Seema Ansari

Certificateless ID-based authentication using threshold signature for P2P MANETs

As far as the security of MANET (Mobile And Ad Hoc Network) is concerned, it depends upon the secure authentication especially for P2P MANETs. Identity based encryption was introduced to construct Public Key without requiring a certificate. Therefore, certificateless authentication combined with threshold digital signature and efficient key generation using identities such as IP address, are the challenging issues in front of researchers. In this paper we have addressed the problem of identity based secure authentication employing well-known RSA algorithm and secret sharing to generate threshold signature on a message.

Analysis of MAC Strategies for Underwater Applications

Abstract This study aims at analyzing the performance of protocols designed for the control of Medium Access in the underwater environment using Underwater Acoustic Wireless Sensor Networks (UW-ASNs). Oceans today, are playing an eminent part in monitoring climate, storing and releasing Carbon dioxide, supplying foodstuffs, and shipping. The sectors that can benefit most from this research are industries dealing with oil and gas, fisheries, UW instrumentation, armed forces, research and exploration bureaus, etc. Existing terrestrial Wireless Sensor Networks (WSN) Medium Access Control (MAC) protocol which mostly use radio waves for communications are unsuitable for underwater atmosphere. Underwater sensor networks (UWSNs) using acoustic wireless networking finds application in the supporting tools for such applications. The unique properties of the UW acoustic communication path necessitate the need for new efficient, reliable MAC protocols to meet the challenges of propagation delay, multipath and fading and excessive power absorption at higher frequencies etc. Owing to the typical properties of acoustic wave propagation in the underwater atmosphere, the energy efficiency in UW-ASN is badly affected by the long propagation delay and data packet collisions, which hinders the transmission of the data packets that enables us to achieve collective monitoring tasks. This paper, present MAC protocols tailored for UWANs, the classification of MAC protocols, the state of the art, environment characteristics, challenges, and performance metrics in terms of throughput, propagation delay, energy consumption and quantitative analysis of some selected protocols. It also gives an insight of some challenges and open issues for future works. The analysis was made on UAN-CW-MAC protocol and UAN-Aloha, to understand the shape of the throughput curves for the protocol. The simulations were performed on network simulator ns3 to obtain the throughput curves for uan-cw mac with 20 nodes and uan-Aloha with 2–15 sensor nodes with one sink. The results obtained are shown for 20 simulation runs for each node.

Infomax and FASTICA using principle component analysis as preprocessor for airwave removal in seabed logging

This research aims to apply the FASTICA and Infomax algorithm in the field of seabed logging, by utilizing the Principal Component Analysis (PCA) as preprocessor. All the three algorithms are statistical algorithms used for signal deconvolution and are respectively in the field of Independent Component Analysis (ICA). In seabed logging (SBL) implies the marine controlled source electromagnetic (CSEM) technique for the detection of hydrocarbons underneath the seabed floor. The results from SBL, indicate the presence of Hydrocarbon, but due to the presence of noise, in the form of airwaves, interfere with the signals from the subsurface and tend to dominate the receiver response. Hence, the Infomax and FASTICA de-convolution algorithms are used, considering PCA as a pre-processor to filter out the airwaves which disrupt the subsurface signals within the receiver response. The results obtained from simulations and their comparative analysis, indicate that the results from the infomax algorithm are better.

Subsurface exploration of seabed using electromagnetic waves for the detection of hydrocarbon layers

This paper focuses on the detection of hydrocarbon layers under the seabed using Electromagnetic methods and to prove the relationship between the thickness and resistivity constrast of the hydrocarbon. Simulations have been carried out by varying the depth of seawater from 1000m to 100m and the resistivity contrast and thickness for each level of depth is also varied. The electric field is also measured using various simulation models and graphs over different offsets. The results obtained prove that the resistivity property of Hydrocarbon is directly proportional to the thickness, and at particular points the presence of hydrocarbon layer is clearly significant.

An end-to-end TCP throughput enhancement for Vertical Handovers in 3G wireless networks

3G networks provide access to network mobile users at multiple data rates. The lack of mobility support for mobile nodes, by the standard protocols originally developed to meet the requirements of stationary nodes in wired networks, implies that these standard protocols cannot be efficiently implemented in wireless networks. Transmission Control Protocol (TCP) considers packet losses during Vertical Handover transition period as congestion and activates congestion control algorithm as a result thereby degrading throughput. This throughput degradation can be enhanced through improved TCP congestion window adjustment architecture. A proactive approach is presented in this paper wherein congestion window is adjusted according to the new network while handover process is being completed, avoiding slow starts during this process to eliminate the delay in window adjustment for enhanced throughput. Simulation of proposed scheme was carried out in NS-2. Throughput was calculated for proposed scheme during upward vertical handover and downward vertical handover scenarios. The results of proposed scheme were also compared with a split connection and an end-to-end connection approach. The comparative analysis of the results indicate a throughput enhancement of 22% and 17% as compared to split connection and end-to-end connection approach for upward vertical handover whereas throughput enhancement of 37% and 21% as compared to split connection approach and end-to-end connection approach for downward vertical handover is achieved.

Comparative Analysis of MAC Protocols and Strategies for Underwater Applications

AbstractThis research focuses on the comparison of the throughput performance of MAC protocols designed for underwater acoustic networks. Our emphasis was to study the key features of the existing MAC protocols for underwater acoustic communications and provide analytical analysis where feasible. We compared some selected underwater MAC protocols like UAN-ALOHA, CSMA, MACA, MACA-EA and S-FAMA and analyzed their throughputs. We chose to evaluate possible improvements in the throughput of S-FAMA by using the retry mechanism. We found the retry mechanism only showed marginal improvement in the throughput. The proposed mechanisms may not have practical efficacy, however, this mechanism may be helpful in saving energy of the sensor nodes by preventing the repetition of the entire transmission cycle.

Filtration of Airwave in Seabed Logging Using Principal Component Analysis

In this research, Independent component analysis using Principal Component Analysis (ICA-PCA) technique has been applied in the field of seabed logging application for the filtration of airwaves. Independent component analysis (ICA) is a statistical approach for transforming data of multivariate nature into its constituent components (sources) which are considered to be statistically independent of each other. ICA-PCA is applied in the domain of marine controlled source electromagnetic (CSEM), called seabed logging (SBL) sensing method used for the detection of hydrocarbons based reservoirs in SBL application. ICA-PCA has not been applied before in SBL application, and therefore may reduce exploration costs in deep sea areas. The task is to identify the air waves and to filter them out, hence, the ICA-PCA algorithm is carried out for airwave filtration, at varying seawater depth from 100 m to 3000 m. It is observed that the results are favorable upto 2500 m depth. Upon increasing seawater depth, the component representing the presence of hydrocarbon becomes more dispersed, vague and indistinguishable.

Study and Analysis of the Internet Protocol Security and Its Impact on Interactive Communications

Internet Protocol Security (IPSec) is the defacto standard, which offers secured Internet communications, providing traffic integrity, confidentiality and authentication. Besides this, it is assumed that IPSec is not suitable for the protection of realtime audio transmissions as the IPSec related enlargement of packets and the usage of the Cipher Block Chaining (CBC) mode contradict stringent requirements. IPSec overhead of at least 44 bytes for each Internet Protocol (IP)-packet cannot guarantee Quality of Service (QOS) due to a bad wireless link by which the Ethernet flow control intercepts and makes a real time transmission impossible.

Efficiency enhancement through dynamic allocation of switching path in all-optical networks using GMPLS

The inability of wavelength conversion between links in All-Optical networks causes congestion and hence results in Packet loss. We have Proposed a GMPLS-Based All-Optical networks that would dynamically locate path for switching in case of congestion, using maximum utilization of Control Plane resources thus ensuring guaranteed QoS. This paper presents the mechanism to reduce the blocking probability in GMPLS by dynamically finding a route and selecting a wavelength in a manner that minimizes the overall blocking probability using Least Routing mechanism (LR). Simulation results confirm our analysis and furthermore, reveal that our proposal also complete major performance improvement in terms of blocking probability.