A hop-count and node energy based manet routing protocol

Mobile ad hoc network is a self-configuring network in which all participating nodes are mobile and consist of limited channel bandwidth and energy. Mobile devices are battery operated, and energy efficiency is a major issue for battery-operated devices in mobile ad hoc networks. Routing data packets from source to destination is the challenging task in mobile ad hoc networks due to node mobility and dynamic topology change in the network. Link failure or node energy depletion causes re-routing and establishing a new route from the source node to destination node which consumes extra node energy, reduces connectivity of the network and early partition of the network. Energy-related parameters consideration in routing is an important solution to enhance network lifetime. Several better performing routing schemes are presented and implemented for MANETs. Ad-hoc On-demand Distance Vector (AODV) routing protocol is one which performs well among similar routing protocols for MANET. AODV route selection base on either lowest hop-count or fresh sequence number. Many enhancements to AODV are proposed, which represents a better performance in comparison with original protocol. However, in a large network different paths to the destination could be found with the same hop-count. When efficiency is deliberated for those paths in quickly data transmission, each path performance varies in terms of throughput, end-to-end delay and packet delivery ratio due to the mobility of the nodes in the network. AODV routing protocol and enhancements suggested by other researchers do not give attention to such cases, and this paper proposes Hop-count and Node Energy based Routing Protocol (HNERP) which uses a multi-function routing strategy that incorporates with hop-count and node energy while making the routing decision. The proposed protocol is simulated by using NS2 and results show that HNERP performs better in term of packet delivery ratio and throughput, moreover it increases network lifetime and reduces end-to-end delay

Energy Aware Routing Protocol for Energy Constrained Mobile Ad-hoc Networks

Dynamic topology change and decentralized makes routing a challenging task in mobile ad hoc network. Energy efficient routing is the most challenging task in MANET due to limited energy of mobile nodes. Limited power of batteries typically use in MANET, and this is not easy to change or replace while running communication. Network disorder can occur for many factors but in middle of these factors deficiency of energy is the most significant one for causing broken links and early partition of the network. Evenly distribution of power between nodes could enhance the lifetime of the network, which leads to improving overall network transmission and minimizes the connection request. To discourse this issue, we propose an Energy Aware Routing Protocol (EARP) which considers node energy in route searching process and chooses nodes with higher energy levels. The EARP aim is to establish the shortest route from source to destination that contains energy efficient nodes. The performance of EARP is evaluated in terms of packet delivery ratio, network lifetime, end-to-end delay and throughput. Results of simulation done by using NS2 network simulator shows that EARP can achieve both high throughput and delivery ratio, whereas increase network lifetime and decreases end-to-end delay

Performance analysis of a single-node Hierarchical Time Sliced Optical Burst Switching (Hitsobs) network

Hierarchical Time Sliced Optical Burst Switching (HiTSOBS) is a time variant of OBS that aims at supporting Quality of Service. In this paper, we analyze the performance of HiTSOBS to determine the best burst size for a given number of time slots. These evaluations were carried with/without buffer at the core network. Simulation results demonstrate that smaller burst sizes such as 9 KB and 12.5 KB have better performance than bigger burst sizes such as 125 KB when buffers are assumed at the core network. However, without buffer at the core node, bigger burst sizes achieve better performance in terms of burst loss probability while smaller burst sizes have better delay performance

Performance measurement of free-space optical 980 nm channel using multiple sets of environmental conditions

In this paper the performance of the free space optics (FSO) based communication link is investigated in hot and dry weather which is a common atmospheric condition in Pakistan. To measure the performance of connectivity at different day time, a portable test-bed setup is launched to describe the performance of 980 nm FSO in hot and dry weather at various distances with a large aparture of transmitter and receiver. This test bed is capable to evaluate performance in terms of data transmission and signal strength with bit error rate. The results show that perfect alignment is a main concern along with data transmission and signal strength. The transmission performance is different during the day and the night time. Moreover the results also show the performance of FSO at the indoor is up to the mark and very little or no jerks in the streaming data considering perfect alignment and a short distance. The FSO at short distance can be aligned perfectly without the alignment tools. However, for longer distance, it requires to be perfectly aligned with the tool. In case of perfect alignment and clear weather, the transfer rate is up to the mark, but the signal strength varies during the day and the night time which causes the delay in the transmission. The performance analysis shows that the improvement of transmission channel is possible at the night time

A role-oriented content-based filtering approach: personalized enterprise architecture management perspective

In the content filtering-based personalized recommender systems, most of the existing approaches concentrate on finding out similarities between users’ profiles and product items under the situations where a user usually plays a single role and his/her interests persist identical on long term basis. The existing approaches argue to resolve the issues of cold-start significantly while achieving an adequate level of personalized recommendation accuracy by measuring precision and recall. However, we investigated that the existing approaches have not been significantly applied in the context where a user may play multiple roles in a system simultaneously or may change his/her role overtime in order to navigate the resources in distinct authorized domains. The example of such systems is enterprise architecture management systems, or e-Commerce applications. In the scenario of existing approaches, the users need to create very different profiles (preferences and interests) based on their multiple /changing roles; if not, then their previous information is either lost or not utilized. Consequently, the problem of cold-start appears once again as well as the precision and recall accuracy is affected negatively. In order to resolve this issue, we propose an ontology-driven Domain-based Filtering (DBF) approach focusing on the way users’ profiles are obtained and maintained over time. We performed a number of experiments by considering enterprise architecture management aspect and observed that our approach performs better compared with existing content filtering-based techniques

The effect of time slot parameters on slotted optical burst switched networks

In this study, the effects of time slot parameters on the performance of time domain switching optical burst switched networks (OBS) are studied. We investigate OBS networks where all core nodes are able to receive and send data. Network throughput is reduced when bursts are not able to secure necessary time slots for their transmission due to heavy contention at the core networks and lack of proper selection of time slot parameters. In this paper, we investigate the performance of slotted OBS when time slot parameters are varied. Time slot parameters investigated are: frame size, time slot size. Additionally, we analyse the effect of network size when time slot and other parameters are kept constant. Metrics used for evaluation are delay and throughput. Simulation results prove that given the same route, wavelength and time slot assignment algorithm, time slot parameters influence the overall network performance

Secure burst control packet scheme for Optical Burst Switching networks

Abstract—Optical networks are the most adequate platform for the transport of ever increasing bandwidth-hungry applications and services (BwGAS). Additionally, these networks cope with the continuous growth of the number of Internet users. Optical Burst Switching (OBS) paradigm is expected to be the backbone infrastructure of near-future all-optical Internet. In OBS, data and control packet known as burst header packet (BHP) are sent out of band (i.e., control packets and data bursts are carried by different channels) and it is sent ahead of the data burst to reserve necessary network resources for the corresponding burst. After the elapse of a predetermined time known as offset time, the data burst is sent with the hope that, the control packet was able to make necessary reservations. Sending the BHP ahead of the burst exposes the burst to different security challenges, particularly data burst redirection and denial of service attacks. If the BHP is compromised the corresponding burst will definitely be compromised. Less efforts have been dedicated to investigate control packet security issues in OBS. In this paper, we propose and evaluate a solution to address Data Burst Redirection (DBR) Attack in OBS networks. The solution is designed based on Rivest-Shamir-Adleman (RSA) public-key encryption algorithm. We evaluated the algorithm via computer simulation. Evaluation metrics are burst loss ratio and throughput. The obtained results demonstrate that, the proposed algorithm has succeeded in protecting the network against DBR attacks reducing the number of compromised BHP. In the future, the authors will work on denial of service issues considering reliability aspects