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Network latency - Mobile Web Development

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    One of the surprising things about network speed is that a
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    lot of what determines the end to end speed of a
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    network in practice is not the throughput, how fast you can
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    push bits through the channel, but the latency, the time it takes
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    to get a response from the other end. Let's take a
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    look at where that latency comes from. For each HTTP request, even
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    after we've gotten the radio to wake up, we have to
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    do a DNS lookup to figure out what that domain name server
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    actually means in terms of IP number. We have
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    to make a socket connection to that site. We
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    have to actually send the HTTP request and then
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    we actually get our data back. Each one of
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    these steps takes time. On an LTE network, each
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    one of these requests takes between 240 and 500
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    milliseconds, depending on whether we already have a connection
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    going or not. On 3G, each request will take 600
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    milliseconds to 3.5 seconds, that's per every HTTP request.
Title:
Network latency - Mobile Web Development
Video Language:
English
Team:
Udacity
Project:
CS256 - Mobile Web Development
Duration:
0:57

English subtitles

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