Julio asks, could you please explain the hash function, how it works, and how to make the reverse process? A hash function cannot be reversed. In fact, that is the primary feature, if you like, of hash functions. And what a hash function is, is a mathematical manipulation, or an arithmetic manipulation. Basically, you take a series of data, or a stream of data, that's coming into the hash function, and you mix the bits with a particular recipe, and that's the hash algorithm. So, the SHA-256 algorithm uses a specific recipe to mix the bits, using various arithmetic manipulations at a binary level, such as, for example, shifting bits left or right, as well as exclusive or other mixing operations at a binary level. Now, all of this mixing together will take an arbitrary stream of data, of arbitrary length, and produce a fixed fingerprint for that stream of data that is 256 bits long. You cannot arrive back at the original data by reversing the hash function. That is a fundamental feature of hash functions. You also cannot predict what the hash function will produce, or deliberately produce a specific output for the hash function by tweaking your data. Effectively, every time you put data into a hash function, it produces what appears to be almost a random number. But it's a deterministic random, which means if you put the same data into the hash algorithm, you'll get the same result. You just can't predict what that result will be. Think of it a bit like in a visual term. Think of a billiard table, right? Take a billiard ball and hit it really hard, and have it bounce off the edges of the billiard table many, many times. Let's say a hundred times, because you hit it really, really hard, and it arrives at a specific spot. Now, if you started with the same billiard ball at the same location, and you hit it at exactly the same angle, with exactly the same force, it would always stop finally after a hundred bounces in the same position. But if you took a photo of the final position of the billiard ball, and you said, well, where was it when it started? It's impossible to work that backwards. So, while forwards, you can take the same billiard ball, hit it with the same strength at the same angle, and it will always end up in the same position, finally, at the end of bouncing it all across the table, when you look at the final position, you can't work backwards where it came from. Because it could have arrived at that position from a number of different angles. And what that means is, there is an almost infinite number of starting positions and different angles you can hit at, but there's a much smaller number of ending positions where that ball could be. And as a result, that function is almost compressing the information, and hash functions work very much the same. It's useful to make relations between hash functions and encryption, in that it is a form that is similar to encryption. But unlike encryption, which is reversible, otherwise, of course, it would be useful, hash functions also have this compression capability, because the end result is always 156 bits, no matter how much data you put in on the front end of hash function. And as a result, the amount of information encoded in the hash function can be smaller than the amount of information you put in. You cannot reverse hash functions, and they produce a number that appears to be random, even though it is actually deterministic and therefore would produce the same number every time. George asks, SHA-256 risks and applying two hashing functions on public keys. The Bitcoin protocol seems to have a strong dependency on the SHA-256 hashing algorithm. Although there is no known vulnerability of SHA-256 right now, what will be the effect and the risks for the protocol in case such an issue comes up? That's a great question, George. Any cryptographic function, including, of course, the SHA-256 hashing algorithm, will eventually become vulnerable in some way. And the reason for that is because computers get faster, but also mathematics advances, and algorithms get scrutinized in more and more ways in order to find weaknesses. So every single cryptographic algorithm that was strong 30 years ago is no longer strong enough. And as a result, has gradually been deprecated and replaced by more modern, stronger cryptographic algorithms with larger and larger key sizes in order to deal with this arms race between the strength of cryptographic algorithms and the strength of the computing infrastructure and the mathematical tricks used by people trying to break these cryptographic algorithms, including hashing. So it's not really an issue of whether a problem will be found or SHA-256 becomes too weak, but rather when it's naive to assume that this algorithm will survive forever, no algorithm survives forever. Now, it may be decades, it may be several decades, in fact, before SHA-256 has a meaningful compromise, and there are different categories of compromises when it comes to hashing algorithms. So a collision attack, for example, is one of them. Another is to select a specific hash and find a match. And another one is to select a specific plain text and modify it in order to find a specific hash. So there are different degrees of vulnerability that you can have in a hashing algorithm. Some are easier, some are harder. And it's unlikely that in the case of a hashing algorithm, you're going to have a vulnerability that immediately makes that hashing algorithm completely useless. Rather, what has happened in the past and is likely to happen with SHA-2 again, is that either a mathematical technique is discovered or a particular weakness that makes it slightly easier to attack the algorithm, meaning that it is theoretically possible at first with enormous computing power, and then eventually practically possible with enormous computing power, and then possible with even less computing power until eventually mainstream computers can break it. We saw that happen with algorithms such as MD5, for example, and the data encryption standard. An initial weakness was only exploitable in very narrow circumstances with enormous amounts of computing, and eventually nowadays you can break MD5 on your laptop in a reasonable amount of time quite easily. So we're not going to see SHA-256 go from completely secured to completely insecure. Rather, it's going to get eroded and become weaker over time, and that will require replacements. SHA-256 can be replaced in Bitcoin. There are a number of different places where it's used, and already there have been some upgrades. For example, SegWit changes the way addresses are computed for scripts, so making them stronger than they were before. With SegWit V0, a script is encoded as a double SHA-256 instead of a ripe MD-160, increasing the key space significantly in order to preempt potential attacks against pay-to script hash. So we could see other upgrades like that, we can see changes in algorithms, and for the most part the Bitcoin system can be upgraded fairly easily now with SegWit in ways that can address future impacts on cryptographic functions. However, one of the areas where this is more difficult is in mining itself. So we may see that it is much more difficult to change the mining algorithm of Bitcoin, and the reason for that is because you have all of this deployed equipment. However, if it becomes easier and easier to mine SHA-256, that's going to cause some changes in the difficulty of the algorithm, because miners will use the shortcuts to get greater profitability, which will drive the hash rate up and will of course then cause the difficulty to go up. In fact, that's already happened. Particular manipulation of the SHA-256 algorithm, called ASIC Boost, was implemented three years ago, and has led to a reduction in the amount of electricity needed to produce SHA-256 hashes, and therefore an increase in the efficiency of mining, and therefore an increase in the hash rate and difficulty of the Bitcoin system. That's exactly the kind of thing we'll see over time. So, in general, these things can be upgraded. The additional comment you made, George, which is, what is the purpose of double-hashing a public key to produce the address, and double-hashing it with two different algorithms, SHA-256 and then RIPE MD-160? Well, the first reason is to create a level of abstraction where what you're paying is a hash, not a public key. That gives us a lot of flexibility, including, as we've seen with the implementation of script hashes, the ability to pay to scripts that are more complicated than simply a public key. The other thing it does is it creates a degree of separation whereby, if the elliptic curve digital signature algorithm is found to be weak, but you don't have a public key and you have to crack a Bitcoin address, you have to crack two different hash algorithms before you get to cracking the elliptic curve, which creates a significant difficulty because hash algorithms and elliptic curve digital signature algorithms behave differently. One such example is in the use of quantum computers, which we'll address in one of the following questions. I hope that answered your questions, George.


It's useful to be able to work back and forth between the algebraic and the geometric. And so while we've found limits from graphs, we've found the algebraic from the geometric. It's also useful to go in the other direction and find the graphs from limits to find the geometric from the algebraic. So a key point to remember is that on the graph of y equals f of x, because y equals f of x, anything we know about f of x is also something that we know about y. And remember y is the vertical displacement of the point. In other words, on the graph of y equals f of x, y is going to tell you how far above or below the horizontal axis the point on the graph is located. For example, suppose I know some algebraic facts about f of x. Based on this, let's see if we can sketch a graph of y equals f of x over the interval between 2 and 4. Because it's the most familiar, it's probably best to start with the actual function values. Since y equals f of x, then if we know a function value, we also know the y value. So let's take a look at this. f of 2 is equal to 8. And what this tells us is that if x is equal to 2, y is equal to 8, and so the graph goes through the point 2, 8. We have another function value, f of 4 equals 5. So this also tells us a point on the graph. And in particular, it tells us that x equals 4, y equals 5 is a point on the graph. And so the graph also goes through that point. Again, since y equals f of x and the limit as x approaches 3 from below of f of x equals 5, then that says the limit as x approaches 3 from below of y is equal to 5. And we might read this as as x gets close to 3 from below, y gets close to 5. In other words, as we move right along the graph of y equals f of x, we approach the point 3, 5. There's one important caution here. This does not tell us anything about what happens at x equals 3. Remember, the value of f of x at x equals a is not relevant to the limit, and that also means the limit tells you nothing about the function value. So we don't actually know what happens at x equals 3, so we can't put a point at 3, 5. All we know is our graph is getting close to this point. Nevertheless, it's convenient to have a target here. So we'll do that by putting an open circle at the point 3, 5. And that indicates that this is not actually a point on the graph, but it's a place where the graph is moving towards. And then as x gets close to 3 from below, we have to make sure our graph approaches that point. And so our graph is going to look something like this. Similarly, the limit as x approaches 3 from above of f of x equals 7 means the limit as x approaches 3 from above of y is equal to 7. So as x gets close to 3 but stays above it, y gets close to 7. And so we approach the point 3, 7. And once again, we don't actually know whether there's a point there, so we'll draw an open circle to indicate no commitment over whether there is a point at that location. And as we move left on the graph, we should be approaching this point 3, 7. And this is what our graph should look like. Well, that was fun. Let's see what else we can do. So suppose I have some limits as x goes to infinity. Since y equals f of x, then limit as x goes to infinity of f of x equals 3 means limit as x goes to infinity of y is equal to 3. So as x goes to infinity, y goes to 3. And we can view this geometrically as follows. As we move way, way, way off to the right on the graph, our vertical coordinate gets close to 3. And this corresponds to having a horizontal asymptote of y equals 3. Likewise, the limit as x goes to minus infinity of f of x equals negative 3 says that as we go way, way, way off to the left, our vertical coordinate gets close to negative 3. And this corresponds to having a horizontal asymptote of y equals negative 3. Notice that we're also given the limit as x gets close to 5. But that limit is infinity. So it's worth remembering that when we say that an unqualified limit is some value, we also mean that the limit as we approach the value from below and the limit as we approach the value from above are the same. And so we know that the limit as x gets close to 5 of f of x being positive infinity means both that the limit as x approaches 5 from above is infinity and that the limit as x approaches 5 from below is positive infinity. Now, limit as x approaches 5 from above being positive infinity means that our y values get larger and larger as we approach x equals 5 from the right. And the limit as x approaches 5 from below of f of x being positive infinity means our y values get larger and larger as we approach x equals 5 from the left. And so this suggests that the graph has a vertical asymptote at x equals 5, where the y coordinates become unbounded as we get close to 5. And we can use this information to put together a sketch of our graph.


Welcome to the second bi-monthly or thereabouts edition of the DTNS Mailbag. This is the show where we take a lot of the feedback that we get from you over, let's say a month, and try to dissect it and get a little bit deeper into it. Joining me today, of course, is DTNS host Tom Merritt, but also former co-host of both of ours, IAZ Actor. Hey guys. Hey everybody. Looks out of here. Welcome IAZ. It's good to have you. Welcome to being here too. I'm welcome here. We're all welcoming each other. It's fine. That's great. It's like we never did this for several years. IAZ, I was asking you right before we started the broadcast how life was in New York. Sounds cold, little slushy, but spring is on the way. It is crazy inconsistent with the weather here. I mean, it's not as bad as New England was back when I lived there, but it makes me miss NorCal a little bit, just a tiny bit. Come back, come back. Working on it. Come back, come back. Well, I know IAZ is pressed for time because it is a Friday after all, and he's a very busy man. He's also three hours ahead. So we're gonna go ahead and jump into the first email that we got from James. This is referencing, this is probably one of the most popular email responses I've ever seen since I joined the show back in October. The uses for an old Raspberry Pi. New Raspberry Pi, pretty cheap, but hey, if you have an old one, what are you gonna do with it if you're not using it? James says, just thought I'd chime in and let you know, most likely others have already said this already, that the fine people over at Humble Bundle have a DIY electronics bundle of eBooks from Wiley. Six of those 14 are about the Raspberry Pi. The others are on Arduino, Beaglebone, General Electronics, and so on. Lot of great stuff in this bundle though, I'd suggest if somebody is going to pick it up, they do so for the $15 plus option, as they exploring Raspberry Pi or exploring Beaglebone books, both by Derek Malloy, both basically the same book, are beginner to deep dive in working with embedded Linux. He goes on to give us some links, I as knowing what I know from you because you're a tinkerer Raspberry Pi fan, also a person who puts together things from scratch and likes the hardware idea, has anything struck you as the best use of a Raspberry Pi that might be a paperweight otherwise? It's funny because Raspberry Pi's used to be great for like media streamers, Barokus, and Apple TVs, and fire TVs have gotten so advanced that you don't necessarily need anything like this as a media streamer anymore. I keep looking at it as a main machine, and there's questionable legality as to the ROMs. So if you're going to play a lot of video games like the NES Classic, those little devices or the SNES Classic, that's probably what I'd be using mine for. On top of that, there's something from MakePad. They let you build a tablet using a Raspberry Pi. It's meant for children to understand that they can build their own stuff. And for me, I've got a seven year old, and I want them to be aware that, you know, these things just don't show up magically all assembled. You could build this yourself. I really love the idea of using it as a learning tool, but otherwise it's more of a hobbyist device because so many devices can do so much of what the Raspberry Pi was meant to do. And it's kind of, I wanna say it's almost redundant, but it's really great as a learning tool. Yeah, I'm hoping that of all of these, and we even have some more to get to here, that all of these emails that may not only inspire Scott to do something with his Raspberry Pi, but maybe will help inspire other people to do cool stuff like that. I mean, having your kid make a tablet out of a Raspberry Pi, the whole conversation about screen time in your kids becomes so different if they've made the tablet themselves, right? Yeah, it's like, okay, so did you earn that time? Well, yeah, dad, I built it. It's like, all right, that's cool. What am I doing? I'm debugging, dad. All right, cool. Then you go in and disassemble it and be like, all right, got built again. Well, I mean, you know, the whole hobbyist aspect of it is like, if it's $35 or thereabouts, right? Then you have a little bit more room to play around with something than you would if you're not necessarily gonna ask your child to take apart an iPad. We'll get to that later. But this is not cost prohibitive for people who actually like trying things out. It's crazy cheap to do so many different things. I mean, look, it's a computer that costs a couple bucks. That's, I mean, years ago, that's unfathomable. And now it is easily done, like saying unfathomable. Speaking of Raspberry Pi has got another email from Bill. We got a lot of emails, can't get to them all, but thank you for everybody who wrote in with really, really good, really good tips for people who want to update their Raspberry Pi's or do something with Raspberry Pi's that are sitting around. Bill is from Huntsville, Alabama and says, recently a reference was made about Raspberry Pi computers and what to do. I bought my first one in 2015. Used that one to set up a J-Bod NAS. I have five USB drives connected to an 18 terabyte capacity that I use for backup. I keep that system in my basement. My second project was to make a digital clock. I have a third connected to a seven inch screen, keyboard, mouse and speakers kind of speaks to the whole tablet idea. The Raspberry Pi has a few limitations. There are no competitors that address some of those limitations. They include that it only has USB two ports and a 100 megabyte ethernet port. I just received delivery of an SBC called the Rock64, which I paid 48 for. That includes a power adapter, case and shipping. One month between the order and delivery from China, the Rock64 has gigabit ethernet, both USB two and USB three ports, but no built-in wifi. So it sounds like there are a lot of really fun solutions that people are coming up with, but there are also limitations based on the price. Plus just a shout out to Bill Burlingame. He's been a listener of DTNS from the beginning. He's been a techie for decades. I love his stories because he'll tell me things, he'll write in and tell us things about, when he was first working in the 60s or 70s and how things worked, or even I think before, I don't mean to date you, Bill. And then we get emails like this, like, oh, well, I've got three Raspberry Pies and this is what I'm doing.  I'm looking at the specs on Rock64. I actually output 4K 60p video. I don't know what the newest Raspberry Pi does. I'll say that. So that sounds pretty interesting. I don't know what you'd want to drive with this. You can do a lot, just see a giant widget machine which is really old and silly to think about. Yeah, and just fun stuff to tool around with. These are some great ideas for projects right here. Got another email from Cameron. He lives in Adelaide, Australia. And this is regarding our discussion that spanned a few days this week about the idea of social networks employing humans to basically make sense of what AI cannot and that includes disturbing content. So content that should be banned, that maybe has been flagged by a machine but a human needs to say, yes, yes, this is bad. And the sort of traumatic implications of being employed in a job like that as a contractor, as a staff member, whatever. So Cameron says, few things stand out to me. Number one, hopefully this is just the busy part with these tech companies to skirt significantly the content creation to a more manageable level. You often talk about podcasting. Other noble content is having the cycle but I don't think we've considered the effect in this kind of disturbing content. Number two, although there are many jobs with this kind of exposure, I guess it's new for a big tech company. Also a little bit of an odd mix when you're talking about white collar, batch work, load desktop type work, certainly you could imagine how much more horrible YouTube could be viewed in eight hours. The whole story from the other day was that they were going to make the cap on any contractor who is doing this at four hours a day, right? Eight hours, twice as bad as four. Cameron says also maybe a little isolating as compared to say the police or a dictator and his colleagues. All right, we'll end there. Number three, seems like the maturity of the internet to me. Now they need content to be policed. We're learning how that was all going to work between humans and AI. Ayaz, have you been following the story and what's your gut tell ya? If I understand the story correctly, I was thinking about when YouTube had all those disturbing videos for children. Is that what we're talking about? Is it something similar? Well basically what they're saying is they're limiting the amount of time that the moderators they're hiring to search or to review for disturbing images have to spend because they're spending a lot of time looking at disturbing images. So they're saying only four hours at a time on that job.  This is a real problem because look, algorithms can't suss this stuff out yet. It's really hard to tell between like a medical procedure that's being viewed or a scientific explanation of something versus something that is completely just vile. There's a huge difference as to what defines these particular kinds of content. So to protect the employees who are viewing these images, that's definitely smart. And I'm sure that engineers are hard to work figuring out a way that they can automate this because the hope is one day it's going to be automated and no one's got to worry about this but there's always going to be flags brought up. Well, and that's one of the most fascinating things that I find about this is AI is not perfect, right? It's doing a lot of stuff that it didn't used to do before and taking humans out of the equation but with mixed results and lots of room for improvement. So when I hear from Facebook, it's like, well, we're trying to make the news feed more relevant to give you stories that you might like or that sort of thing. It's like, okay, that's fine but if there's actual humans that have to look at disturbing content to the point where they could be put in a PTSD situation that's extremely harmful, perhaps for the rest of their life, that's what I want AI to figure out. I don't care about all this other BS. Like that's actually what we should be figuring out so that people don't have to do this. Well, yeah, there's a couple of further thoughts, evolving thoughts on this matter. One is, four hours sounds like a lot to me if it's four hours of disturbing images. You have to remember that they're reviewing images, not every one of them is gonna be disturbing. So maybe that four hours isn't as bad as I thought because it's not constant, right? They're reviewing things and some of the things they'll look at and say, oh, that's not that bad. I don't mean to minimize it. I'm just saying, well, at first I was like, wow, four hours is still a lot. Second, people wanna say, AI will never get good at this. Other people say, AI can do all of this. And the fact is we're slowly seeing computers get better at this. Algorithm is not a bad word. Machine learning is not a hoax, but it's not perfect. I mean, I compare it to voice recognition. For a long time, we had voice recognition that just wasn't that good. I was using voice recognition on my Windows 3.1 machine in 1994 and it was very basic and people laughed at it and said, well, that'll never be able to do X, Y, and Z. Well, here we are with Amazon Echoes and Google Homes and they're really good at recognition. Now our complaint is, well, they don't understand the semantics of what I say. And that's what we're talking about, like seeing these things get better and better to the point where, yes, I think what you're hoping for, Sarah, will one day be possible where 99.9% of the things we don't want to show up can be identified, it's a matter of time and I don't know how much time that's gonna take. Yeah, I know, it's, the complications of all of this are vast and I won't pretend to. We've gotten quite a few emails, especially from people who've served in the military, our law enforcement and been exposed to a lot of this stuff and they have much better ideas of what kind of content we're even talking about. For me, I'm like, well, I can imagine what it is and it seems really bad, but if I was being exposed to that for four hours a day, I don't know. I don't know if I could handle it and I'm not sure that a lot of the people who might take a job because they need money are equipped to handle that as well. And this is sort of lifetime trauma stuff that should not be minimized. We actually got another email from Brian about the same subject, not to be too much of a downer here, but hey, we got a lot of emails about this. Says, when I heard the story about human operators being exposed to abjectional content on YouTube, I thought of radiation jumpers, if you don't know what that is, generally unskilled laborers who do the least desirable jobs in the nuclear industry in the most extreme cases, they enter disaster areas. Fukushima, for example, to perform emergency tasks under heavy radiation for up to an hour at a time. So again, this is sort of a quantitative thing that somebody is putting a cap on here. Once they near what's considered unacceptable cumulative dose of radiation, then they have to get out of there. They shouldn't work anymore where they're exposed to radiation. The problem is that an acceptable dose is subject to interpretation. And that also workers in less dramatic positions, for example, in the trekking industry would meet their lifetime exposure in one location and then move on to another. This sounds horrifying. That's sorry, I just got really silent on it. Something like, this is a terrible thing.  And sometimes people need to take whatever jobs are out there and they have to view, and if they are qualified to view abjectional content, which is a weird thing to say, I don't know how to think about it. There's probably gonna be a lot of psychological evaluations of these people on a regular basis because not thinking like a lawyer. If you're going to have a giant corporation that's worth billions of dollars, they don't wanna be associated with anybody who is permanently traumatized or does something awful or evil or something close to what they've watched at their job site. They don't want that kind of thing going out. So hopefully the companies or corporations are being responsible enough to keep tabs on these viewers of content. Yeah, YouTube is a victim of their own success here.  They let you have their product for free. They let you use your own domain name. They stay out of it. YouTube wanted to be more involved. They wanted to sell the ads. They wanna, you know, and so because of that, they became attractive for people who wanted to game that system sometimes with evil intent. You know, I probably am closer to this than I was a few months ago just because I just went through picking new health insurance, you know, and it's sort of like physical, mental.  But I do feel like this is a very good case. And, you know, again, this is in very general terms, but a very good case for understanding, hey, if somebody's at a nuclear site and they get exposed to too much radiation and we've all determined that, like, after a certain point, that's really bad.  Mental health can and should be treated more increasingly in the same way. Yeah. No, that's a really good point. There should be better metrics to understand when someone is at risk of a major problem, right? And the ability to evaluate that. All right. Let's move on to something a little bit more lighthearted. This comes from Robert. He said he sent this from his Commodore VIC-20. I don't think he was sending this from a VIC-20. Come on. I had to look that up, so. Oh, it's called a VIC-20. Oh, yeah. No, I had a Commodore 64. The VIC-20 was the predecessor of the Commodore 64, circa 1980. Why would he say that in email signature? It's for kicks. Just for fun? Unless he's actually hacked his VIC-20 to access the internet. I don't want to undersell you, Robert. Maybe you did it.  And that way we'll know that you're for real. But this is actually just sort of a silly thing we were talking about the other day. We were talking about the metric system versus the imperial system that we use in the US and also that. I was advocating for Pi Day. I was saying 314 is acceptable because the month should come before the day. I don't like that the year is at the end. The year should be first in the month of the day. That's reverse order. But depending on where you are in the world, I, most of the time, there's day, month, year, because that actually makes more sense, right? No. A smallest, no. You want to tell us the European Union, how you feel about it? Yes, this is one of the times that that was what that whole conversation was about. It's like, yeah, I'm way into the metric system, Europe, but you got your dates all messed up. It should be year, then month, then day, because it's in descending order and then it sorts really nicely. I, as I know you do a lot of podcasts, is this something that you think about in your daily metadata life? You know, I actually, I write it this way. I actually did the year, then the month, then the date, because when I need to sort it for files, that's a lot easier because the date created thing changes for some reason. I'm like, that shouldn't be happening. Last updated could mean nothing. So for file name, I actually do use this. It's weird because I'll end up writing it on things like checks, which doesn't make any sense, at least in the US. Anyway, we should read Robert's email because it supports my point. Well, but Robert says, year, year, month, month, day, day is also known as a DOD date. I assume he means Department of Defense and in the service, we use that almost exclusively. Thank you. Thank you. Exactly. Fine, fine. When lives are on the line, you use year, month, date. When our boys need it. Thanks, Robert. Always good to hear that I'm doing things wrong. We got another email from Yaru who comes from Malaysia and this is in regards to another very lively topic we had on DTNS, which is right to repair. Meaning that several US states, more than several, 18, if my numbers are correct, have introduced bills to force companies to allow civilians, consumers, to at least have access to how to repair something themselves if they can get those parts themselves. So for, you know, you could use Apple as an example. You know, if my screen is shattered, well, I mean, it's expensive for Apple to fix that for me, but that's kind of my only option, right? So one would think that companies that make a lot of money on repairs would not want this bill to go through, but again, going back to, you know, the tinkers of the world and people who say like, hey, if I can do it myself and I can not brick my phone, I would like to do that as well. And this doesn't even apply just exclusively to smartphones.  Anyway, Yaru says, I have an iPhone 7 Plus. Battery works fine for the most part, but it's been more than a year. I was thinking I didn't change. Take advantage of Apple's new official discounted price for batteries due to their recent battery gate scandal. But Apple told me it would take five to seven days to get that new battery. And no, that doesn't include shipping to location that involves me actually going to the center, dropping the phone off, picking it up after that period of time. By contrast, a third-party repair shop that's in my vicinity, I assume, can get it done in 30 minutes, maybe an hour. I know this because I've done so with my previous phone, and that was an iPhone 6 Plus just last year. They told me they could do it for a cheaper price. Phone still works well as being used by a family member at the moment. Modern smartphones have more complex battery systems, but nothing that would justify that length of downtime. He goes on to explain a little bit more about his point, but yeah, I agree. You know, I think for a lot of folks, it's sort of like, yeah, the convenience of just not having to open up a computer, whatever that computer is, whether it's a mobile device or something larger, for a lot of people, myself included, and it's worth it probably. But the time spent waiting for something, especially if you're going through the proper channels, that's the prohibitive part. Yeah, it's not just cost, it's speed, absolutely. It also sounds like since Apple has tons and tons of phones that it sold, and is probably dealing with lots and lots of phones, they have just an increased volume, and the time is just a function of amount. So just because some third-party shop that's on the corner, they get, let's say, 50 iPhones a day, sure they can run and do this quickly. Versus Apple, they're probably getting more than that. There's a good chance, and this is just wild speculation on numbers there. So I know with my iPhone 6, I got its battery replaced, it took about six hours, and that was weird, because I'm like, well, you're right here, how long is this gonna take? And I understand the feeling of not having a phone and that interim, that seems like, if it's five to seven days, I almost feel like they should give you a loaner.  Cool rental car for a few days. Something that at least you can use, and it's insured like crazy. So when you break it, it's fine. But I just think it's a volume issue right now, especially since Apple was discounting heavily. I think it's $39.99 or $29.99, $29.99. That price is so much cheaper that even though my phone could survive another year, I'm like, I'll just take it in now, and take this for $30. Well, I think that the sort of underlying issue that a company that wants you to pay a higher fee so that they do it themselves, is a lot like an auto manufacturer, right? Like my car, if I go to a shop that's confirmed, is like a Mercedes shop.  But that's really in an attempt to get as much money out of people as possible. So if you are a company who is forced to give people the blueprint to put their own battery into a phone that they know how to do, not everybody's gonna know how to do that. Some people are gonna get it wrong, but to sort of make it seem like, oh, as the official manufacturer and company that gave you this phone in the first place, and I keep using phone as an example, we're the only people who can fix it is, well, that's just not true. Yeah, it's, we, I feel like there's lots of arguments that have been solved in previous industries going on around this. A lot of the arguments have to do with like, well, how can you trust third parties? And I certainly can't repair a phone. Why should I have the right? And if you look at washing machines, refrigerators, we have a pretty settled system about what a manufacturer is required to make available schematics-wise and parts-wise, and what it's not, and that system seems to work fairly well. There are 30-party repair places and there are warranty repairs and there's even like warranty services, like American Home Repair and stuff like that. Maybe that part needs some work sometimes, but there doesn't seem to be any controversy over the right to repair your refrigerator or the right to repair your car. So I feel like, yes, Apple, Samsung, HTC, they should have the right to decide what they do with the things they sell, but we have some really settled ways of going about it with other appliances. Maybe we should just apply that to these. And these companies can also probably game the system. Let's say that every state decides to pass these right to repair things. I'm sure Apple or Samsung could be like, hey, look, if you see certified by Apple or certified by Samsung to meet our standards or that there's a union of some kind that says, hey, these are the standards that they make it to, that could give you the option of, which ones are more trustworthy? Like if you go to your mechanics, are you ASA certified or are you not? So like I could see that becoming the new reality. There are already Apple certified shops, right? Like that's already a program that exists. It wouldn't be hard to extend it.  So like, there you go. Also, I mean, if you can pair it to a car, it's like, eh, things happen with cars all the time, but like, compare it to a dishwasher. I mean, I actually just had to have my dishwasher replaced, but it was like a million years old in my apartment. These are not sort of like the yearly cycles that a lot of electronics companies are pushing. And that's another added factor into this, right? It's like, if you buy a dishwasher for 20 years and one thing goes wrong, 10 years into it, a lot of things happen. But if you're a company that's pushing people to upgrade, especially if there's something wrong with their device that they kind of like, ugh, you know, can't afford to fix or don't know how to fix, then there's that, there lies the rub. I think designed obsolescence is well over exaggerated to conspiracy theory proportions. But what is true is that these companies essentially see the market and that we, maybe we're taking three years to replace a phone instead of two years now, but it's fast. And they don't want to have to deal with third-party repairs because it would change the system. Some of that change might mean slower sales and they wouldn't like that, but that's not the only reason. They've got a whole system based on the fact that people just naturally want to upgrade these things faster. And if they can control, especially somebody like Apple, if they can control that repair cycle, they like it better. I has anything to add before we wrap up this second bi-monthly, whatever we're calling it, mailbag episode. Far from the clunky title? No, I think I'm good. What, you're good? No? I'm good. I think I'll say what I wanted to say. Well, thank you very much for being here before we let you go, because I know you've got a world Friday ahead of you. You get a lot of feedback from your fans as well for a lot of the work that you do at CNET and personally. Is there anything that has kind of resonated with you recently as, wow, this is a really hot topic that a lot of people in the tech community want to talk about and hear more about? I am completely unprepared for that question, so I'm just not until I remember anything that has happened recently. No, I'm just like, when it comes to tech stuff, I end up getting so much more feedback on geeky news. So like the Avengers movie trailer just dropped today, and so that's more about what people are excited about and the fact that there was like an announcement yesterday for a trailer. Well, that fits. It's strange that there's essentially a news release for a trailer, which is an ad for a movie. It's like, when does it stop? I assume we're gonna get a pre-notice about a notice, about a notice. So that's just a weird aside right there. Good, Avengers. Keep writing to Aya's about your thoughts on the new adventures trailer. I'm psyched for it. Speaking of, where can folks learn more about what you do? And if you like, where can they talk to you about their feedback? Twitter's always the best place. If you write to me, I will write back. It might not be right away, but I will reply you back. Twitter.com slash I-Y-A-Z, that's me. And no, that's me part, but at Aya's. That is your name. It's my name still. So the rapper is at Aya's live. He is a very cool dude, but I don't sing. That's the only thing I gotta tell you there. Oh, there is a person who raps named Aya's who's at Aya's live. He's at Aya's live. I'm just at Aya's. Gosh, I forgot about Aya's live. He's still there and I keep getting like, Oh yeah, yeah, no. TVT's all the time and I'm like, yeah, I don't remember singing that. Anyway, go to CNET.com as well. You'll see my videos constantly because they're there and I'm there. And they, for some reason, keep promoting my material. So that's a great place to get a hold of me and topics to discuss. Well, again, thank you for being part of this show. It's always nice to hang out. We're missing Jason Howell, but otherwise gang's all back together. Tom Merritt, thank you as well. Anything that has resonated with you in the mailbag that we might tackle in the next episode. You know, that's a great question. This right to repair stuff was awesome. And I have really enjoyed going through those emails. I've been forwarding them to Scott Johnson. I'm talking to Scott about what he wants to do with all these emails. Maybe we'll get Scott on the show, on the main show to talk about if any of them have inspired him. Little Raspberry Pi, how to? Yeah, yeah. Yeah, yeah. Raspberry Pi meal. Sure. Well, again, the idea behind mailbag is that as DTNS grows and our community grows and our feedback grows as well, it is excellent. We don't have time to put everything into every show as everyone knows. But this is going to be an idea of, let's put all this feedback together and talk about stuff on packet a little bit more. Especially the kinds of emails that we get from people where we go, okay, this definitely struck a nerve. Let's give this a little bit more time as bonus content that we don't do on the regular show. One of the things I would love is if people want to write in specifically for the mailbag a question that they'd like others in the audience to answer. I mean, the website says helping each other understand and this is one of the venues for that. So send us a question where you're like, I need to help with this. We'll pitch it out to the smartest audience in the world and see if we can help you out. Exactly. All right, well, lots of stuff to think about this weekend. Again, feedback at dailytechnewshow.com is the easiest way to get a hold of us. You have other options, but hey, that is the mailbag itself. Thank you to everybody for being with us and please let us know what you'd like to see the mailbag evolve into. We are, you know, it's a blank slate for the most part. So feedback is the way that this evolves and becomes greater. Have a wonderful weekend.


Tom here from Lauren systems and this is the unify redundant power system Well, this is a disassembled one because hey why not start with not an unboxing but a disassembling and This is an interesting take on redundant power supplies for well not just Switches but also other devices some of the ubiquity routing equipment some of the ubiquity nvr equipment now supports this and I It's an interesting approach We'll get into the details later in a video about you know why they may have done it this way But I kind of think it's an interesting approach. There are a couple things. I will get to as well that are well I don't know what design flaws, but different design choices They made that maybe can be changed and I'll break down those use cases later before we drive into all that let's first If you'd like to learn more about me or my company head over to Lawrence systems comm if you'd like to hire short project There's a hires button right at the top if you want to support this channel in other ways There's affiliate links down below to get you deals and discounts on products and services We talk about on this channel including a link to our patreon if you'd like to become a patreon supporter We also have a swag store where you can get shirts and other items that are for sale and that changes from time to time What's available and what's not so go ahead and check that out frequently and finally our forums If you'd like to have a more in-depth discussion about this video suggestions for new videos or just reach out Say hi and talk tech our forums are a great place for that all right now back to the content We'll start here at the product page the unified smart power redundant power system model USP RPS is a proprietary redundant power system designed to protect up to six unified smart power Supported devices and I imagine they're gonna be doing more devices in the future on that now a couple things of note note It's called a USP not a UPS There are no batteries in this and I think that is well at least my initial impression was maybe it was gonna have some Type of a battery system in here, but it does not the concept and idea of how this is supposed to work Is any device that supports the redundant power you would purchase those and you would buy them at You know essentially a lower cost as the concept that unify has because they don't put redundant power supplies in but for people who need it you buy this which is a Larger capital expense with an MSRP of 399, but now it can provide six devices a redundant power supply So different concepts essentially in ways of power delivery Right or wrong you can make the argument Why don't they just offer a different model with dual power supply versus not it? Maybe it's just a way to simplify the product line either way It does work and we are going to show how it works to do some testing with it now It does have these six connectors on the back along with three fans one power input and These 24 pin connectors is where is the actual connector that's on there and if you're thinking hey 24 pin connector What does that cable actually look like one? It's pretty hefty beefy cable to and in case you're wondering a 24 pin. Where have you seen a cable that looks like that? I think this would break it if we actually plugged it in but yes, it's the same pinout Well pinout as in the way the little edge connectors are it's an ATX Adapter cable which almost makes me wonder could you use just a ATX cable to extend from device to vice rather than the Proprietary unify cable. I don't know if there's any electronics in here and I haven't Wanted to potentially damage the product by trying it with a Cable I could always I guess check the pinouts and see if they're all just one-to-one or if there's any type of electronics in between I don't know. Maybe I'll do that in the later date if there's some demand for it But for most part I think if you're buying equipment and you want redundant power You're doing it and you don't mind buying these cables which are like $29 MSRP right now Which means we'll probably get a little bit cheaper over time or be able to find a deal on them But I did find it interesting it is an ATX connector and it's a very well made heavy gauge cable This doesn't feel at all cheap. It feels like you're here in metal clink there So I like that they made these you know really solid like I feel comfortable using them I don't have any Qualms about it going well. Do they use thinner wire everything about that feels quality matter of fact The molded edges on there are important because I will tell you It it is pretty solid on there, but one of the other challenges we realized There's a some effort putting in to snap these in they are not coming out matter of fact. This is heavy and If that doesn't give you an idea like these are solidly in there matter of fact you're not hard to remove But there's some effort involved in it, so they're not gonna flop out They're not gonna if you move a switch around or have to slide something around in your rack They're not gonna fall out on you and the durability with this heavy gauge coating and everything on it Yeah, I will say that they did a nice job on product quality in terms of that I did remove this plenum right here and so I wanted to expose the way the power supplies are set up and it's Kind of interesting because it's like there's two power supplies and I'm just guessing it's for different types of power delivery We have this one here and then this one here now This has a lot of different options on here and I noticed the way it's soldered to the board here We have like a whole different series my guess is be for some of the different power delivery Options and then we have this one here, which is your like a heavier gauge rail and all of this is encapsulated. They got the Goo in here. It's kind of hard to see, but it's eventually it's like a hot glue type sealant But it's to keep things really tight so nothing wobbles nothing can wiggle around in there The components can't come loose. So they're encapsulated really really well in here now with all that being said one notable thing is by removing this I've created a bit of a challenge for myself because of the wiring the wires are really tight between this So if you decide to do this, um, I'm gonna have there's gonna be a pause in the video here We jump to Tom after he reassembles this to get the wires put around there also of note in the plenum is A little divider so only one fan is needed for one power supply and the other two fans are for the other power supply and divider But other than that all the electronics in here look solid. Oh, and as chris noted in his video You've probably seen that chris from crosstalk did a video on this as well Uh, they put a network cable in here So we could we just go from the network interface board here to the network here with a Standard a little network cable. Uh, oh the interesting design choice to do that So there is that just so usb in here. I don't know what it's for maybe some type of specialized firmware update Um, and then they have this little power cable that's undoubtedly for the lights that are on the front because the network cable on the The network for this is right on the Front of this device. So it also does have a display We'll get to that once it's booted up and turned on and show you how the display works on it All right now i'm gonna reassemble all this All right, the device is reassembled no magic smoke came out, which is great It wasn't too hard to put that plumb back in I thought it'd be harder than it was with the wires But nonetheless the thing I'll note at first and by the way, there's two devices running right now This is the unify nvr, which also this is the new forebay one. I'm doing a review on it soon That's coming and it also has the connector to do the redundant power supply So I figured I'd test it with something more than just a switch We know it does switches it does the some of the pro switches I'm sure they're gonna have more of their switching line that comes out And of course the I believe the dream machine pro has support for it And we'll probably see more products come out for it But why not try an nvr? And this is where the use case comes interesting from unify standpoint because well Not everyone wants a more expensive nvr that has two power supplies in it But with this now you can have two power supplies for your nvr As well as maybe some of the other equipment that you need So like I said, it's an interesting Approach to it because of the number of devices that it can support But you see the heavy cable plugged in there And let's start with the screen on the front and talk about the features of the screen Because it's kind of I like that that they've added these so I can you know walk up to something in Iraq and look at it But let's take a look at this So this is that same touch screen that we've seen on other unify devices I'm just modified to show the ethernet port so we can see that it's got a connection there We can look at the rps ports so instead of looking at ports in terms of you know, whether or not your Link lights and things like that that you'll see on a Switch they've just modified it to talk about the rps connections So there's one device connected and it's delivering no wattage and all the ones are disconnected now if we unplug The nvr it should take a second here and It now delivering power so it updates in real time and we'll show that again inside the unify But it's pretty nice little, you know touch screen on there They're really intuitive. I this is a one of the features. I think it's just really cool about this Also being able to get information like hey, what's the ip address on here? What's the status on this thing? How long is the uptime? These are just really great features this screen I only thing I wish is that it was on the nvr, but I'll talk about that in my other review Now as far as adopting or setting this up It's like any other unify device if it's on the local network. It can show up There's you know ways you can set in form and I'll point it to something external But it just goes into the standard unify control plane And did nomenclature is similar in terms of the way they label the ports They have a little description below and we have just green to say that it's plugged in but not delivering power And white is disabled now It does also follow like your standard I was a switch with the port configuration options where you can name it and we can say unify nvr And hit apply and the other option in here is to save or auto So it doesn't really have any details in terms of the way you deliver power to it or anything else But I do really like that you can label the ports It would be kind of cool because it does realize when you mouse over what's plugged into it Uh, but it doesn't auto label like that's a feature that I think would be kind of neat Is to say pull all the labels of everything I plugged in and just put them in there So I don't have to do the labeling myself So I'll that would be neat. Um, maybe that's a simple firmware update that they do But you can label them yourself. So not a big deal. I won't dwell on that Other than that it does have stats cpu memory. Just they pulled the same type of menus that you're used to seeing you can open terminal and That works too. So you can We use it and ssh into it using the standard, you know, unify terminal But of course what you really want to know is what happens when there's a power failure So we'll show you right here that I have my hand on it. I'm going to go and unplug our Unify nvr here and actually switch to the screen here and Now we have lost power. Well, not exactly if you notice The unify nvr is quiet. So you didn't hear any noise change, but it's still on I still see a blue light here Now there is a Instant that you know on the screen now it's going to show that it's delivering power on the little front panel screen And there seems to be a little bit longer of a delay Maybe about 30 40 seconds before it shows here and I get the notice But that's you know, uh, it probably just doesn't have The polling frequency that you have with some of the other devices that I think update a little bit faster But nonetheless, it does work exactly as expected where this will switch over It has kept the device on and then a notice will pop up within so many seconds And of course you can have these alerts sent to you to let you know that it's in power delivery mode Now this is where I did reach out to unify to confirm that this behavior is normal And what I mean by that is right now is powering this and it will You know, it's got the notice coming up and lets you know. Hey, we're delivering power We've you know, this device is you know lost power for whatever reason It doesn't know why it lost power doesn't know that I pulled the plug out It doesn't know if the power supply failed But what is important to know that when this occurs this device is running until I power off this device or I reboot this device and why is that important? Well, here's an interesting scenario that you may run into if this power supply did indeed go bad That happens and we know we need a replacement if in any time in between you like to sell this out of the rack You wanted to reboot it and you're like, yeah, I guess the power supply is bad I see some type of part on there and I want to replace it But hey, I can just run it off of this in the meantime, but you can't So as long as this stays up It works But and this is for switches as well and for the nvr and any other devices we've tested with this And like I said, this is confirmed from unify reached out to them on what it will not do Is if we power cycle matter of fact, if we power cycle the unify smart power device It won't power this back up either. So if I were to lose power on this This stops Powering up because it at least initially has to have a power supply on and it will take over But it will not boot up a device and they said this is kind of a safety issue So if the devices are off, they don't want to start forcing power into them, which I it's an interesting case. It does save you from fail over, but it doesn't save you from If you had a massive power outage and everything comes back on and in that on process I know these are edge cases, but I just want to make sure people are aware of the product And how it works that if that power supply were to surge and then go bad on this device This can't work just as a power supply from Zero to boot. It has to be on and lose power from its main power for this to take over But not Boot up for or act as a supplemental power supply in the meantime while you're waiting for replacement if you reboot it. So It works perfectly fine for what we're doing right here. As a matter of fact, I can show you You know, we have the here we have an alert that popped up and it lets us know that we lost power on this particular device So it says rpcs delivering power on port one connected device that has internal power supply failure Or loss of ac so it gives you the notice and like I said, you can have those notices sent to you You see the little power delivery button right here. It tells you what it's delivering how many watts, etc So all that works and we can go here and plug it back in and it works Of note now nvr. You can see a little light blinking in the back here and it's on In fact, we'll do I got a power brick right here.  It did though Restart this device so in that instance if there's a power flicker It seems to still be able to power up this device and start it up So I found that interesting so as long as it doesn't completely shut down And from the loss of power and it's just going to vary because it doesn't have batteries in it But there are at least some power holdings it has uh through the capacitors that are in it So if there's a power flicker it seems to Survive it like the This did reboot this and did come back on but as long as this didn't get completely shut down And because it was in the state of delivering power to this that flicker didn't do it So this is a good thing because if you have a flicker Some type of small voltage spike, which hopefully you have all your rack equipment protected properly This won't be an issue But in the event that a small flicker did that and it took out the power supply to this But this didn't actually turn off then now we have proper failover And it's going to still keep working and powering it because this is now as you can see the light blinking over here Boot it back up and we can just go back to delivering power to it like normal And uh plug this back in and away we go no big deal. So let's uh, yeah head it upside down So now this will do that and now this notice will go away So overall I think the device is interesting is an interesting approach to doing this And when you think about building out a Unify rack instead of having to buy you know each device with redundant power It's you know Going to be a cost effective measure to buy this and have it power all the devices from unify standpoint Someone could just argue. Well, you know make two different models and I get that But that would mean each model they make would have to have either two different skews one with dual power supplies One not and from their product line standpoint You're like that's easier to put this little adapter on there and it leaves more room in the device Because of it. So um, like I said, you know, are you both ways for that? This is the way unify shows to approach it. I think it's kind of neat. We do like it as a device. So if you have Um, you know the need for that The downside is I mean it's a 400 dollar msrp with 29 dollar cables So it's not going to be inexpensive to build this out and then from a cable management standpoint As much as I said, these are awesome. They're heavy gauge and I feel they're super solid I could probably pick up both of these devices by it I will also say that now I have that many more cables behind my Equipment that has to go up and stack and yeah, that's that could create its own challenges Related to that because of the heavy gauge cable. So a lot of thoughts on it Um, it's pretty neat, but from the nvr standpoint too, uh, that sometimes is where mission critical comes in I really like that the uh New unify nvr and yes for those asking the review will be coming soon on it That's why I'm actively testing it including the things I'm doing like that to make sure it provides power delivery properly. Thanks And thank you for making it to the end of the video If you like this video, please give it a thumbs up If you'd like to see more content from the channel hit the subscribe button and hit the bell icon If you like youtube to notify you when new videos come out If you'd like to hire us head over to laurance systems.com fill out our contact page And let us know what we can help you with and what projects you'd like us to work together on If you want to carry on the discussion head over to forums.laurance systems.com Where we can carry on the discussion about this video other videos or other tech topics in general Even suggestions for new videos. They're accepted right there on our forums, which are free Also, if you like to help the channel in other ways head over to our affiliate page We have a lot of great tech offers for you. And once again, thanks for watching and see you next time


Okay, just waiting for the lecture to start.  So we are looking at Romans chapter 10 verses 14 to 21, Romans 10, 14 to 21. So what the Apostle Paul has taken us through is he's pointed us, he's highlighted a passage from the Old Testament and shown how that applies to us, that the principle applies to us in the New Testament, emphasizing that the commandment has been replaced with the person of Christ.  And in the New Testament, it's the message of Christ that we keep in our hearts and we proclaim with our mouths. And then he says, verses 11 to 13, hey, this message is for everybody because anyone can call on the name of the Lord and be saved. Anyone can do this. Anyone can believe in their heart and acknowledge Jesus Christ with their mouth, and they will be saved and experience who Christ is in their lives. And it's for whoever who will call on the name of the Lord. And you know, he's continuing throughout this chapter to quote from the Old Testament. So then he, verse 14, he says, but you know, there is a problem. People cannot call on someone if they haven't believed in him and they cannot believe if they haven't heard because he says to us in verse 17, you know, faith comes by hearing the message of Christ, the faith comes by hearing the word of God. You've got to hear the message, only then you can believe. So how can you believe if you haven't heard? And how can you hear without a preacher? Somebody's got to go and tell them. And how will they preach unless they are sent to verse 15? That means somebody's got to say go, you know, send them out. And so, you know, verses 14 and 15 are classic texts used to encourage people for missions. You know, look, we have to go out and proclaim the gospel, have to go out and share the gospel because people cannot believe in someone they've not heard. They cannot hear without a preacher and they cannot go preach unless they are sent.  And he's quoting, you know, from Isaiah, and this is in verse 15, he says, you know, because even Isaiah said, how beautiful are the feet of those who preach the gospel. But verse 16, he says, but of course, you know, not all have obeyed the gospel just because you go and preach doesn't mean they will respond to it or say yes to the gospel because Isaiah himself said, you know, who has believed our report is questioned. In other words, what's implied is not everybody who hears will believe. And so Paul is very aware of that. But still our responsibility is to go and preach. We have to go and preach because it comes by hearing the message. But not everybody who hears the message is going to believe is what Paul is telling us there in verses 14 to 17. And then he kind of goes through this, you know, he asks these, once again, these rhetorical questions concerning Israel, he says, you know, but haven't all of them heard? This is verse 18. Haven't all of them heard? He says, yeah. You know, again, he's quoting from the old testaments. The psalm has already said that, you know, the word has gone out to the ends of the earth, at which people have gone out with the message. But verse 19, another question, but didn't Israel know this? I mean, didn't Israel know this truth, this gospel? He said, yes. Israel already knew this. But and now verse 19 and 20, Paul begins to set the stage for what is coming up in chapter 11, which is that God has taken the gospel out to the ends of the world. He's taken the message out to the Gentiles in order to provoke Israel, in order to provoke the Jews or, you know, like, wake them up to the truth. So it's very interesting. The truth was given to the Jews, went out from the Jews to the Gentiles, and now God is using the Gentiles to awaken the Jews. He uses the word provoke, but you can understand it in the sense of awaken them to the truth, the very truth that actually went out from the Jews to the Gentiles. So that's what he says here in verse 19. He says, hey, Moses said already, I will provoke you to those, to jealousy, jealousy. But those were not a nation, but those are not a people. That means I'll use the Gentiles to stir you up in, you know, towards God, of course. And verse 20, he quotes us as saying, you know, those who did not seek me, once again referring to the Gentiles, that they will find God and God would reveal himself to the Gentiles. So what Paul is pointing out here is this, that the gospel is being preached, it has gone out to the Gentiles, but this is something God already spoke of before time, that he would do this. And part of what he's accomplishing is that through the Gentiles is awakening the Jews to who Christ is. And verse 21, he says, but you know, third Jews of this nation of Israel, they've been, you know, this disobedient people, these people have been hard, who have not been willing to see or listen to the message of Christ. So what is he, so what's he setting us up for? In chapter 11, he's going to show how God is reaching the Gentiles. But through that, he is also trying to awaken the Jews and then eventually he's going to bring everybody together as one nation or one people in Christ. So that's chapter 11. But he set the stage here. The gospel is for everybody. The gospel is reaching everybody. Israel is aware of the gospel. It's not that they didn't, it went out from them. But the Gentiles are actually receiving the gospel. God is manifesting himself to the Gentiles. They're receiving them, receiving the gospel. But Israel is still being hard and stubborn towards Christ. So that's the current or the present state. The Gentiles are receiving Israel is hard and stubborn towards the message of Christ. What next? We go into chapter 11. Okay. I trust everyone is with me. So let's pick up in chapter 11 because it's actually a continuation of what he has been telling us. Let's read Romans chapter 11 verses 1 through 6, please. Romans 11, 1 through 6. How does he continue and get towards what he wants to tell us? Romans 11, 1 through 6. Anyone can read it. I ask then, did God reject his own people? Certainly not. I myself, I am in Israel, Israelite, at the center of Abraham, a member of the tribe of Benjamin. God has not rejected his people whom he chose from the beginning. You know what the scripture says in the passage where Elijah pleads with God against Israel.  I am the only one lived and they are trying to kill me. What answer did God give him? I have kept for myself seven thousand men whom have not worshiped the false God, Baal. It is the same way now. There is a small number left of those whom God has chosen because of his grace. His choice is based on his grace, not on what they have done, for if God's choice were based on what people do, then his grace would not be real grace. Romans 11, 1 through 6. Paul then asks the question, okay, you know, we are now in this situation where the Gentiles are receiving the gospel to Jews or Israel is still stubborn. So he starts off with another question, Romans 11, 1.  Has God, you know, cast them off? Then he says, certainly not. And he says, look, I am actually a Jew. I'm actually of the nation of Israel. I'm a Jew and I'm of the tribe of Benjamin. Look, I am a Jew. And yet God has not cast away his people. Then he quotes an oldest incident where Elijah tells God, God, I'm the only one who was not, you know, bowed my knee to Baal. And then God responds to Elijah and says, Elijah, actually, you know, I've got 7,000 people in the city. You're not the only one. I got a remnant. I got a people there who refused to bow to Baal. So he uses that incident there to say, look, in a similar way, even today, that even though it seems like there's a widespread rejection of the gospel among the Jews, yet among them, God has a people who said yes. And Paul says, you know, look, I'm one of them. I'm one of them who said yes to the gospel. And so he says, in verse five and six, there are people who have been chosen by grace. Now, again, that word election comes up to elect or to choose beforehand, to elect or select. Those who have been selected. But then remember, and then he emphasizes in verse six that this is by grace, not by works. That means these are people who have been saved. And these are people who have embraced the grace of God and not tried to get it there by their own works. But God has a people who've said yes to his grace. Okay. Now, that word election or selection, again, must be understood the same way. You know, we interpreted it in chapter nine, which is God's choosing or God's selection is not a partial selection of people eliminating or discriminating against others. Now, the invitation is given to everyone. Those who say yes, they become the chosen. So many are called or let's say all are called. Those who say yes to the call, they become the chosen should be understood that way. Because he's already told us whoever calls on the name of the Lord will be saved. He's already told us whoever believes on the Lord, whoever. That means this is for everybody. But those who say yes to the message of Christ, the gospel of Christ, they become the elect selected chosen ones because they say yes to the grace of God. We should understand it in that manner. So what Paul is telling us in verse Romans 11 1 to 6 is look, it doesn't mean God has given up on Israel just because on a large scale, there is a rejection of the gospel. No, God has not given up on them because even among them, there are those who have said yes to the grace of God. And Paul says, I am one of them. He's pointing to himself. Look like me. There are others that they have said yes to the grace of God. So let's pick up verses 7 through 10. Romans 11 7 through 10, please somebody could read it. So verse 7 through 10, what Paul is saying is this. So Israel as a nation, they missed it. They haven't got what they were seeking. What are they seeking? They are seeking righteousness, but they're seeking righteousness to establish it through the law. So Israel has not obtained what it seeks. That means as a nation, as a people, they have not been able to get righteousness. But the elect, that means these chosen people, these people who have said yes to the gospel, they received it, the righteousness which is by faith. And what about the rest? He says the rest are blinded. And so then he quotes two passages from the Old Testament talking the fact that in verse 8, God has given them a spirit of stupa. That means it's like slumber. They're just not awake to what is happening. They are blinded. And then he also quotes David from Psalm that their eyes are darkened. So he says, the elect have received, but the rest of the people are blinded. Now, what we must understand is that it is not that God has blinded them. It's not like God is causing them to, or preventing them from understanding or receiving the gospel. But where does this blindness come from? Or what causes this blindness? We can think of two sources. One, of course, is our own choosing to depart from the truth. That means for various reasons, we choose not to see the light. John wrote, he says, men loved darkness rather than the light. So one is our own predisposition. We choose to go away from the truth as people. And that's when God gives us up. He says, okay, look, that's the way you're going. You go. He gives us up to our own choosing, our own ways. So that's one source of blindness, which we chose to go away from the truth. The second source of blindness we know is from the devil. He blinds the minds of those who believe. He puts that curtain of blindness on people. So when Paul is saying, you know, God has given them a spirit of stupa. Romans 11 verse 8. Would God be self-contradictory? Would he, on the one hand, say, I want you to receive my son and the message of Christ, and then would he then work against himself and prevent people from receiving the message of Christ? Would he do that? Would he, you know, work against himself? Would he be self-contradictory? Definitely not. So when Romans 11 verse 8, when it says, God has given them a spirit of stupa, eyes they should not see and ears they should not hear to this very day. It should be understood in the same way that we spoke of Pharaoh when we said God hardened his heart. Romans 9. So did God harden his heart or did God allow him to harden his own heart? Because if God hardened his heart, then God would be unjust and unfair to punish him and his people. If God made Judas' sin. So, you know, we can ask a related question. Who sinned? Did God make Judas' sin or did Judas make the choice to sin and betray Christ? Because if God made Judas' sin and betray Christ, then Judas would say, I am the greatest savior because if I hadn't done that, Christ would not have died for people and people would not be saved. So Judas is the greatest savior and Judas would have the best place in heaven. Did God make Judas do it? Or did God speak ahead of time and say, there's a man who will do it, who will betray Jesus and did Judas make his choice to betray Christ? The answer is, of course, Judas made his choice. And when he realized this mistake, he went and hung himself. So it wasn't that God was making Judas to what he did. God allowed him to do it. God allowed Pharaoh to harden his own heart. And in that sense, you know, it says, okay, God hardened Pharaoh's heart or just let him go that way. So we have to understand Romans 11-8 in that same sense. When it says God has given them a spirit of stupa. So why would God prevent them from knowing Christ if he really wants them to know Christ? So we cannot say that God is working opposing himself, you know. So we have to understand Romans 11-8 correctly, that God gave them up. You know, like we see in Romans chapter one, we just quickly cross-referenced that. We see this in Romans one, verse 24, verse 26, and again in verse 28, Romans one, 24, 26, and 28. It says, God gave them up to uncleanness. Verse 26, God gave them to wild passions. Verse 28, God gave them over to a debased mind. Did God want it for them? No. But why did he give them up to them? Give them up to these things, because that was their choosing.  Is that what he wanted for them? No. So in that same sense, when it says here, God has given them a spirit of stupa, it has to be understood that they chose darkness, they chose to reject Christ, they chose their own way, and God said, fine. So in that sense, we understand, so from what Paul is saying in verse 7 through 10, Israel is not able to obtain what it wants, that is righteousness. But there are some among Israel who've received it by grace. The rest are in blindness, in darkness, and they are there because God has let them go that way. They chose to go that way. Then we pick up in verse 11, Romans 11, and let's read verse 11 to 14, Romans 11, 11 to 14, just another section. Somebody could read that for us. I say then, just humble that they should fall, certainly not. But to their fall, to provoke them to jealousy, salvation has come to the Gentiles. Now, if their fall is riches for the world and their failure, riches the Gentiles. How much more their fullness? For I speak to you Gentiles, in so much as I am an apostle to the Gentiles. I magnify my ministry. I may provoke to jealousy those who are my flesh and save some of them. But if their being is their weak concerning of the world. So Romans 11, 11 to, I think we just include verse 15 here, it's fine. So Romans 11, 11 to 15. So Paul is saying, so have they stumbled that they should fall? Meaning it's kind of asking a similar question. Verse one, he said, did God cast away Israel? He says, no, God hasn't cast them away because there are some people among them who have experienced grace. But then the rest are in blindness. So next question. So have they all just fallen? That means like, that's it. It's the end because they are in blindness and they are in a place where they cannot be brought back, have they fallen? He says, certainly not. He says, their sin. So, you know, it's very interesting here that word fall. Have they fallen or fallen? That means have they trespassed and they've gone out of the way. So they're being in blindness again. So that kind of corroborates how we explained the earlier verses. Have they fallen? Have they trespassed? He says, but through their fall or through their trespass. So it's very clear. It's their trespass, their fall. It's not God has put them in blindness, but their blindness is their trespass. It's their falling. Okay. So Romans 11, 11 says, look, they are trespassing. They have gone out of the way. They are in darkness. They are in blindness, but through their trespass, God, to provoke them to jealousy, salvation has come to the Gentiles. So what he's saying is this, look, they aren't sin or their trespass, they're in darkness, but what is God doing? Salvation has come to the Gentiles and God is going to use that to awaken them, to get them back, to provoke them. God is going to use that. And so he says, look, if they, verse 12, if they're falling away has been of so much benefit to the Gentiles, their failure has brought so much riches to the Gentiles, so much blessing. What do you think will happen if they get back in line? How much greater blessing. The implication is how much more the Gentiles will be blessed is what he's saying. And then he says, you know, this is what I really love to do. Although I am a apostle to the Gentiles, what I really love to do is somehow awaken, provoke to jealousy. Verse 14, awaken my own people through what I'm doing. So it says, you know, if any verse 14, if by any means I may provoke jealousy, those who are of my own flesh, that is the people of Israel, the Jews, and bring them and save them. So what Paul is saying is this, they are in darkness, they have chosen that, but the gospel has come to the Gentiles. The Gentiles are blessed, but what God is doing is that through that he's going to awaken these people. And he says, just imagine, if they're falling away, has blessed the Gentiles, how much more blessing will come once they are restored or brought to fame? That's in verse 15. He says, what if they're being cast away? Is it reconciling the world? What will their acceptance be but life from the dead? That means, you know, if they are going to come through the faith, it's this great grand resurrection that will take place. And in fact, that's what is going to take place. There's going to be this great revival of this. We're expecting it as Revelation even talks about it. There's going to be this great in-gathering of souls from among the people of Israel just before the final resurrection from the dead. So what Paul is telling us is this, God hasn't given up on Israel. He hasn't given up on them. They are in darkness. Some of them are being saved, but right now the gospel is gone to the Gentiles. The Gentiles are being blessed and if Israel gets saved, it'll be even a greater blessing to the Gentiles. And then he develops this further. Let's read from verse 16, Romans chapter 11 and verse 16 was, yeah, sorry, Romans 11, 16 to 25. Romans 11, 16 to 25. Somebody could read that please. For if the first fruit is holy, the lump is also holy. And if the root is holy, so are the branches. And if some of the branches were broken up and you, being a wild olive tree, were grafted in among them and with them became a partaker of the root and thickness of the olive tree, do not boast against the branches. But if you do boast, remember that you do not support the root, but the root supports you. You will say then, branches were broken up that I might be grafted in. Well said, because of unbelief they were broken up and you stand by it. Do not be haughty, but fear. For if God did not spare the natural branches, he may not spare you either. Therefore, consider the goodness and severity of God on those who felt severity, but towards you goodness.  And then also if they do not continue in unbelief will be grafted in for God is able to graft them in again. For if you were cut out of the olive tree, which is wild by nature and were grafted contrary to nature into a cultivated olive tree, how much more will these who are natural branches be grafted into their own olive tree? One more verse, verse 25. For I do not desire present that you should be ignorant of this mystery, least you should be wise in your own opinion that blindness in part has happened to Israel until the fullness of the gentiles has come in. Thank you. So, very interesting how Paul presents this truth to us. He is painting this beautiful picture of the olive tree. And what he's presenting to us is imagine two olive trees. One is this cultivated olive tree. So, an olive tree that's part of a cultivated area. It's being taken care of. And then there's a wild olive tree, something that's growing out in the wild. And what he's saying is, he's saying, you know, this cultivated olive tree represents what God himself is doing. Right? First came the and the roots and then came the olive tree and it was growing. So, they're presenting Israel. So, the olive tree, olive tree representing Israel. And then he says, but some of them didn't believe.  And then he took some branches from the wild olive tree that those who believe that is the gentiles and he grafted them in, put them in, made them part of what he's doing.  Because remember, the tree standing there because of the roots and the roots, the origins were the Jews. It started there with Abraham, right? It started there as with the Jews. So, don't boast as though we are superior or better than the Jews. No. They were an unbelief that is verse 20.  And we came in by faith. And so verse 20 says, you know, we stand by faith. And that's how we are in. But don't become proud. Instead, verse 22, he says, you know, but I want you to consider the goodness and severity of God. So, there is both God's goodness and God's severity. And there are two sides. God is God of truth, but he's also God of justice. He's a God of goodness, but he's God of severity. That means, you know, God is good to those who are responding in faith, but then to those who are unbelief, he has to deal with them in severity. But then he says, even among the Jews, he's able to bring them in if they will respond in faith. If they don't continue in unbelief, verse 23. That means, even the Jews, if they turn in faith, he will put them back in, craft them in. And so Paul says, you know, that's verse 24. He says, think about how, you know, how God is grafting the wild olive tree, the branches of the wild olive tree into the main olive tree.  So that means this is a secret that God is revealing now that the plan that's going on on the earth is this. God is bringing in branches of the wild olive tree into the cultivated olive tree. He's integrating them, bringing them, making them part of what he's doing, his original plan. But he's doing this, and notice verse 25, that blindness in part has happened to Israel until the fullness of the Gentiles has come in. That means God has permitted, has allowed Israel to be in the state of blindness until Gentiles are brought in and grafted in. And then God is going to wrap this up by awakening the Jews. So he says, this is a mystery. That means this is a secret that has been revealed. This is what God is doing on the earth right now. That is, it's the fullness is waiting for the fullness of the Gentiles.  So the picture here is he's grafting the branches of the wild olive tree into the cultivated olive tree. That's the plan that the great plan that God began. He's getting them into that plan. And then he's going to go after Israel. So that's the remaining part. Let's read verse 26 to 36, please, verses 26 to 36. Somebody could read that. And so all Israel will be saved. As it is written, the deliverer will come out of you and he will turn away ungodliness from Jacob. For this is my covenant with them. When I take away their sins concerning the gospel, they are enemies for your sake, but concerning the election, they are beloved for the sake of the fathers for the gift and the calling of the God are evocable. For as you were once disobedient to God, yet have not obtained mercy through their disobedience. Even so, these also have now been disobedient that through the mercy shown you, they also may obtain mercy. For God has committed them all to disobedience that he might have mercy on all. Oh, the depth of the riches, both of the wisdom and knowledge of God. How unreachable are his judgments and his ways past finding out for who has known the mind of the Lord or who has become his concealer or who has first given to him and it shall be repaid to him for of him and through him and to him are all things to be glory forever. Amen. So Paul brings this section to a conclusion by saying verse 26 and so all Israel will be saved. As it is written, the deliverer will come. So he's quoting from the Old Testament again, that's verse 26. The deliverer will come from Zion and God has said, I will take away their sins. So of course when he says all Israel, it doesn't mean every individual what he's saying is salvation will impact or touch the people powerfully once again. Those who believe will be saved. So this is the mystery. How has God working with the Jews and the Gentiles? The gospel came to the Jews. From the Jews it went out to the Gentiles. Right now the Jews are still stubborn and not opening up to the gospel of Christ or the message of Christ. The gospel is going to the Gentiles and people all over the world are receiving the gospel. But God is waiting for the fullness of the Gentiles. That means to see, you know, the many of the Gentiles respond is grafting them in. He's bringing them in and making the Gentiles part of what he has started out with the Jews. And then ultimately it's going to be back here. He's going to use this to touch the nation of Israel or impact the Jews. And he said all Israel will be saved. People, the Jewish people, will wake up and receive the gospel. So he says right now verse 28, right now, as far as the gospel is concerned, they may be your enemies. But concerning God's choosing, they are beloved.  They are the root through which God's plan is still work at work. So as far as God's purposes, God's election, God's calling, God's choosing, look, they are the root and they are the main cultivated tree through which God has been working out his plans and purposes. Then verse 29 is that classic verse. It says, the gifts and calling of God are irrevocable. So God doesn't change his mind on his calling, his choosing, his gifting, his purpose. He doesn't change his mind. So when God has called somebody, you know, he's there for it. He doesn't change his mind.   He's not going to abandon you. But some, he's going to work out his purpose in your life and mine. He's going to do that. So that's the wonderful assurance we get there from Romans 11 and verse 39. And so he sums up by saying, you know, think about this, that they are disobedient, but through the mercy God is showing to the Gentiles, they are going to come and experience the mercy of God. So even though God has, you know, let them go, committed them to disobedience for now, the mercy is showing to the Gentiles. It's actually going to get them, get the Jewish people back to what he's doing. And so basically, verses 33 to 36 is like a, is Paul just celebrating this mystery that's been revealed, oh, the wisdom of God, or how wonderful God is in his working, that this is God at work and his ways are unsearchable. His ways are beyond our understanding that what God is doing in the nations is actually all coming together to his plans, his purpose. It's the unfolding of his plans, purpose is all actually coming together for everybody, the Gentiles and the Jews to experience the mercy of God. And so Paul says, you know, how wonderful are his ways, his judgments and his ways are there beyond our understanding. And then he quotes from the Old Testament again, who has known the mind of the Lord, who can instruct him, who can teach him all this.  So to sum up, you know, God has not given up on the Jews or the Gentiles. He is still at work. And among the Jews, there are still some people who are responding to the grace of God. He calls them the remnant. Right now, it's the time for the fullness of the Gentiles. God is gathering the Gentiles, the wild, all the tree, grafting them and bringing them in. But the mercy that he's extending to the Gentiles, he's going to cause it to awaken the Jews so that they too can come and experience Jesus Christ. And when that happens, he says, how great a resurrection, I mean, what a great day it'll be, because it's going to result in the resurrection from the dead, indicating that, look, it's coming to, it's all building up to this great grand resurrection time, resurrection day. Right. So that's Romans 9, 10 and 11. What is God doing with the church and with the Jews? I hope it's clear. Any questions, any thoughts before we close off today? Or you can think about it as well. We can ask questions next week. I know it's just three more minutes, but any questions, any thoughts? It's all clear, I think. Okay. All right. I see your comments in the chat. Sounds good. So we will pick up from Romans 12 next week. And interestingly from Romans 12, he gets back to addressing the church. So Romans 9, 11, 12 was trying to explain to the church what God is doing with Israel. Then Romans 12 onwards is back to speaking to believers about Christian life and living and what they have to do. Okay. So let's just wrap up and close in prayer. Could one of us please pray and then we will dismiss. Father, we thank you for this time, Lord. We thank you, Lord, that you continue to teach us through your word. I pray even as we continue to learn that you will abhor your wisdom and your knowledge, Father, open up our eyes to the hidden things of your word, Father. I pray and Holy Spirit help us for these words to bear fruit in our lives, Lord. In Jesus' name I pray. Amen. Amen. Amen. Thank you. All right. Thank you, everyone. I enjoy the rest of the day. I'll see you all in the next class. Thank you. Bye now. Thank you so much. Thank you. Thank you, everyone. Thank you.