Essay Examples on Johns Hopkins University

CSMA CD shortcut for Carrier Sense Multiple Access Collision

Detect it is the protocol for carrier transmission access in Ethernet networks Moreover how network devices respond is defined by CSMA CD basically when two devices attempt to use a data channel at the same time and come across a data collision After that each device will wait for random time and will try again until it is transmission sent successfully Furthermore the CSMA CD method is specified in IEEE 802 3 and ISO 8802 3 standard The next figure shows the process of CSMA CD method The best example for CSMA CD is to assume that there are many people in a meeting having a conversation Each one has a chance to speak while the others listen to the one whose speaking and waiting for their opportunity to speak This resembles the Carrier Sense Multiple Access CSMA which is a protocol of a network that senses or listens to the network signal over a medium before any data is transmitted Once the speaker is over a moment of silence takes place After that other or others will try to speak and if more than one person speak at the same time collision will occur As a result one is allowed to speak while others are silenced this is known as collision detection CD However CSMA CD is not suitable for Wi Fi because Wi Fi networks have hidden node problem which is basically as shown in figure 2 assuming B is the Access Point station

2 pages | 482 words
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The Ethics of Self Driving Cars

By Elan Henry If you haven t heard of the Trolley problem it goes something like this A trolley is speeding down the tracks right towards a group of five people who are tied up and unable to get out of the way If the train hits them it is certain death Luckily you are standing right next to a lever If you pull this lever it will force the trolley onto a side track avoiding the people ahead but consequently sending the trolley directly towards another person who is also tied up and unable to move The question is which is the more ethical choice Do nothing and let the five people die or intervene and pull the lever sacrificing the person on the side track Most people are likely to pull the lever but what if the story is slightly changed Imagine the trolley is barely visible in the distance but heading directly toward the same five people This time instead of a lever you notice a large man standing dangerously close to the edge about half a mile from the group A thought pops into your head You could push the person onto the tracks killing him but forcing the train to stop before it reaches the group of people Is saving the five people still the most ethical choice It's not hard to see how situations like these might apply to the road

2 pages | 474 words
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Bride for most developing economies and a boost of Ego

Undertaking huge and ambiguous infrastructural initiatives remains a national bride for most developing economies and a boost of ego on their way to emerging market and or developed status China the world fastest growing economy for the past two decades continues to catch the attention of the globe when it comes to undertaking giant infrastructural development projects From the construction of the three gorges dam to the building of the world largest telescope and recently the manufacturing of the world largest marine aircraft the AG600 In the wave of these developmental initiatives the pronouncement of the One Belt One Road initiative OBOR by His Excellency Mr Xi Jinping President of the People's Republic of China 2013 has caught the attentions of many people both at home and abroad To the extent that some pundits term the initiative as unachievable and or unfeasible while others see it as a potential opportunity for global trade liberalization

1 pages | 305 words
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