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What is quality of service quality of service is providing a better quality to certain applications

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at the detriment of other applications in the same way that on the roads certain vehicles are poor motorized

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over others such as ambulances or buses.

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We approach rising certain traffic types.

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In other words making sure that they go to the front of the queue.

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As an example versus other traffic types.

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Certain traffic types such as voice or video are delay sensitive they can't handle a lot of delay so

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they will be poorer terrorized over traffic types that can handle delay such as FCP.

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It's also called managed unfairness.

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We are introducing unfairness into the network prioritizing certain traffic types over other traffic

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types.

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As an example a very important phone call from the CEO would be proud to rise over someone watching

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YouTube videos for the CPA exam.

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You need to be aware of three traffic types and to their traffic characteristics.

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Firstly we have data data traffic is generally boosted and greedy that's not always the case.

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But generally data applications such as FCP will grab as much bandwidth as they can.

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If you give an FCP application two megabits per second it will take two megabits per second.

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If you give it four megabits per second it's going to take four megabits per second.

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So data is Bersih and greedy.

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It's sometimes smooth and benign.

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In other words it doesn't grab all the bandwidth that you give it.

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But in a lot of cases data applications of boosting and greedy.

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They also tend to be dropping sensitive.

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In other words if a packet is dropped it doesn't matter because it's a retransmission.

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A lot of data applications use TTP which read transmits data if packets go missing.

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It's also delay insensitive.

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So as an example if packets are delayed by 500 milliseconds it's not a major problem.

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Now this really depends on the type of data sent.

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There are two major categories of data applications.

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We have interactive data applications and non interactive data applications telnet.

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As an example is interactive a large delay will degrade the user experience.

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But if you downloading a file using FCP delay isn't that important.