字幕表 動画を再生する 英語字幕をプリント Hey downloaders and downloadettes, Trace here for DNews! If you’re one of the lucky few mobile phone users who have been grandfathered in to an unlimited data plan, your days are numbered. Companies left and right are dropping unlimited data or targeting those using more than, say, 200 gigabytes a month. Now, that certainly sounds like a lot, and maybe even like some users are abusing their unlimited plans. 200 gigs is about 200 hours of Netflix streaming, or 3 and a third marathon sessions of Game of Thrones. Clearly, these companies are just trying to recoup their costs. Or are they? Okay, data is sent over the air, by electromagnetic radio waves, similar to the waves used by radio, television, and WiFi… phone carriers in particular are limited to a certain spectrum. Mobile data tends to run in the 800 megahertz range. But that range means there is a limited amount of physical space for all the data to flow through. The reason is that each layer of the wave can only hold a certain amount of information. Basically, a cell phone has a virtual pipeline from the phone to the nearest cell tower, which only has so much space in it. You can only send a certain number of bits per second through your personal pipe. In real life, this capacity is determined through something called “Shannon’s law”, which calculates the physical limit for the amount of data that can be transmitted per second, while being bombarded with “noise” of all the other electromagnetic force flying through the air. So, when you upgrade your phone from 3G to LTE, you’re upgrading the encoding of information that you can fit into each slice of the electronic magnetic spectrum, and also how much of the spectrum is being used at once: basically, you’re getting a bigger pipe. And that’s why each upgrade makes your wireless speed faster. But those who stream hundreds of gigabytes from one device take up larger amounts of that over-the-air bandwidth that other people could be using at the same time. Even though we’ve never come close to this limit defined by Shannon’s law, our LTE pipes are basically now full. To deal with this problem, companies need to either install more cell phone towers for the data, or develop new technologies which allows us to send data better. And infrastructure development is incredibly expensive. Sprint has plans to spend $15 billion dollars over three years just to add and upgrade new cell towers, for example, while AT&T, they're spending $3 billion dollars to bring LTE to Mexico. So plans to shaft the 200 gigabyte club might not just be about the money, but about actually freeing up some space for the rest of their customers. The real cost of getting the data from those towers to you is actually way more difficult to figure out. The information is proprietary, and of course, most of the companies don’t share it. When it comes to wired transmission, one independent service provider in Canada, Radiant Communications, said the cost is less than 5 cents per gigabyte. Netflix claims it’s about 1 cent. Of course, these are both established companies with infrastructure that's already built. The cost of wired and wireless data depends on a variety of factors, including how much infrastructure they have available and when you use your data, because you might use it at a high traffic time. One thing we do know about is how much texting costs. As it turns out, texting is virtually free from a purely “data transfer” standpoint. Your phone is constantly in communication with cellphone towers, it is ALWAYS sending information to let the tower know you’re still there, which is how cell phone tracking is possible. But when you send a text, it simply piggybacks off the existing communication, and in particular, occupies, what is referred to as “unused space”. It’s like going on a road trip and bringing along an extra passenger. Although it is nice to have them pitch in for the cost of the trip, the cost overall is roughly the same with or without them. And, in this analogy, instead of chipping in for, say, a tank of gas, the passenger is actually paying for a tanker-truck full of gas. Texting costs have been estimated to be up to 7,314 percent higher than what companies would charge for the equivalent amount of data, which is only about 1/1000th of a penny. And while modern unlimited texting plans don’t generally comprise such insane overages, texts still cost more than 1/1000th of a cent for the end user… for communication that the cell company was already gonna do anyway. Whoever thought of that “charging for texts” thing, they definitely got a corner office. And a parking spot. But what if you want to get in touch with astronauts in space? Can you send them a text? Or maybe… you can use a radio invented in the 1890s. For more about that super sounding communication, check out this video right here. Are you afraid of losing your unlimited data plan? Tell us about it in the comments, make sure you subscribe so more DNews and thanks for watching.
B1 中級 米 無制限のデータを維持することが不可能な理由 (Why Unlimited Data Is Impossible To Maintain) 182 18 李柏毅 に公開 2021 年 01 月 14 日 シェア シェア 保存 報告 動画の中の単語