to analyze the performance of IEEE 802.11 WLANs. We model a single IEEE 802.11 Wireless Station (WSTA) by means of a single server queue with infinite buffer wherein the service time is a function of backoff process which is function of number of stations trying to compete in the medium along with retry limit. We first derive the mean and second moment of backoff time of a WSTA using the Markov Chain Model outlined in [2]. Then the service time distribution is obtained. Then different distributions for the arrival process - Poisson, deterministic, normal and Pareto, are considered to model traffic realistically and analyze the waiting time and the queue length in the GI/G/1 queues for different network sizes.

Localization in wireless network refers to determining the location of a mobile user which may either be stationary or in motion. This paper presents the design and evaluation of an algorithm for localization of mobile nodes in GSM networks. The proposed algorithm does not use GPS and has the advantages of being cost effective and reliable. The received signal strength from the base stations in the proximity of the mobile form the basis for the proposed algorithm. The algorithm concentrates on improving the accuracy of estimated location of the mobile by using a prediction-interpolation technique. The key aspects of the proposed localization technique are that it assumes linear dependency between the accuracy of the estimated mobile location and the received signal strengths from the neighboring base stations, and tunes the location estimate based on this mapping.

In wireless mobile ad hoc networks, nodes change their topology very frequently and unpredictably over time. In such environment, routing protocol needs to update neighbor information very frequently. Many routing protocols suggest that each node should periodically broadcast HELLO packet to their direct neighbors. In these protocols, if node does not receive HELLO packet till HELLO expired time, it deletes the entry of that neighbor from its neighbor table or routing table. This paper presents a metric which mitigates the problems due to higher value of this HELLO expired time. We also incorporate this metric in greedy routing decision of geographical protocols. Performance evaluation of greedy routing and proposed greedy routing is through NS simulation. Simulations show that our proposed greedy routing outperforms existing greedy routing with respect to packet delivery, throughput and overheads.

In P2P computing, peers dynamically organize themselves to support knowledge sharing and collaboration. The dynamic and decentralized nature of P2P systems causes the issues of maintaining security and trust between peers to become critical. Establishing trust among anonymous peers is a challenging task. This paper discusses a Role Based Trust model for building credential graphs. Loops in the directed graph may lead to cyclic dependency problem causing deadlock in the trust computations. We propose using the DFS algorithm, to convert the graph into a tree to avoid the cyclic dependency problem. The resulting credential tree can be used for trust computation and delegation.

The recent development in the field of telecommunication technology and the popularity of the internet have caused the changes in the field of communication, which moves towards to new innovative communication through IP networks like IP telephony. Therefore, IP Telephony requires the support of guaranteed quality of services and charging to provide service for potential customers, which makes some significant changes in the billing network model of telecommunication. The billing model support different level of services in terms of quality and charging requirement made by the users and would be the most efficient in terms of prices to be paid. This paper suggests a methodology to resolve the specific problem of internetworking between IP and PSTN networks for supporting quality voice calls to make true charging. The main objective of the paper is to propose the internetworking interface function (IIF) with the charging and billing methods over the IP telephony and PSTN networks.

Multicast provides a more efficient routing strategy for multimedia applications in mobile environments with large numbers of simultaneous receivers. Many multicast routing protocols of MANET operates in an On-Demand basis. Multicast Routing Protocol relies on periodic, network-wide flooding for route discovery and maintenance. While forwarding the packets the Packet Delivery Ratio (PDR) is a critical metric to be considered. Many methods were proposed to improve PDR which in turn will improve the reliability of transmission in MANET. By handling request (JOIN-QUERY) and reply (JOIN-REPLY) phases in an opportunistic way, the intermediate node's forwarding mode can be changed. This paper proposes algorithms to improve PDR and power consumption of the nodes in an optimal fashion. The results obtained confirmed that a medium network of size 20 to 50 can give best performance by following the proposed algorithms.

Rosenbloom and Tsfasman introduced a new metric (RT metric) which is a generalization of the Hamming metric. In this paper we propose a Cayley interconnection network based on the RT metric. We also introduce a new family of Cayley graphs on symmetric groups with respect to the RT metric. We also describe various algebraic and topological properties of these networks and propose optimal routing algorithm.

In the modern simulation training, networking simulation must be situated on its' appropriate important position. To solve the problem of networking process simulation in the simulation training systems, related works were firstly introduced and the deficiency analysis of the framework of traditional simulation training systems was also provided. Then the framework of separated mode and embed mode based on networking simulation were analyzed in detail. On the basis of this, a distributed embed networking simulation training system framework and the realization strategy of the networking simulation proxy node were brought out. The research provides new idea and available solution for taking the battlefield communication network environment effect into account in simulation training system.

Service discovery is an integral part of constructing self-configuring Mobile Ad Hoc Networks (MANETs). By combining service and route discovery, both the identity of the node providing the service and the route to the service are discovered at once. This approach differs from related work on service discovery in ad hoc networks, which perform service discovery only at the application layer without discovering a route to the service. The idea of adding service discovery to reactive routing protocols for MANET was earlier proposed in an Internet-Draft using AODV as the routing protocol. In this paper, we propose modifications and extensions to the Internet-Draft. This paper presents the performance evaluation of Reactive routing protocols (AODV and DSR) for service discovery.

Internet environment faces a lot of vulnerability at the present situation. The pervasive and ubiquitous nature of the internet coupled with growing concerns about cyber terrorism demand immediate solutions for securing the internet infrastructure. In these Routing table poisoning is more pronounced. So far the solutions for these attacks are the Intrusion detection. Using an attack analyzer in the fast moving internet environment is not scalable solution. More over it causes failure of the network or heavy loss to the network which is later detected by the attack analyzer based on some criteria and then the network is notified about the attack. So I suggest an alternate for this solution, i.e., a Protocol driven solution for the routing table poisoning attack. In this the router security is enables by the cryptographic techniques, sharing and managing of a public key among the routers. Then the routing table updates are done with certain rules that are enforced by the protocol.

In a regular fashion, industries and businesses have been highly related to data mining, in such a manner that they are ready to expend a great deal of money for solving their problems, since user can not easily take advantage of data mining in their businesses. The goal of the present study is to investigate the basis of data mining formation in order to understand some semi-automatic parts being created in the past to solve the problems. Therefore, we put stress upon general data mining model from the beginning and expand our procedure through details and shapes of basic storage form, intermediate user functions model, as well as its applicability which make easy the related theory and accompanying procedures. Hence, we take advantage of different choices and expenditure routines in order to lessen and shorten the procedure immediately.

This paper presents high-performance and compact architecture for single round Advance Encryption Standard (AES) security algorithm using feedback mode. Two design based on stated architecture has been implemented on virtex-4 Field Programming Gate Array (FPGA) device. These two designs differ in method used for sub-bytes function implementation, in first design Look-Up Tables (LUTs) and in second design fully combinational gates using Composite Field Arithmetic (CFA) has been employed for sub-byte function implementation. Fair performance comparison of these two designs with each other and with other well known previous claims has also been presented. Finally, LUTs based and CFA based designs are achieved with encryption rate and number of Configurable logic blocks (CLBs) slices 1.0497 Gbps/2571 and 880.81 Mbps/1668 respectively. These results are among the fastest hardware implementations with better area utilization.

Short Message Service (SMS) is increasingly being adopted and utilized in banking industry. However SMS does not guarantee confidentiality and integrity of message content, it was specifically intended for sending non-sensitive information in a GSM network. In the mobile communication systems, security offered by the network operator only applies on the wireless link; data delivered through the mobile core network may not be secured enough. Therefore end-to-end security mechanisms are required. The existing end-to-end security mechanisms are provided at application level and typically based on public key cryptosystem. The main concern in a public-key setting is the authenticity of the public key; this issue can be resolved by identity-based (ID-based) cryptography where the public key of a user can be derived from public information that uniquely identifies the user. This paper presents an encryption mechanism based on the ID-based scheme using Elliptic curves to provide end-to-end security for delivery of SMS-banking services. This mechanism has been implemented over the standard SMS network architecture and the Performance analysis showed that the encryption speed on the mobile device is faster than the duration of the transmission.

Electrostatic precipitator is an advantageous choice for air cleansing and pollution control. Volumes of industrial dust, fly ash, fumes and mist particulates are easily collected and the air cleaned through their use. The paper introduces the application of automatic monitoring system for electrostatic precipitator in a steel plant. In order to improve the automation level of electrostatic precipitator, to reduce administrative personnel's labor intensity and arrive the energy conservation goal, the automatic monitoring system for electrostatic precipitator is provided which is based on ifix configuration software. The implement of the system will monitor how electrostatic precipitator works. Considering reducing the energy, it adopts turbidity close-loop control strategy and the method of online detecting removal efficiency. Its function includes detection, display, control, protection, alarming and management. It can storage the running parameters and the information about what the operators do to the database. The system has provided fast, accurate, the comprehensive information basis for the operator about the monitoring and the maintenance. It has realized the electrostatic precipitators long-distance monitoring and the automated management goal.

Key establishment and management is the heart of secure communication. Most key pre-distribution schemes for mobile sensor networks assume that there is no fixed infrastructure available to mobile sensor nodes. Applications of sensor networks are increasing in civil area where fixed infrastructure facility is available to sensor nodes. Proposed scheme of key establishment and management can be used in situation where fixed infrastructure is available to mobile sensor nodes. Proposed scheme exhibits noteworthy properties like node authentication, resilience and connectivity.

While transferring electronic patient report (EPR) data along with corresponding medical images over network, confidentiality must be assured. This can be achieved by embedding EPR data in corresponding medical image itself. But checking the integrity of this embedded data must be needed so to assure that retrieved EPR data is original and not manipulated by different types of attacks. This paper proposes checking the integrity of EPR while hiding the data bits in Discrete Cosine Transform (DCT) domain.

High imperceptibility is achieved by adaptively selecting the efficient DCT blocks. Even a slight modification of stego image in embedded region as well as in ROI (Region of Interest) can be detected at receiver so to confirm that attack has been done. The embedding scheme also takes care of ROI which is diagnostically important part of the medical images and generates security key automatically.

IEEE 802.16e standard for 4G Cellular Technology-Mobile WiMAX is proposed to support mobility. As a result, handover has become one of the most important QoS factors. Because of lack of clarification in the conventional algorithm for handover process, there exists wastage of channel resource along with undesired delay. Again, it causes significant degradation in the overall system performance. Existing standard for handover includes scanning as one of the most vital processes. But scanning requests without proper response and delayed initiation of scanning only deteriorates the scenario. In this paper, a modification of the scheduling process of scanning is proposed to reduce redundant scanning requests and overall handover operation delay.

The Hybrid Optical Packet Network (HOPnet) is a kind of high-speed network with the development of optical network. The traditional TCP transport protocol performs poorly in this kind of environment. This paper investigates the characters of HOPnet and the issues of TCP performance over HOPnet. A negative acknowledgement scheme, namely selective negative acknowledgement (SNACK), is applied to TCP over HOPnet and a series of NS-2 simulations are performed to compare its performance with the standard TCP. The simulation results confirm that the SNACK scheme outperforms the conventional TCP scheme in HOPnet.

The dynamic topological change in mobile ad hoc networks hinders the possibility of predicting the behavior under different communication and data transfer requirements. In this paper, a detailed analysis and interpretation was made by simulating the network with DSR protocol, specifically for streaming multimedia applications, under different scenarios set by varying the pause time, workload and data rate. The effect of these variables is evaluated in terms of average throughput, average end-to-end delay and average jitter. It is evident from the analysis that the performance of the DSR protocol is superior under medium mobility compared to high and low mobility scenarios. The influence of workload and data rate on the performance metrics under low, medium and high mobility scenarios were also discussed.

Broadband wireless access networks, such as the IEEE 802.16e standard for wireless metropolitan area networks (WMANs), aim to provide high bandwidth, low-cost and scalable solutions that extend multimedia services from backbone networks to mobile users. Handover is one of the most critical components in mobility management and its related latency plays an operative role in performance of mobile WiMAX environment. By cooperation of MAC and DP Layers, the overall handover latency in IEEE 802.16e networks would be reduced. In this paper, we propose a fast and seamless handover scheme in mobile WiMAX networks that uses the cross-layering design model to create a new interface between layers and improve the quality of services regarding to the real-time multimedia applications demand.

The paper comprehensively explains the vital role of swarm intelligence in network centric warfare. It describes the various types of existing NCW swarms and proposes some new forms of this strategy to improve the efficiency of such critical environments. To accomplish this goal, the paper presents the NCW swarm taxonomy including different types of this strategy such as human swarm, swarm robots, sensor swarm, service swarms and swarm coordinating strategies together with their formation process in NCW related areas. We also take a look at the existing tools and infrastructures to implement these technologies in such heterogeneous environments.

Wireless Mesh Networks (WMNs) are recently gaining much attention due to the scope for increasing aggregate network throughput by utilization of non-overlapping channels. In this context, Channel Assignment (CA) is a key issue in offering optimal performance multi-radio multi-channel WMNs. A good CA scheme can maximize number of simultaneous transmissions, which in turn maximizes aggregate network throughput. In this paper we address key issues in designing CA Algorithms for multi-channel multi-hop networks. We classify various state-of-the-art Channel Assignment Schemes and present a comparative analysis. Some future research directions for CA are also suggested.

Steganographic techniques are being applied across a broad set of different digital technologies. The steganographic method will be used for internet/network security, watermarking and so on. So, the steganography is the process of hiding one medium of communication (Text, Sound, and Image) within another. It can work on JPEG 2000 compressed images & Stir Mark images.

The 'Steganalysis' is the field of detecting the covert messages. Almost all steganalysis consist of hand-crafted tests or human visual inspection to detect whether a file contains a message hidden by a specific steganography algorithm.

The new method of steganalysis based on neural network to get the statistics features of images to identify the underlying hidden data. We first extract the features of image embedded information, then input them into neural network to get the output. Experiment result indicates this method is valid in 'Steganalysis'

The neural network in still images is used to overcome the hurdles by hiding the data indirectly into graphical image using neural network algorithm to get cipher bits, The generated cipher bits are then placed in the least significant bit position of the carrier image. The XOR propagation network model is used which acts as a multilayer perceptron.

Speech enhancement from the mixture of blind sources has been a challenge for many researchers for almost three decades. Blind source separation (BSS) is an emerging technique, which enables the extraction of target speech from observed mixed speech signals. In order to enhance the quality and intelligibility of speech it can be assumed that the original speech signal and the noise signal are mutually independent. BSS algorithms are based on restoring the statistical independence of the source signals. This paper is concerned with blind source separation of mixtures of acoustic signals, especially speech in which the source signals are instantaneously mixed in unknown nonlinear processes. A statistical and computational technique, called independent component analysis (ICA), used for BSS. Speech enhancement is done by according to the Entropy Maximization theory for minimizing the mutual information. By using real speech signals, the entropy of the power spectrum of the extracted unmixed signal is maximized, corresponding change in weights for the feedback loop is find out. The cross power spectral density and cross correlation coefficient of observed unmixed signal and test signal is check to conform the received signal is the original signal. The model is verified and compared with the existing algorithms on the basis of signal to noise ratio. Simulation results demonstrate that the proposed new algorithm has good Performance in speech enhancement.

Designing a secret key algorithm needs high-level security against all kinds of unauthorized attacks like active and passive attacks. Here we have introduced a new block cipher algorithm named Multi Operator and Delimiter based Data Encryption Standard (MODDES). It is an unique independent approach, which uses the concept of stack of operators and randomized delimiters selection along with some suitable mathematical logic and lookup table concept as well. Thus a new protocol has been designed to encrypt a given text, which allows a high-level security and higher throughput. The algorithm is implemented and is successfully tested on text file as well as corresponding digital text file for image, audio signals as well.

While designing an encryption algorithm, apart from security, one of the most important parameter that are required to be considered is it's performance and cost analysis. Here we have tried to highlight the performance of some well known data encryption algorithms like DES, 3DES, AES ( Rijndael ) and compare them with the MODDES. Based on the experiment, it can be said that the MODDES algorithm is one of the best performing partially symmetric key algorithm among the algorithms chosen for implementation, particularly for the text message with limited size.

This paper presents a high level implementation of a high performance FFT for Ultra Wide Band (UWB) applications. The design has been coded in VHDL and targeted into Xilinx Virtex-E XCV400E FPGAs. The hardware requirement comparison shows that our implementation outperforms other implementations of FFT on the same series of FPGAs. Radix-2² algorithm has the same multiplicative complexity as the Radix-4 algorithm, but retains the butterfly structure of Radix-2 algorithm. The design is parameterizable in terms of input word length, output word length, twiddle factor word length, and processing word length. Also, it is scalable in terms of number of stages.

The key exchange protocols using passwords achieved great attention due to its simplicity and efficiency. On the other hand, the protocol should resist all types of password guessing attacks, since the password is of low entropy. Recently Chang and Chang proposed a novel three party simple key exchange protocol. They claimed the protocol is secure, efficient and secure. Unless their claims Yoon and Yoo presented an Undetectable online password guessing attack on the above protocol. In the present paper we demonstrated an another attack called as a key recovery attack on Chang and Chang protocol using the Undetectable online password guessing attack proposed by Yoon and Yon. Further we discussed the efficient methods of computing the ephemeral keys, when the password of one party is exposed.

The allocation of bandwidth and other network resources for VBR Video traffic is a challenging task due to bursty nature of traffic as well as rigid Quality of Service requirements of applications. In this paper, we propose prediction based approach for efficient bandwidth allocation for multimedia applications. In this we demonstrate frame level and GOP level prediction of traffic using MLP networks (Multi Layer Perceptron). D-Bind Model [12] is used for the computation of resource requirements which can be used for resource reservation. Video Traffic Prediction plays an important role to achieve desired QoS, overall network utilization and in determining dynamic resource requirements. We have extensively studied traffic prediction at frame and GOP levels. We show that neural network traffic predictor can successfully predict real-world VBR video traffic, thereby enabling predictive dynamic bandwidth control and allocation. Neural Network Traffic Prediction with D-Bind Model works well with various dynamic bandwidth allocation schemes.

It happens many times! A user tries to log into a corporate network but fails to remember his or her Windows password when prompted and is locked out of everything. Lock outs have cost associated with it because the user can't work and has to call the company's helpdesk to reset the password. As much as 30 percent of all helpdesk calls are password-reset requests, on average every request takes 20 minutes to resolve and costs more than $23 on helpdesk operations alone, says market research firm- Gartner.' Advanced Authentication and Password Reset Manager eliminates those minutes and dollars too. It provides self-service to users to reset their passwords on their own in few minutes even before login to the system. Advanced Authentication and Password Reset Manager should automate the process of resetting passwords. This will reduce the help desk calls and hence will increase the productivity and reduce the cost. THE ULTIMATE GOAL - Lower cost and higher productivity

Wireless MESH network is a new pattern that allows the enhancement of existing wireless Network with multi hop connection. The medium for transmission of wireless network is air, which is unprotected medium therefore the challenging problem facing by wireless network is network security, some of network security problems such as eavesdropping of the wireless signal, jamming of the wireless channels, network intrusions. Here we are focusing on network intrusions detection. Intrusion is used to describe attacks from the outside hence intrusion detection is detection of outside attacks. We are using game theory, a study of how to mathematically determine the best strategy for given conditions in order to optimize the outcome for detecting intrusion in wireless mesh network. We represent the interaction between intruder and intrusion detection system (IDS) as the 2 × 2 signaling game which comes under non-cooperative game with incomplete information where one player is informed player i.e. intruder and other is uninformed player i.e. IDS, who is unaware of intruder source.

Today, the design of test case with enhanced reliability is a real challenge as it needs expert designers with perfect knowledge about the whole system and also the traditional test case generation approach faces a challenge in test results analysis, because of the difference between the generated test cases and the expected results. So, it will be better if we could establish a method for automatic test case generation based on both program structures and the functional requirements in specifications. Mining approach can be used to have a perfect knowledge about the whole system. This paper presents a novel approach of mining test cases.

This paper investigates the suitability of various techniques to model efficient intrusion detection systems. We briefly describe some of the latest developments made to increase the efficiency and accuracy of intrusion detection using support vector machines(SVMs), artificial neural networks (ANNs) and linear genetic programming (LGP). One approach focuses on reducing training time of SVMs using clustering tree analysis called CT-SVM. Another approach called DT-SVM combines Decision tree and SVM to maximize the detection accuracy. Third uses LGP with feature selection and ranking algorithm. Fourth uses ANN with Back propagation Algorithm. Here we will compare the performances of all the above approaches.

Future wireless communication requires the design of a single wireless user terminal able to autonomously operate in different heterogeneous access networks. A large number of reconfigurable hardware architectures have been proposed both in academia and commercially for the efficient realization of wireless multimedia communication systems. A reconfigurable architecture has evolved from fine-grained to coarse-grained architecture due to some major advantages such as efficient area, high performance and low power. There are several shortcomings for the existing reconfigurable architectures. This paper gives a brief survey of coarse-grained reconfigurable architectures used for multimedia and wireless communications. It is also found that applying agent-based model into a suitable reconfigurable architecture, the overall system flexibility and efficiency will be significantly improved.

The concept of optical burst switching (OBS) aims to allow access to optical bandwidth in dense wavelength division multiplexed (DWDM) networks at fractions of the optical line rate to improve bandwidth utilization efficiency. This project gives an alternative network architecture combining OBS with dynamic wavelength allocation under fast circuit switching to provide a scalable optical architecture with a guaranteed QOS in the presence of dynamic and burst traffic loads. It is assumed that there are no buffers or wavelength conversion in core nodes and that fast tunable laser sources are used in the edge routers. Based on an analytical model, upper bounds for these parameters are derived to quantify the advantages of wavelength channel reuse, including the influence of the signaling round-trip time required for light path reservation. The results allow to quantify the operational gain achievable with fast wavelength switching compared to quasistatic wavelength-routed optical networks and can be applied to the design of future optical network architectures.

AntNet¹ is one of the approaches to adaptive learning of routing tables in wide are best-effort datagram networks. The AntNet algorithm, as proposed by Di Caro and Dorigo is resource intensive algorithm. In this algorithm two types of ants are generated viz. Forward ant and Backward ants. While traveling from a source to a destination the forward ants store their paths and of traffic conditions they encounter. After reaching the destination the forward ant transfers its memory to the backward ant and dies. The backward ant retraces the path traversed by the forward ant and updates the routing tables in the path. Since the mobile adhoc networks are dynamic and every effort should be made to reduce the resource intensity. We have made an effort to reduce the resource intensity in the basic AntNet algorithm. We propose three methods. The first method experiments with not generating a backward ant for every forward ant, instead we collect a set of forward ants and generate a subset of backward ants by choosing the best trip times among the received forward ants. In the second method we update the routing tables with the help of forward ants without generating backward ants. In the third method we update the routing table only at the destination node. Since every node is a destination for all other nodes, routing table at every node gets updated. In this method also no backward ants are generated. At the end we compare our results with the basic AntNet algorithm results.

Network management and service deployment has thrown new challenges with integration of applications and services in the data networks. Admission Control (AC) is a key mechanism to keep services under controlled load to ensure required Quality of Service (QoS) levels and honor the service level agreements based on priority. The priority can be policy based as in case of government and military networks or based on revenue model or purely based on application sensitivity. The contemporary techniques are based on either rejection of the new flow or pre emption of low priority flow when sufficient capacity is not available. We present a novel approach based on graceful degradation for flow admission called as Inverse Taxation model. The proposed solution also supports the requirement of Military QoS (MQoS).

Today we pack radio waves into the air as tightly as possible. New radio technologies require unique hardware appropriate to its way of transmitting data. To minimize interference, each is restricted to its specific band. As user demands for data services and data rates steadily increase, efficient spectrum usage is becoming a critical issue. However recent measurements hint that 90 % of the available bandwidth is wasted [1]. Hence the need for Software Defined Radio (SDR) or Cognitive Radio (CR) arises. SDR enhances the ability to transmit and receive data using a variety of protocols and modulation schemes (enabled by reconfigurable software rather than hardware) [12]. Furthermore, as the name suggests, such radios can even become "cognitive". As dictated by the software, these radios can adapt their behavior to their wireless surroundings without user intervention.

In this paper we are presenting a Localization System for a Mobile Server based on Bluetooth Signal Parameters received from Multiple Bluetooth Devices in range. Though Bluetooth technology allows us to keep a low budget and low power system but at the same time it adds a tradeoff of accuracy. Therefore before predicting the distance first we create a lookup table with RSSI and Distance. We calculate the RSSI value by taking a large number of measurements for various distance and picking up the value that occurs most frequently by making the histogram. When we are predicting the distance we are taking reading from the Heading Sensor and Odometer attached to the mobile server and passing it on to an Extended Kaman Filter which model the noise associated with the system.

Networking has become an integral part in day to day life. Basic knowledge of network components plays a significant vital role in understanding any network either wired or wireless. This paper mainly focuses on description and working of basic components required to setup a network and also a discussion on few network issues like how to assign IP addresses etc and a sample design of wired and wireless network.

Human face detection is concerned with finding the location and size of every human face in a given group image. Face detection plays a very important role in human computer interaction field. It represents the first step in a fully automatic face re-cognition, facial features extraction, and expression recognition. There are many techniques used in face detection, each one has its advantages and disadvantages. The face detection system presented in this paper is a hybrid of known algorithms. First stage of the proposed method is applying skin color detection algorithm to specify all skin locations in the image. Second, face features detection like eyes, mouth and chin In experiments on images of group photos having upright frontal faces with any background our system has achieved high detection rates and low false positives.

Human face detection is concerned with finding the location and size of every human face in a given group image. Face detection plays a very important role in human computer interaction field. It represents the first step in a fully automatic face re-cognition, facial features extraction, and expression recognition. There are many techniques used in face detection, each one has its advantages and disadvantages. The face detection system presented in this paper is a hybrid of known algorithms. First stage of the proposed method is applying skin color detection algorithm to specify all skin locations in the image. Second, extract face features like eyes, mouth and nose. At the last, a verification step is applied to ensure that the extracted features are facial features. In experiments on images of group photos having upright frontal faces with any background our system has achieved high detection rates and low false positives.

In an intelligent tutoring system (ITS), the domain expert should present relevant domain knowledge to the tutor so that it will be able to guide the learner during problem solving. However, in several domains, this knowledge is not predetermined and should be captured or learned from expert users as well as from intermediate users. Our hypothesis is that, knowledge discovery (KD) techniques can help to build this domain intelligence in ITS. This paper proposes a framework to capture problem-solving knowledge using a clustering approach of data and knowledge discovery based on a combination of clusters. The framework has been implemented and is used to discover new meta knowledge from the clusters obtained which will serve as a problem space guiding the learners in problem-solving situations. To achieve this two clustering algorithms COBWEB and CHAMELEON are applied. Results show that CHAMELEON yields better clusters than COBWEB.

In this work a mathematical analysis for handoff latency and packet dropping probability at different anchor agents in a general n-layered architecture has been made. Through the analysis we want to find an optimal level of hierarchy with respect to handoff latency and packet dropping probability. We assume that each of the anchor agents in the network maintains an M/M/l/K queue. Analysis shows that handoff latency decreases by a ratio of 25-35% with the addition of a new layer up to layer three, around 15% decrease on adding fourth layer and a negligible decrease of 2-3% beyond layer four. Also, packet-dropping probability is directly proportional to the offered load, which in turn is dependent on the number of mobile nodes. As the number of layer increases, the coverage area of the anchor agent as well as the mobile nodes under its coverage increases. A 2-5% of the packets are dropped up to layer four and beyond which it exceeds 5%. A 5% handoff dropping is not considered to be acceptable. So, taking both, handoff latency and packet dropping probability in anchor agent, a three-layered architecture may be considered optimal.

Mobile Ad Hoc Networks (MANET) represents multifaceted distributed systems, allowing no preexisting communication infrastructure and dynamic topology. To facilitate effective communication within such network a routing protocol is used to discover routes between nodes. The goal of the routing protocol is to have an efficient route establishment between a pair of nodes, so that messages can be delivered in a timely manner. The growing interest in mobile ad hoc network techniques has resulted in many on demand routing protocol proposals. But detecting events and attacks in on demand routing protocol is a difficult task. The proposed malicious node detection scheme monitors several parameters on each node in DSR. Suggested scheme analyzes that some intermediate node might act selfishly to drop packets for other nodes in order to save their battery life. Though there have been many works in the recent years on existing routing protocols, the node detection for packet drop scheme amongst the node is not adequately addressed. The paper focuses on the vulnerability and potency of DSR in brief. The results of NS2 simulator demonstrates that proposed scheme can accurately detect malicious node code caused by network layer attack. Further, the results corroborated using comparative analysis of each node.

This paper presents a comparative analysis of call set up times, MOS (Mean Opinion Score), packet end to end delay and packet loss for the H.323 and SIP (Session Initiation Protocol) signaling schemes used in Voice Over IP (Voice over Internet Protocol) calls. We compare voice performance parameters like MOS, delay, jitter and call set up times and establish the differences in performance of these two VoIP protocols through an opnet simulation. This detailed simulation study is performed over H.323 and SIP networks where we have shown that the H.323 network performed better in terms of call set up time and packet end to end delay for the signaling messages. However, MOS for the voice packets in both the networks was expectedly the same as the same network topology was used for both the signaling protocols. There has been an influx of a large number of signaling and transport protocols over IP networks, giving rise to unacceptably large delays, most unsuitable for real time applications. SIP and H.323 are used for establishment and release of Voice aver IP calls as well as Video and Media calls. Both these protocols play a very important role in terms of optimizing the call set up time and call reliability and flexibility over IP networks for real time applications like voice and video.

A number of neighbor-monitoring, trust-building, and cluster-based voting schemes have been proposed in the research to enable the detection and reporting of malicious activity in ad hoc networks. The resources consumed by ad hoc network member nodes to monitor, detect, report, and diagnose malicious activity, however, may be greater than simply rerouting packets through a different available path. In this paper we present a method for determining conditions under which critical nodes should be monitored, describes the details of a critical node test Simulation, presents experimental results, and offers a new approach for conserving the limited resources of an ad hoc network IDS.

Mobile ad hoc networks (MANETs) are infrastructure less network consisting of mobile nodes, with constantly changing topologies, which communicate via wireless medium. Routing of packets is done through the co-operation of the relay nodes when source and destination are not in direct transmission range. Because of the selfish nature of the nodes, the nodes would not transmit the packets from source to destination. Pricing is one method to stimulate node co-operation. The requirements of the route differ with the type of application. There are certain applications which require QoS route and which do not require. For the applications which require QoS route, the source node has to pay a higher cost in order to transmit the packets. The parameters used to obtain QoS route are bandwidth, delay and jitter. In this paper, we propose auctions in order to get QoS route for lesser cost.

In this paper, we present a weighted linear parallel interference canceller (LPIC) where the multiple access interference (MAI) estimate in a stage is weighted by a factor before cancellation on Rayleigh fading and diversity channels. We obtain exact expressions for the average signal-to-interference ratio (SIR) at the output of the cancellation stages which we maximize to obtain the optimum weights for different stages. We also obtain closed-form expressions for the optimum weights for the different stages. We show that this SIR-optimized weighted LPIC scheme clearly outperforms both the matched filter (MF) detector as well as the conventional LPIC (where the weight is taken to be unity for all stages), in both near-far as well as non-near-far conditions on Rayleigh fading and diversity channels.

Network centric warfare is the latest military doctrine that promises to increase combat power enormously. Network centric operations, as they are called presently, imply sharing of information among all the participants to improve situational awareness. The requirement is to have self synchronization in the network without dependence on fixed infrastructure. This article is an overview of such networks and the performance issues involved.

TCP has become the dominant protocol for all network data transport because it presents a simple uniform data delivery service. With the growth of high performance networking, a single host may have simultaneous connections that vary in bandwidth. Consequently, connections on a single host can and will scale in bandwidth by several orders. TCP, now, requires queues proportional in size to a path's bandwidth. Traditional statically fixed mechanisms for allocating and limiting TCP queue space fall short on today's Internet, and often limit throughput only a small fraction of the available bandwidth specially for long- fat network (large bandwidths and high round-trip times). The paper proposes a novel linux kernel based TCP tuning approach to meet the above requirements.

Supporting scalable and efficient routing and service provisioning in MANET has been a big research challenge. Hierarchical service provisioning is flexible and takes advantage of centralized and distributed service provisioning schemes. A hierarchical structure is created by dividing the network into manageable square zones called cells. Every cell in the hierarchy has an access point and the entire region has an rendezvous point. The existing techniques choose the leaders based on Zone ID or geographic hash function. This paper aims at selecting an adaptive coordinator that can meet the QoS requirements such as remaining battery power, node mobility and node position. Such scheme can be robust against the unpredictable faults in MANETs.

With rapid development of processors, multi-core processors occupied the main market due to their superior performance and power characteristics. Threads run concurrently on a multi-core processor and share the processor's the second-level (L2) cache. Cache allocation and sharing is critical to the effective utilization of multi-core processors. Unfair CPU cache allocation can easily delay the critical task and cause serious problems, such as thread starvation, priority inversion, and inadequate CPU accounting. To solve these problems, this paper proposed a compensation policy scheduling algorithm which can decrease system variability and improve system performance effectively. The experiment results show that the system variability adopting compensation policy scheduling algorithm is lower than that using conventional scheduling algorithms. Consequently, compensation policy scheduling algorithm improves the stability of system and applications effectively on multi-core processors.

Based on the research and design of flood control and disaster relief system in the aspects of networking, system structure and interface, etc, this paper realizes that the system provides as much as 2Mbps ascending and descending wireless data service, real-time multimedia information for flood control and disaster relief and real-time information support for decision-making and command under the condition of occupying 4MHz bandwidth.

Locating a telecommunication fraud in masses of call records is more difficult than looking for a needle in a haystack. Callers are not similar, so calls that look like fraud for one account may look like expected behaviour for another, while needles look the same. One of the best data mining technologies available is visualization because graphical display methods often offer superior results compared to other more conventional data mining techniques. This paper presents Sawang, a graphical investigation tool specifically built for recognizing possible fraudster collaborators through call data records.

This paper mainly discusses about the Pricing Strategy WebSim, a web-based simulator using system dynamics methodology in decision making process of pricing strategies of voice telephony business. System dynamics methodology is one of the Operation Research (OR) discipline, whereby their conceptual modeling can then be converted into computing models using POWERSIM Studio 2005 software. A mathematical model simulating the growth of subscribers, revenue, traffics, cost and profit of voice telephony business has been made available for use via the Internet. The required input variables are provided by the user and results of multiple simulation runs can be viewed and compared via tables and graphs. The Powersim Software Development Kit (SDK) provides the Application Programmers Interface (API) for bridging the simulation model with the web application. By building a web application for system dynamics simulation model, cost saving is realized by buying a single license and deliver updated versions to multiple users.

the fact that cloud computing systems (formally known as pervasive computing systems) are typically embedded or invisible, making it difficult for users to know when these devices are collecting data. So privacy appears as a major issue for this environment In this paper we propose a User-centered privacy and trust Model which provides user control over data, identity, location, and time privacy with less than 10% of unobtrusiveness.

In order to explore problems facing by local Small Medium Enterprises (SMEs) in adopting Enterprise Resource Planning (ERP) systems, this paper seeks to investigate what are the barriers to ERP system adoption by SMEs? The research was conducted in a Malaysian medium-sized company that planned to adopt ERP systems. Prior researches have identified that high cost; lack of knowledge; highly centralized structure; and issue of misfit to be barriers to ERP adoption by SMEs. From the case study, apart from the previous mentioned factors, the company has to do without a project champion and influenced by the perceived risk associated ERP systems implementation. Limitation of the research is that it was based on a single-case study, imposes care in generalizing the results of the study. This research, however, allows the identification and understanding of barriers to ERP adoption in local setting.

The inherent presence of friction in motion control system has been one of the major sources of performance degradation in terms of slow responses, steady state accuracy, poor tracking and or limit cycles near the reference position. Motivated by the need for simple and at the same time effective friction model, an AI-based (non-parametric) friction model using an adaptive Neuro-Fuzzy inference system (ANFIS) is proposed in this work to estimate the non-linear friction in a motion control system. The effectiveness of the developed model in representing and compensating for the frictional effects is evaluated experimentally on a rotary experimental motion system, and the performance benchmarked with a parametric based model. The results show ANFIS as a viable and better alternative to mathematical-based techniques in representing and compensating friction effects.

In this paper, a full analytical and exact expression form of turn-on time delay, t_on, of degraded bulk uncooled semiconductor laser diode (DBUSLD) has been presented in terms of nonradiative, A_nr , radiative, B_r , Auger recombination coefficients, C_auger, cavity dimensions, threshold carrier density, N_th,, injection current, I_inj, number of "0" bits preceding the considered bit. N_bit, bit-rate, Brate and temperature of operation, T. Also we included, in addition to the mentioned parameters, dark defect (DD) parameters, i. e. number of DD, n_DD and width of DD, w_DD. In addition, an exact and full analytical expression form of carrier density, N, corresponding to the current flowing through laser active region, I, and in term of all the above mentioned parameters has been derived which can be used to determine any value of N corresponding to I exactly, therefore, the temperature dependence (TD) of threshold carrier density of DBUSLD (which is used in ton calculation) is calculated corresponding TD of threshold current of the device. Simulation results show that worst case of DBUSLD is when operates with large n_DD and at high temperature degree.

This research discusses a pressing issue involving minors and adult materials online. In specific, researchers proposed a framework based on user created content (UCC), technology availability, parental monitoring and internet literacy in an Australian context. The effects of exposure to adult material at a young age are damaging and the increase of internet literacy amongst minors coupled with the spread of UCC based applications is even more concerning.