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Wireless communication in our times today
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Reliable Broadcasting in Mobile Ad-Hoc Networks
ABSTRACT
In a mobile ad-hoc network, providing a reliable broadcast is one of the most important requirements. In broadcasting, a source node sends a message to all the other nodes in the network. Broadcasting operation is expected to be executed more frequently in mobile ad-hoc networks MANETs. So the number of retransmissions in the broadcast has to be minimized. The reliable broadcast service ensures that all the hosts in the network deliver the same set of messages to the upper layer. The protocols that are used in wired networks are unsuitable for deployment on MANETs, as these do not take into account the node mobility, network load and congestion. There have been a lot of protocols which are proposed for reliable broadcasting in MANETs. A straight forward way is by Simple Flooding [1, 2] which is very costly and very inefficient. The other protocols are Probability based methods [3], Area Based Methods [3] and Neighbor Knowledge Methods [4, 5, 6 and 7]. Also, efficiency and reliability conflict with each other. Hence it is hard to achieve both at a time with just one scheme. This paper will aim at proposing improvements for reliable broadcasting in MANETs.
1. INTRODUCTION
The drastic improvements in the wireless communications and portable wireless devices have made mobile computing a reality. Recently, Mobile Ad Hoc Networks (MANETs) has attracted a lot of attention and research. MANETs are made of a group of independent mobile hosts which communicate with each other. A mobile host may not be able to communicate directly with all the other hosts. So, the packets traverse various intermediate nodes before reaching the destination. All the nodes in the network assist in routing. The ad-hoc networks are created dynamically on the fly. The hosts are allowed to move around in the network. Routing protocols in ad-hoc networks should provide means to deliver packets to destination nodes given these dynamic topologies.
Applications of MANETs occur in battle-fields, major disaster and some business environments where networks need to be deployed immediately without any base stations or fixed networks.
Broadcasting is process by which a source node sends a message to all the other nodes in the entire network. Broadcasting operation is expected to be exe...
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Darwin made a scientific breakthrough. He did this by being an explorer throughout his life. He had help from many great scientists and by going on the Voyage of the Beagle. Darwinism impacted people in a huge way, and has helped scientists a lot. Even though many people put down Darwin's theory, it has helped scientists greatly. Charles Darwin is a very important person, and if he were alive today, he would probably be honored for his achievements.
Tom makes an assertion about “civilization going to pieces” during a dinner party with his wife, Jordan and Nick. The conversation begins after Daisy tells their guests that Tom has hurt her finger. Moreover, she then goes on to call him “hulking.” Nick then responds, “joking around,” by telling Daisy that she is making him feel “uncivilized (16).” Subsequent to this, Tom states “Civilization’s going to pieces. I’ve gotten to be a terrible pessimist about things” (15-16). In fact, Daisy even proves Tom’s compliance by asserting “Tom’s getting very profound. He reads deep books with long words in them” (16). Tom continues talking about his distrustful attitude and asks Nick if he had ever read a book titled “The Rise of the Colored Empires.” Tom explains that the book advises “the white race” should look out for themselves and not let anyone else take have power over of them. Also according to this book, they need to “produce all the things that go to make civilization” (20-21). Such an incident proves that society isn’t always well-mannered and deferential. Being racist is a characteristic of Tom himself throughout the novel. Society is depicted in a cruel way during the 1920’s. Racial and social segregation is something that is holding back civilization from developing thus making the American Dream not valid enough to achieve. Society isn’t able to fully expand because of the
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Analysis of the Environment of the Mobile Network System Executive Summary 3 Glossary of Abbreviations 4 Introduction 5 Recent History
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Climate change is having a multi-faceted effect on the pharmaceutical industry and Pfizer is no exception. For instance, changes in the climate affect microbial populations and their distribution. Global warming melts the polar ice caps, and causes sea levels to rise. This produces a warmer moist environment, which is a hospitable environment for pathogens to grow. Combine this with flooding, droughts, and food and water shortages and the likely hood of disease outbreaks increases significantly. Subsequently, when climate change causes diseases to spread, the people and domestic animals living in these regions affected need vaccines and medicines produced by companies like Pfizer to recover and sustain their health.
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