IoT Communications Part 2

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Hi, Matthew Clark, and this is less than 3.6 i o t communications Part two.

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In our previous lesson, we discussed coyote communication protocols that were in pink. In this lesson, we're going to discuss the protocols that Aaron White and remember, I've organized these in a certain manner. So by the time we get to the end of this lesson, let's see if you can guess how they're organized.

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So let's start with signee.

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Zig B is supported by the Zig B alliance. It uses the I Triple E 802.15 dot four standard, And that standard defines both the Mac layer and the physical layer. So Zig B adds on to the application layer and the network layer to that 802.15 dot for standard.

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Like Bluetooth, Zig B has a large installation base

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and you, but you're going to see this more in the industrial setting rather than a consumer setting.

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It's used to isolate with I, O. T. And machine to machine applications.

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It targets applications that it requires infrequent data exchanges at low rates, Um, and it's also known as the Security Protocol. It uses 128 bit A s symmetric encryption.

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It works in the 2.4 gigahertz band, has a range of about 100 m

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on data rate of 250 kilobits per second. Smiles. It has low power Operation High security. It's scalable, robust uses. The mesh network

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frowns. It has short range. I guess it's the same things that makes it a frown versus a smile.

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Um, low data speed and a low transmission. Right again, you'll see this a lot with the industrial area.

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So our next one is cellular and cellular communication may be a good choice for any I ot application that requires operation over long distances. It's good for physically remote locations. Think about on oil Rig that maybe, you know, miles and miles away from the nearest where human habitation

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and so range and data rates are gonna be a typical of cellular devices. Data rates are going to depend on you know, whether you're using three G four g five G

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and the range is gonna be basically the working range of a cell tower, which has a lot to do with how high it is and the transmitters rated power and the frequency of signal and all these other things.

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So smiles and frowns and smiles. It might be a good choice for, I guess, that remote applications. Um, they do have pretty much inexpensive boards that could be used in I o T devices of the frowns. It's gonna be basically the expense of the cellular plan. And if you plan on using large volumes of data, that could, uh, company. Very costly

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power consumption is something else to be considered,

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especially in remote locations.

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So let's talk about Laurel Land.

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Laura Wind is a low power protocol for wide area networks. It was assigned to support huge networks, as in smart cities with millions of low power devices. Similar protocol to be sick. Fox.

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It's Houston I. O. T. And machine to machine applications against Smart Cities Industrial I. O. T. It's considered a secure protocol with 128 bit A s symmetric encryption.

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I mean, it's great for applications where there is little access to electricity or physically difficult to reach locations and where cellular is just cost prohibitive.

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Andi, especially where you do not need instantaneous communications,

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has various frequencies from 125 kilohertz per hour toe up, and its range could be 2 to 5 kilometers in the urban area. Even Mawr, we have less things that could be in the way of the signal. And again, it has some of the same factors cellular

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regarding antenna and the performance and

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and so forth. Data rates are gonna be between 27 50 kilobits per per second.

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Um, smiles and frowns and smiles. It's intended again for low power battery operated devices. Um, Laura, when ends up the nodes, wake up on Lee at a fixed time. And, of course, that extends the battery life. It's good for short periodical communications

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frowns again, low bandwidth. It doesn't allow continuous sending because it only wakes up

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a certain amount of time. And it's not really good for large data transmissions.

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So let's talk about six. Lo pan. I don't know. I've I've just always loved this. This name. Six low pound sounds like a band or something,

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but six Lo Pan is actually an acronym of I. P V six over low power wireless personal area networks,

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so six Lo Pan offers an operability with other wireless 802.15 dot four devices as well as with devices with just any other I p Network link like Ethernet or WiFi. Um, with a simple bridge device.

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It's used in, UM I, o. T. And machine machine applications. Um, some of those applications could be general automation, smart homes, smart grid industrial i o T Smart agriculture.

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Unlike Coyote application protocol technologies like Bluetooth or Zig B

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six, Lo Pan is actually a network protocol that defines encapsulation and header compression mechanisms.

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It's used in many wireless protocols like Bluetooth, low energy, low energy WiFi. It's considered to be a secure protocol. 128 bit A s, um symmetric encryption

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optionally. You can use TLS. Our digital certificates can also be implemented.

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Some smiles and frowns so smiles its I. P V six support is designed for low data rate and battery operated applications. Supports mesh networks,

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frowns. Zig B is a very similar technology and its more popular

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So let's talk about Coop and M. Q T T.

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Um Coop is constrained Application protocol and M Q T T stands for message queue, toe limit tree transport.

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Both of those are mouthful.

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Eso. There are similar. Both of them run over I peep

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Coop uses UDP and MQ TT uses TCP

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eso. If you were to think about these, I kind of put two different examples up here. Ones of Facebook marketplace. You know, the one is of Twitter, of all things. But if you think about Coop, I kind of liken it to Facebook Marketplace.

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Um, where you request resource is or you like, for example, you search for use couch for your apartment, you know, and occasionally you submit your own data. Eso occasionally you reach out to the salary you say. Is that a Is that a big brown coffee stain that I see

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or you might decide to buy the couch, for example. But you can browse, and occasionally your

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you you send data

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and m q t. T. I think about this kind of a Twitter example where you can subscribe to messages for some topics. Like if I want to see what's happening a certain hashtag I'll just see the messages that happened with those with those hashtags.

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You can filter out the other messages that you just don't want in your feet.

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Eso I kind of use those those two examples to kind of help me as I understand how these things work.

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So here's another slide about how these kind of actually work.

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Uh, Coop is primarily oneto one protocol. It transfers state information between the client and the server. It provides, uh, inbuilt support for content, negotiation and discovery. It allows devices to probe each other to find ways to exchange information.

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And there's really no long term connections. It's all UDP

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and M Q. T T is really comprised of three components. A subscriber, ah, publisher and a broker.

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The publisher collects information and sends it to subscribers.

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The broker test publishers and subscribers, checking their authorization and and ensuring security.

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So M Q. T T clients make a long lived, outgoing TCP connection to the to a broker. It's really a one to many communication. Um, that's, um,

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kind of mediated by the brokers themselves,

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and the clients can also publish messages to a broker, or they can subscribe to a broker to receive certain messages.

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Messages are organized by topics. You can subscribe to some topics and published on others,

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and you receive the messages on the topics that you subscribed to. Eso It's kind of like that. The Twitter example.

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So this wraps up I ot communications.