Sahel Alouneh

A Novel Approach for Fault Tolerance in MPLS Networks

There has been current demand on Internet service providers (ISPs) to provide quality of service (QoS) guarantees. Fault tolerance is an important factor that needs to be considered to maintain the network survivability. It is the property of a system that continues to operate the network properly in the event of failure of some of its parts. There is no solution until now that can provide a recovery with no packet loss and delay at the same time. In addition, network resources such as bandwidth have to be significantly utilized. In this paper, we propose a novel approach for fault tolerance in MPLS networks that can easily handle single or multiple path failures. Our approach uses the (k, n) threshold sharing algorithm with multi-path routing. Our approach guarantees to continue the network operation with no packet loss and recovery delay, and with reasonable network resource utilization

A novel path protection scheme for MPLS networks using multi-path routing

Multi-protocol label switching (MPLS) is an evolving network technology that is used to provide traffic engineering (TE) and high speed networking. Internet service providers, which support MPLS technology, are increasingly demanded to provide high quality of service (QoS) guarantees. One of the aspects of QoS is fault tolerance. It is defined as the property of a system to continue operating in the event of failure of some of its parts. Fault tolerance techniques are very useful to maintain the survivability of the network by recovering from failure within acceptable delay and minimum packet loss while efficiently utilizing network resources. In this paper, we propose a novel approach for fault tolerance in MPLS networks. Our approach uses a modified (k, n) threshold sharing scheme with multi-path routing. An IP packet entering MPLS network is partitioned into n MPLS packets, which are assigned to node/link disjoint LSPs across the MPLS network. Receiving MPLS packets from k out of n LSPs are sufficient to reconstruct the original IP packet. The approach introduces no packet loss and no recovery delay while requiring reasonable redundant bandwidth. In addition, it can easily handle single and multiple path failures.

FPGA hardware of the LSB steganography method

Steganography is one of the most powerful techniques to conceal the existence of hidden secret data inside a cover object. Images are the most popular cover objects for steganography, and thus the importance of image steganography. Embedding secret information inside images requires intensive computations, and therefore, designing steganography in hardware speeds up steganography. This work presents a hardware design of Least Significant Bit (LSB) steganography technique in a cyclone II FPGA of the Altera family. The design utilizes the Nios embedded processor as well as specialized logic to perform the steganography steps. The design balances the tradeoffs such as imperceptibility, quality and capacity.

Low power Wallace multiplier design based on wide counters

Multiplication is one of the most basic arithmetic operations. It is used in digital applications, central processing units, and digital signal processors. In most systems, the multiplier lies within the critical path and hence, due to probability and reliability issues, the power consumption of the multiplier has become very important. Moreover, as chips shrink and their power densities increase, power is becoming a major concern for chip designers. The ever increasing demand for portable applications with their limited battery lifetime indicates that power considerations should be a center stone in todays designs and the futures designs. Thus, all this has motivated us to provide a novel circuit design technique for a low power multiplier without compromising the multipliers speed. This paper presents a new power aware multiplier design based on Wallace tree structure. A new algorithm is proposed using high-order counters to meet the power constraints imposed by mobility and shrinking technology. Commonly used multipliers of widths 8, 16, and 32 bits are designed based on the proposed algorithm. The new approach has succeeded in reducing the total number of gates used in the multiplier tree. Simulations on Alteras Quartus-II FPGA simulator showed that the design achieves an average of 18.6% power reduction compared to the original Wallace tree. The design performs even better as the multipliers size increases, achieving a 5% gate count reduction, a 26.5% power reduction, and a 23.9% better power-delay product in 32-bit multipliers. Copyright

Transmitter Design and Hardware Considerations for Different Space Modulation Techniques

Space modulation techniques (SMTs), in which some or all of the data bits modulate a block of spatial constellation symbol, are promising candidates for future 5G wireless systems. They promise data rate enhancements while maintaining low energy consumption, hardware cost, and computational complexity. As such, they attracted significant research interest in the past few years. One of the major assets of SMTs is the assumption that they can operate with a single RF chain at the transmitter even though multiple antennas might be activated at one time instant. Thus far, this claim is anticipated in several research articles but the transmitter designs of the different SMTs with a single RF chain are not addressed yet in the literature. SMTs include different system configurations, such as spatial modulation, space shift keying, quadrature spatial modulation, and quadrature space shift keying. The required hardware components to implement a transmitter for each of these systems with the minimum number of RF-chains are discussed in this paper. In addition, hardware limitations and the impact of different hardware blocks on the overall system performance are discussed. Besides, a comparison among different schemes along with conventional spatial multiplexing algorithm in terms of power consumption, hardware cost, probability of error, and receiver computational complexity is presented. It is shown that some of these techniques can operate without any RF-chain while a single-RF chain is sufficient for other systems. Moreover, these schemes can be traded off in terms of energy savings, complexity, performance, and cost.

MPLS security: an approach for unicast and multicast environments

Multi-Protocol Label Switching (MPLS) network architecture does not protect the confidentiality of data transmitted. This paper proposes a mechanism to enhance the security in MPLS networks by using multi-path routing combined with a modified (k, n) threshold secret sharing scheme. An Internet Protocol (IP) packet entering MPLS ingress router can be partitioned into n shadow (share) packets, which are then assigned to maximally node disjoint paths across the MPLS network. The egress router at the end will be able to reconstruct the original IP packet if it receives any k share packets. The attacker must therefore tap at least k paths to be able to reconstruct the original IP packet that is being transmitted, while receiving k − 1 or less of share packets makes it hard or even impossible to reconstruct the original IP packet. In this paper, we consider the multicast case in addition to the unicast. To our best knowledge, no work has been published for MPLS multicast security. We have implemented our model and measured its time complexity on variable packets size.

Securing MPLS Networks with Multi-path Routing

MPLS network architecture does not protect the confidentiality of data transmitted. This paper proposes a mechanism to enhance the security in MPLS networks by using multi-path routing combined with a modified (k, n) threshold secret sharing scheme. An IP packet entering MPLS ingress router can be partitioned into n shadow (share) packets, which are then assigned to maximally-node disjoint paths across the MPLS network. The egress router at the end will be able to reconstruct the original IP packet if it receives any k share packets. The attacker must therefore tap at least k paths to be able to reconstruct the original IP packet that is being transmitted, while receiving k-1 or less of share packets makes it hard or even impossible to reconstruct the original IP packet

A Multiple LSPs Approach to Secure Data in MPLS Networks

MPLS security is an evolving issue which has been raised by many researchers and service providers. The basic architecture of MPLS network does not provide security services such as encryption. Therefore, MPLS does not protect the confidentiality of data transmitted. This paper provides a mechanism to enhance the security in MPLS networks by proposing a modified (k, n) Threshold Secret Sharing scheme where the n shares obtained are send over multiple disjoint paths. We have implemented our approach to measure its time overhead on packet transmission.

Image Steganography Optimization Technique

This paper presents a novel steganography technique which combines Discrete Cosine Transform (DCT) and Least Significant Bit (LSB). The objective is to maximize the capacity and invisibility of the secret image with minimal modification to the cover image (at most k-bits per block). The secret image is transformed to frequency domain using DCT. An algorithm is employed to construct the optimum quantization to embed the DCT coefficients in k-bits. The k-bits are then hidden in the LSBs of the cover image. The performance (capacity and peak signal-to-noise ratio) of the proposed method is compared with LSB.

Context-aware multifaceted trust framework for evaluating trustworthiness of cloud providers

With the rapidly increasing number of cloud-based services, selecting a service provider is becoming more and more difficult. Among the many factors to be considered, trust in a given service and in a service provider is often critical. Appraisal of trust is a complex process, information about the offered services quality needs to be collected from a number of sources, while user requirements may place different emphasis on the various quality indicators. Several frameworks have been proposed to facilitate service provider selection, however, only very few of them are built on existing cloud standards, and adaptability to different contexts is still a challenge. This paper proposes a new trust framework, called Context-Aware Multifaceted Trust Framework (CAMFT), to assist in evaluating trust in cloud service providers. CAMTF is flexible and context aware: it considers trust factors, users and services. When making recommendations, CAMFT employs a combination of mathematical methods that depend on the type of trust factors, and it takes both service characteristics and user perspective into account. A case study is also presented to demonstrate CAMFTs applicability to practical cases.