Informatics Publishing Limited

P. Sai Kiran ¹, L. S. S. Reddy ²

Affiliations
1 Department of Computer Science and Engineering at Lakireddy Bali Reddy College of Engineering, Mylavaram, IN
2 Lakireddy Bali Reddy College of Engineering, Mylavaram, IN

Abstract

Head of Line blocking phenomenon is common in First in First Out (FIFO) nature queues. Head of line blocking problem becomes significant in wireless ad hoc networks using directional antennas as it uses FIFO queue which consists of packets intended for different directions. A packet on the top of the queue may block the remaining packets if it finds the medium busy in its intended direction, where as the packets in the queue intended for other directions may find the medium to be idle. In this paper we propose a method to address the Head of Line blocking problem that can be used for Medium Access Control protocol for wireless Ad Hoc networks using Directional Antennas. The present proposal is about processing the data packets in the queue ready for transmission in other directions when the data packet on top of the queue finds the channel busy in its intended direction. This method is independent of mechanisms used for sensing and transmission by a MAC protocol for directional antennas thus can be part of any MAC protocol using directional antennas with out much change to the protocol. We propose Individual queues for each beam direction and also propose to transmit all the packets waiting at a time once the medium is idle in the intended direction. Our results indicate that the method outperforms other methods proposed for avoiding head of line blocking while increasing throughput and reducing the end-to-end delay.

Keywords

Directional Antennas, Head of Line Blocking, Medium Access Control, Ad Hoc Networks.

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P. Sai Kiran ¹, L. S. S. Reddy ²

Affiliations
1 Department of Computer Science and Engineering at Lakireddy Bali Reddy College of Engineering, Mylavaram, IN
2 Lakireddy Bali Reddy College of Engineering, Mylavaram, IN

Abstract

Directional antennas usage for Medium Access Control (MAC) in Wireless Ad hoc networks has received much attention from researchers as it provides advantages like reduces signal interferences, increase in throughput and better channel reuse. Directional Antennas poses many challenges to be addressed while providing advantages in wireless ad hoc networks like Hidden terminal problems, Deafness, Deaf zone and head of line blocking problem. We observed the existing protocols does not address all the issues and found no protocol that had addressed all the issues. In this paper we propose S-MAC protocol for medium access control in wireless ad hoc networks using directional antennas. S-MAC uses dual channel approach and maintain separate queue for each beam direction. In S-MAC, we address all the challenges imposed by directional antennas and provide a solution to overcome or eliminate the issues. We observed S-MAC outperforms other protocols in terms of throughput while addressing all the issues.

Keywords

Wireless Ad Hoc Networks, Directional Antennas, Medium Access Control, Deafness, Deaf Zone, Head of Line Blocking.

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K. Balaji ¹, P. Sai Kiran ¹

Affiliations
1 Department of CSE,KL University, Vijayawada – 520001, Andhra Pradesh, IN

Abstract

Background/Objectives: Cloud computing offers various services with minimum management effort while provisioning resources via internet. Cloud clients are allowed to store their personal data at data centers, it will minimize storage maintenance in local systems. Methods/Statistical Analysis: Cloud computing environment facing huge issues with hardware and software vulnerabilities in maintenance and resources provisioning process. These vulnerabilities pose huge loss of data, confidentiality, privacy and availability. Findings: In this paper, we studied and concentrated on various attacks in Virtualization environment and the possible attack scenarios in each platform. Application/Improvements: In the final section, we studied and described all types of attacks.

Keywords

Confidentiality, Integrity, Privacy, Provisioning, Virtualization.

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V. Jhansipriya Marabathuni ¹, P. Dinesh ¹, R. Ravikumar ¹, P. Yamini ¹, P. Sai Kiran ¹, P. Hussain ¹, M. M. Prasada Rao ²

Affiliations
1 Department of Pharmaceutics, Bellamkonda Institute of Technology and Sciences, Podili, IN
2 Department of Pharm. Chemistry, QIS College of Pharmacy, Ongole, IN

Abstract

The buccal region of the oral cavity is an attractive target for administration of the drug of choice. Sustained release formulations have been developed and are gaining in popularity and medical acceptance. To increase bioavailability and prevent first pass metabolism of drug, Amlodipine besylate was embedded in sustained released buccal patch over period of 6 hour. The objective of present work was to characterize the effect of chitosan with PVP K-30 on water soluble drug by preparing mucoadhesive buccal patch. Each formulated batch was subjected to various evaluation parameters. The swelling percentage was found to be function of solubility of drug and PVP K-30. The mucoadhesive strength, vapour transmission and in-vitro released of water soluble drug through water insoluble chitosan base matrix were found satisfactorily. The AMB shows some suitability with those polymers.

Keywords

Buccal Patch, Sustained Drug Delivery, Bioadhesion, Mucoadhesive Buccal Delivery.

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