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Mobile Ad-hoc Networks (MANETs) is a continuously self-configuring, self-organizing infrastructureless network of mobile nodes connected wirelessly. Therefore the recurring link breakages can occur in MANET, also the network topology is assumed to be highly dynamic leading to changes in the routing table, which is a key factor to the MANET performance. In this paper, a new protocol called as opportunistic auto rate anthocnet protocol is proposed that can be utilized in MANETs for improving the throughput while adapting to the change in the network topology. The original anthocnet and proposed opportunistic auto rate anthocnet protocol are simulated on the Network Simulator 2 (NS2) to compare the performance of these two protocols. The main objective of this research is to compare the throughput performance of existing anthocnet protocol and proposed OAR-Anthocnet protocol under different network conditions. The obtained simulation result shows that the throughput of the proposed OAR-Anthocnet protocol is nearly twice as compared to the anthocnet protocol due to its opportunistic nature.

Growth of Internet of Things (IoT), in leaps and bounds has diverted major attention towards wireless sensor networks and its associated routing protocols. Use of a routing protocol which is not suitable for a particular scenario may result in a loss of packets. This in turn will lead to retransmissions which has an obvious impact on bandwidth, the amount of power being consumed among various other parameters. These issues are to be considered since IoT involves Low Power and Lossy Networks (LLNs) formed using low power devices. Hence for IoT applications, Routing Protocol for LLNs (RPL) is custom designed. The objective of this study is to describe the RPL protocol and the operating system contiki which paves the way for its reliable implementation. Also, a collective information regarding RPL implementation is provided for better comparison.

LTE (Long Term Evolution) has been standardized by 3GPP and is now commercially being deployed to offer higher data throughput as well as low data transfer latencies. The LTE has to ensure seamless handover for delay-critical services. Handover procedure always tries to make user equipment (UE) associated with the most suitable eNodeB. Prediction of handover under various mobility conditions is very complicated. The LTE standard supports handover parameters to make the handover decision and to choose the target eNodeB. Thus requires careful handover parameter setting to make handover successful. At the time of handover procedure the handover-related signaling messages are transmitted using shared radio channel. Packet loss is the key cause of handover associated signaling message drops at the wireless link. A number of error consequences occur at the control channels has impact on the transmission of handover signaling messages. The error in transmitting handover-related signaling messages affect all other data or control packets causes the handover failure and delay. We analyze the influence of handover parameters in an error-prone channel. The handover performance is investigated with changing User Equipment (UE) speeds in ns-3. We have observed all of these parameters need to be carefully selected with respect to the error rate in the wireless radio channel.

LTE (Long Term Evolution), a 4G mobile communication standard has a support for higher data rates and lower latency. Since LTE is completely an Internet Protocol (IP) based technology, Network operators of LTE can handle voice via a “fall-back” technique by using previously existed circuit switched networks. To avoid this, Voice over IP (VoIP) services need to be used to deliver the voice over IP networks, such as Internet. Voice Codec is one of the critical components in VoIP used to convert analog signals to compressed digital packets and vice-versa that can be sent over the internet. But there are different kinds of codecs exist that optimize the voice stream based on bandwidth and application requirement. Unfortunately, there is no standard codec that is acceptable for all circumstances, some codecs provides better quality, some other uses lesser bandwidth. All these features will effect on the ultimate selection of codec by an organization. This paper focuses on the quality of service (QOS) analysis of VoIP traffic over LTE by configuring different voice codecs such as G.711, G.722.2, G.723.1 and G.729. To analyze the performance of these codecs ns-3 simulator is being used since its core has a support for LTE models. The comparative study of above selected VoIP codecs over LTE network in terms of Packet Loss, End to End delay, Jitter, and Throughput in normal and error prone scenarios has been done. From the analyzed results and the performance evaluated, the selection of codec will become easy to provide better VoIP services for customer satisfaction.

The brain is the central control unit of human body. Tumor affects the brain means it causes the death of the patient if it is not diagnosed in the early stage. Among the different available imaging modalities, Magnetic Resonance Image (MRI) is a better method for area calculation and classification based on the grade of the tumor. MRI doesn't produce any harmful radiation. Nowadays there exists no automatic system to detect and identify the grade of the tumor. This paper proposes a technique to segment and classify the brain tumor from MRI. It helps doctors to plan further treatment or surgery. This paper used Ostu's threshlding for preprocessing. The tumor is detected with the help of K-Means clustering. Discrete wavelet transform(DWT), Gabour wavelet and GLCM features are extracted. The feature set reduction is made possible by Principal component analysis(PCA). Finally the tumor is classified as benign or malignant using support vector classifier(SVM). Linear kernel, polynomial kernel, and RBF kernel were applied and the result shows that liner kernel produces more accuracy.

Managing keys for secure communication and routing in Mobile Ad-hoc Network (MANET) is a significant and challenging task due to its battery constrained functionality, dynamic topology, minimal physical security and varying capacity links. Identity based key management techniques have less memory storage cost and simple key management process compared to other methods such as Public Key Infrastructure (PKI). In this paper we propose identity based symmetric key management solution using Elliptic Curve Cryptography (ECC) and bilinear pairing concept to generate the symmetric keys to secure communication and routing in MANETs. We realized the elliptic curve point generation, addition and multiplication functionalities from scratch and tested them against standard implementations like PARI/GP. We modified the Ad-hoc On-demand Distance Vector (AODV) code to suit the security requirements and used them to validate secure communication on MANET testbed. We show that proposed identity based symmetric key management scheme is fast, simple, reliable, computationally less expensive and has less storage cost.