DYNAMIC AND AUTO RESPONSIVE SOLUTION FOR DISTRIBUTED DENIAL-OF-SERVICE ATTACKS DETECTION IN ISP NETWORK, 2009

Denial of service (DoS) attacks and moreparticularly the distributed ones (DDoS) are one of the latestthreat and pose a grave danger to users, organizations and infrastructures of the Internet. Several schemes have been proposed on how to detect some of these attacks, but they suffer from a range of problems, some of them being impractical and others not being effective against these attacks.

This paper reports the design principles and evaluation results of our proposed framework that autonomously detects and accurately characterizes a wide range of flooding DDoS attacks in ISP network. Attacks are detected by the constant monitoring of propagation of abrupt traffic changes inside ISP network.

For this, a newly designed flow-volume based approach (FVBA) is used to construct profile of the traffic normally seen in the network, and identify anomalies whenever traffic goes out of profile. Consideration of varying tolerance factors make proposed detection system scalable to the varying network conditions and attack loads in real time.

Six-sigma method is used to identify threshold values accurately for malicious flows haracterization. FVBA has been extensively evaluated in a controlled test-bed environment. Detection thresholds and efficiency is justified using receiver operating characteristics (ROC) curve.

For validation, KDD 99, a publicly available benchmark dataset is used. The results show that our proposed system gives a drastic improvement in terms of detection and false alarm rate.

Index Terms

Distributed Denial of Service Attacks, False Positives, False Negatives, ISP Network, Network Security

IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS,

VOL. 8, NO. 2, FEBRUARY 2009

Efficient Multi-Party Digital Signature using Adaptive Secret Sharing for Low-Power Devices in Wireless Networks

In this paper, we propose an efficient multi-party signature scheme for wireless networks where a given number of signees can jointly sign a document, and it can be verified by any entity who possesses the certified group public key.

Our scheme is based on an efficient threshold key generation scheme which is able to defend against both static and adaptive adversaries. Specifically, our key generation method employs the bit commitment technique to achieve efficiency in key generation and share refreshing; our share refreshing method provides proactive protection to long-lasting secret and allows a new signee to join a signing group.

We demonstrate that previous known approaches are not efficient in wireless networks, and the proposed multi-party signature scheme is exible, efficient, and achieves strong security for low-power devices in wireless networks.

Index Terms

Multi-party signature, distributed key generation, elliptic curve cryptosystems.

GUARANTEED DELIVERY FOR GEOGRAPHICAL ANYCASTING IN WIRELESS MULTI-SINK SENSOR AND SENSOR-ACTOR NETWORKS

In the anycasting problem, a sensor wants to report event information to one of sinks or actors. We describe the first localized anycasting algorithms that guarantee delivery for connected multi-sink sensor-actor networks.

Let S(x) be the closest actor/sink to sensor x, and |xS(x)| be distance between them. In greedy phase, a node s forwards the packet to its neighbor v that minimizes the ratio of cost cost(|sv|) of sending packet to v (here we specifically apply hop-count and power consumption metrics) over the reduction in distance (|sS(s)|−|vS(v)|) to the closest actor/sink.

A variant is to forward to the first neighbor on the shortest weighted path toward v. If none of neighbors reduces that distance then recovery mode is invoked. It is done by face traversal toward the nearest connected actor/sink, where edges are replaced by paths optimizing given cost.

A hop count based and two variants of localized power aware anycasting algorithms are described. We prove guaranteed delivery property analytically and experimentally

IEEE TRANSACTIONS ON IMAGE PROCESSING, VOL. ?, NO. ?, 1

HIERARCHICAL BAYESIAN SPARSE IMAGE RECONSTRUCTION WITH APPLICATION TO MRFM

This paper presents a hierarchical Bayesian model to reconstruct sparse images when the observations are obtained from linear transformations and corrupted by an additive white Gaussian noise.

Our hierarchical Bayes model is well suited to such naturally sparse image applications as it seamlessly accounts for properties such as sparsity and positivity of the image via appropriate Bayes priors. We propose a prior that is based on a weighted mixture of a positive exponential distribution and a mass at zero.

The prior has hyperparameters that are tuned automatically by marginalization over the hierarchical Bayesian model. To overcome the complexity of the posterior distribution, a Gibbs sampling strategy is proposed. The Gibbs samples can be used to estimate the image to be recovered, e.g. by maximizing the estimated posterior distribution.

In our fully Bayesian approach the posteriors of all the parameters are available. Thus our algorithm provides more information than other previously proposed sparse reconstruction methods that only give a point estimate.

The performance of the proposed hierarchical Bayesian sparse reconstruction method is illustrated on synthetic data and real data collected from a tobacco virus sample using a prototype MRFM instrument.

Index Terms

Deconvolution, MRFM imaging, sparse representation, Bayesian inference, MCMC methods

IEEE TRANSACTIONS ON PATTERN ANALYSIS AND MACHINE INTELLIGENCE, VOL. 31, NO. 2, FEBRUARY 2009

OFFLINE LOOP INVESTIGATION FOR HANDWRITING ANALYSIS

Study of Rough Set and Clustering Algorithm in Network Security Management Getting a better grasp of computer network security is of great significance to protect the normal operation of network system.

Based on rough set (RS), clustering model, security features reduction and clustering algorithm are presented, which provides a basis of network security strategies. Further research is to mine and process the dynamic risks and management of network security. Using the reduction methods, the simplified network security assessment data set is established.

The extraction by the decision-making rules is proposed and verified. Through the results, it is concluded that the method could be in line with the actual situation of decision-making rules.

Keywords

RS, clustering algorighm, network security, K-W method

IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS,

VOL. 8, NO. 5, MAY 2009

HIGH PERFORMANCE COOPERATIVE TRANSMISSION PROTOCOLS BASED ON MULTIUSER DETECTION AND NETWORK CODING

Cooperative transmission is an emerging communication technique that takes advantage of the broadcast nature of wireless channels. However, due to low spectral efficiency and the requirement of orthogonal channels, its potential for use in future wireless networks is limited.

In this paper, by making use of multi-user detection (MUD) and network coding, cooperative transmission protocols with high spectral efficiency, diversity order, and coding gain are developed.

Compared with the traditional cooperative transmission protocols with single user detection, in which the diversity gain is only for one source user, the proposed MUD cooperative transmission protocols have the merit that the improvement of one user’s link can also benefit the other users.

In addition, using MUD at the relay provides an environment in which network coding can be employed. The coding gain and high diversity order can be obtained by fully utilizing the link between the relay and the destination.

From the analysis and simulation results, it is seen that the proposed protocols achieve higher diversity gain, better asymptotic efficiency, and lower bit error rate, compared to traditional MUD schemes and to existing cooperative transmission protocols.

From the simulation results, the performance of the proposed scheme is near optimal as the performance gap is 0.12dB for average bit error rate (BER) 10 −6 and 1.04dB for average BER 10 −3, compared to two performance upper bounds.

Index Terms

Detection, coding, communication networks, and cooperative systems.

IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS

VOL. 8, NO. 2, FEBRUARY 2009

NOVEL PACKET-LEVEL RESOURCE ALLOCATION WITH EFFECTIVE QOS PROVISIONING FOR WIRELESS MESH NETWORKS

Joint power-subcarrier-time resource allocation is imperative for wireless mesh networks due to the necessity of packet scheduling for quality-of-service (QoS) provisioning, multi-channel communications, and opportunistic power allocation.

In this work, we propose an efficient intra-cluster packet-level resource allocation approach. Our approach takes power allocation, subcarrier allocation, packet scheduling, and QoS support into account.

The proposed approach combines the merits of a Karush-Kuhn-Tucker (KKT)-driven approach and a genetic algorithm (GA)-based approach.

It is shown to achieve a desired balance between time complexity and system performance. Bounds for the throughputs obtained by real-time and non-real-time traffic are also derived analytically.

Index Terms

Genetic algorithm (GA), Karush-Kuhn-Tucker (KKT), quality-of-service (QoS) provisioning, resource allocation, wireless mesh network (WMN).

IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS,

VOL. 8, NO. 2, FEBRUARY 2009

MULTI-SERVICE LOAD SHARING FOR RESOURCE MANAGEMENT IN THE CELLULAR/WLAN INTEGRATED NETWORK

With the interworking between a cellular network and wireless local area networks (WLANs), an essential aspect of resource management is taking advantage of the overlay network structure to efficiently share the multi-service traffic load between the interworked systems.

In this study, we propose a new load sharing scheme for voice and elastic data services in a cellular/WLAN integrated network. Admission control and dynamic vertical handoff are applied to pool the free bandwidths of the two systems to effectively serve elastic data traffic and improve the multiplexing gain.

To further combat the cell bandwidth limitation, data calls in the cell are served under an efficient service discipline, referred to as shortest remaining processing time (SRPT) [1]. The SRPT can well exploit the heavy-tailedness of data call size to improve the resource utilization.

An accurate analytical model is developed to determine an appropriate size threshold so that data calls are properly distributed to the integrated cell and WLAN, taking into account the load conditions and traffic characteristics.

It is observed from extensive simulation and numerical analysis that the new scheme significantly improves the overall system performance.

Index Terms

Cellular/WLAN interworking, resource management, quality of service, load sharing, vertical handoff, admission control.

SOBIE:A NOVEL SUPER-NODE P2P OVERLAY BASED ON INFORMATION EXCHANGE

In order to guarantee both the efficiency and robustness in the Peer-to-Peer (P2P) network, the paper designs a novel Super-node Overlay Based on Information Exchange called SOBIE.

Differing from current structured and unstructured, or meshed and tree-like P2P overlay, the SOBIE is a whole new structure to improve the efficiency of searching in the P2P network.

The main contributions are

1) to select the super-nodes by considering the aggregation of not only the delay, distance, but also the information exchange frequency, exchange time and query similarity especially;

2) to set a score mechanism to identify and prevent the free-riders. Meanwhile, the SOBIE also guarantees the matching between the physical network and logical network and has small-world characteristic to improve the efficiency.

Large number of experiment results show the advantages of the SOBIE including high efficiency and robustness by such different factors as the query success rate, the average query hops, the total number of query messages, the coverage rate and system connectivity.

Index Terms

P2P overlay, super node, information exchange, topology matching, free-ridding

AD HOC NETWORKS (ELSEVIER), VOL. 7, NO. 5, PP. 862-881, JULY 2009

OPTIMAL BACKPRESSURE ROUTING FOR WIRELESS NETWORKS WITH MULTI-RECEIVER DIVERSITY

We consider the problem of optimal scheduling and routing in an ad-hoc wireless network with multiple traffic streams and time varying channel reliability.

Each packet transmission can be overheard by a subset of receiver nodes, with a transmission success probability that may vary from receiver to receiver and may also vary with time. We develop a simple backpressure routing algorithm that maximizes network throughput and expends an average power that can be pushed arbitrarily close to the minimum average power required for network stability, with a corresponding tradeoff in network delay.

When channels are orthogonal, the algorithm can be implemented in a distributed manner using only local link error probability information, and supports a “blind transmission” mode (where error probabilities are not required) in special cases when the power metric is neglected and when there is only a single destination for all traffic streams.

For networks with general inter-channel interference, we present a distributed algorithm with constant-factor optimality guarantees.

Index Terms

Broadcast advantage, distributed algorithms, dynamic control, mobility, queueing analysis, scheduling

IEEE TRANSACTIONS ON MOBILE COMPUTING, VOL. 8, NO. X, XXXXXX 2009

RANDOMCAST: AN ENERGY-EFFICIENT COMMUNICATION SCHEME FOR MOBILE AD HOC NETWORKS

In mobile ad hoc networks (MANETs), every node overhears every data transmission occurring in its vicinity and thus, consumes energy unnecessarily. In IEEE 802.11 Power Saving Mechanism (PSM), a packet must be advertised before it is actually transmitted.

When a node receives an advertised packet that is not destined to itself, it switches to a low-power sleep state during the data transmission period, and thus, avoids overhearing and conserves energy. However, since some MANET routing protocols such as Dynamic Source Routing (DSR) collect route information via overhearing, they would suffer if they are used in combination with 802.11 PSM.

Allowing no overhearing may critically deteriorate the performance of the underlying routing protocol, while unconditional overhearing may offset the advantage of using PSM. This paper proposes a new communication mechanism, called RandomCast, via which a sender can specify the desired level of overhearing, making a prudent balance between energy and routing performance.

In addition, it reduces redundant rebroadcasts for a broadcast packet, and thus, saves more energy. Extensive simulation using ns-2 shows that RandomCast is highly energy-efficient compared to conventional 802.11 as well as 802.11 PSM-based schemes, in terms of total energy consumption, energy goodput, and energy balance.

Index Terms

Energy balance, energy efficiency, mobile ad hoc networks, network lifetime, overhearing, power saving mechanism.

IEEE TRANSACTIONS ON IMAGE PROCESSING, VOL. 18, NO. 6, JUNE 2009

ADAPTIVE FUZZY FILTERING FOR ARTIFACT REDUCTIONIN COMPRESSED IMAGES AND VIDEOS

A fuzzy filter adaptive to both sample’s activity and the relative position between samples is proposed to reduce the artifacts in compressed multidimensional signals.

For JPEG images, the fuzzy spatial filter is based on the directional characteristics of ringing artifacts along the strong edges. For compressed video sequences, the motion compensated spatiotemporal filter (MCSTF) is applied to intraframe and interframe pixels to deal with both spatial and temporal artifacts.

A new metric which considers the tracking characteristic of human eyes is proposed to evaluate the flickering artifacts.

Simulations on compressed images and videos show improvement in artifact reduction of the proposed adaptive fuzzy filter over other conventional spatial or temporal filtering approaches.

Index Terms

Artifact reduction, flickering metric, fuzzy filter, motion compensated spatio-temporal filter.