Today in this fork we are going to focus on a way we can guarantee retrieval from for users that are storing their data in a decentralized storage network and in particular while we're thinking about how we want to solve this problem we want to solve this problem for any kind of data so we want to be a web scale we want to assume that we are dealing with the entire data from the web and this in particular means that we don't want to have any constriction of the onboarding throughput of the data for these kind of solutions. This is the agenda for my talk and basically the first topic I want to talk very briefly is Kryptonet. Kryptonet is the lab I'm a researcher in a protocol lab and we are an open distributed research lab this means that we are a small set of researchers that try to not just we worked on research and primitives especially photographic primitives that are the building blocks for web 3n and distributed storage but in particular we also try to bring this work to the entire community and influence the entire research community to what we in the direction we think are important for for web 3 and this some of the results from this lab are papers like here you see some of the published papers there are more on submission from DZRs another line of work brings improvement for the five coin protocol many fibs the last one for example snap dealers knockback you may heard of them if you are following five coin protocol but more in general we have like a lot of ideas we open in we work in the open so all the ideas that we even are just brainstormed you can find them in our website in our notebook and the nice thing is that some of these ideas they manage to become a first protocol protocol design work and then real product one of these is the project that I'm going to present today the data retrievability consortium before speaking about data retrievability I want to spend a bit of time on related problem and concept like data retrievability in order to build up the the the definition of data retrievability and understand it better so if you are like following recent scanning solution for xarium or in general for blockchain you may hear about the data variability data variability is a protocol that has two steps this dispersed and retrieval steps and it's about first you disperse the data in the storage in the in the storage network and this means that the the the owner of the data the client will do some processing of the data and process the data and then basically you can think split the data in many blocks and and send this to the network of the storage providers this is going to be some kind of depends on the protocol some kind of agreement on the fact that this dispersal was was done in the correct way so that enough notes received enough blocks and if this is is this step is successful then we can have later on when is needed the retrieval step that is giving back the data so oops sorry what what we have here is basically a protocol that gives you also retrieval but only when the dispersed is successful and also has to assume for the retrieval tool to happen in a successful way that a fraction and how much depends really on the the specific protocol that they know that receive the data in the first step are are honest and willing to serve the data so this this protocols there are many protocols that are very efficient that works very well but they work well with some specific data like for example as I said they are good for for roll-up solution because they work well for small data like status the roll-up the data you need for roll-ups because you mean the you still have to go to these these dispersed steps first of all that requires a consensus or some kind of like consensus so this limits your throughput of data so you can think about using this for web scale data and of course as I said the retrievability is not fully covered in the sense that that it works only if there is an honest provider or not in a provider network that is going to to serve the data something related to to data variability is the more general proof of storage proof of storage for example is the building block of five coin and here you can think you still have two steps so you have the source step where actually now it's it's like the client going to many different providers or not in the network and with each one of them is going to create a storage deal to store the data then these miners they're going to use these data the fact that they have the data to create this proof of storage okay each one of them that can take their own proof of storage and the proof of storage then is used to it is registered is appears on a blockchain for example five coin and is used to mine to mine the the native coin there the native token there and and this gives incentive to these providers to actually keep storing this data so there is a strong incentive mechanism here that assure this step is done in the correct way and the retrievability is again just live as an assumption that there are if you client to store your data with enough providers and there is going to be some of them that are available to sell back the data when you need so the nice thing of this solution that the incentive economics first of all and second gives you unbounded throughput so this this client in there can now really upload any data very fast is not is not bounded by any consensus algorithm on the data itself and and but as I said the retrievability is again somehow let me say under specified so it's just say okay we there are going to be one provider willing to serve the data this our assumption okay so now that we have seen these two problem I think it's clear that there is some maybe missing point here or like something that we miss that is how we can go to the retrieve step and make it stronger not just assuming that there is some honest note that is going to serve but that we can have a strong incentive exactly how like we have for the second one store so that is exactly this we think that we can create we want to create an incentive system for the the provider to serve back the data to retrieve the data how we can do that well if we can have something like similar to the proof of storage let's call it proof of delivery then we can basically do almost the same same same scenarios the real problem is that there is not a proof of delivery this is like almost we can call it that there is there are impossibility results in this research area that says that if you have just a client provider and they start to complain that the client asked the data but the the provider didn't give it back you don't know which one of the two is lying unless there is some other assumption and we need the the assumption that we need someone that is the witness of this delivery so let's let's see a bit better what kind of assumption we we we can have and and by the way I didn't say it at the beginning sorry but like I'm if there are questions in the middle feel free to stop me sending the chat or some way and I'd like you to to to stop an answer in the middle if it's more useful uh so let's see some of this uh some of the assumptions that we can have to this scenario's client provider to make it uh data retrievability possible one first idea that we can have is use the blockchain itself uh as a witness that is meaning forces that are provided to store everything on chain the chain sees the data and the data are then we can retrieve the data from the chain this is unfortunately too expensive for large data this can work for very specific small uh type of data um another idea is using a proof of retrievability proof of retrievability is something that is known in the literature and and it's like an interactive protocol it's a proof system basically between the approver and a verifier there is a protocol that they need to to to follow uh there are actually many different flavor of this of these primitives and and the property of these primitives says that at some point if prover and verifier like client or provider follow this protocol basically after some repetition of the protocols the answer that the the provider is giving to the client that is checking the storage of the supervisor will leak the entire data the problem of this solution is that again as the same as before we need too many it's not it's not efficient because we need the really many interactions so it's going to be a retrievability that is very slow and through time it's not one shot say retrievability um so what we we we tried to to to come up was like some easy way to have a witness an oracle of the retrieval exchange why uh why that having this oracle that is that is a witness of the of the exchange works because say that you have your client doing the the the deals with many providers but then no one of them is actually answering the retrieval query from this provider if we have an oracle the client can appeal can ask to the oracle to basically repeat this retrieval request to the all the providers or one in particular okay and this oracle is kind of trusted to answer what he really is going to see the answer that is really going to see from the provider um and if the provider is in this case not going to answer since we trust him we know that the client is the honest one and is is claim about i'm not getting my data back is is a is a call that is a truthful one and we can do some action for example we can punish we can do some apply some penalties with the provider if the provider is going instead to give back the data to the oracle we are at the same way because this at this point you can just assume that the oracle is going to send back to the client the data so in this way we basically construct the way or where the data are given back to the to the client or the provider going to be slashed so we can some guarantees like we can say hey provider are going to to send back the data to do the retrieval serving the correct way because they don't want to be slashed so the question now is how do we implement this nice guide oracle we don't want to have a clearly a centralized party to do this so what we did we create basically a solution that has a small trusted set of practice that we call the referees this is what we called it this our solution is the data retrievability consortium and is based on having this referive committee so you can think of this about the network of special notes called the referees it can be doesn't have to be very large size can be small like 20 25 notes is enough we don't have to trust all of them we need to trust a fraction of them for example in our prototype we assume we trust half of them and now the protocol goes like this and basically client provider they will agree of chain they can do a retrievability deal means deal means that they agree on the duration of so for how long they contact is is valid some payment for this service from the client to the provider and some collateral so the provider is going to lock down some collateral that will guarantee the retrieval okay and it's actually the one that we are going to take from the provider if it doesn't do that uh so if the client is satisfied with the retrieval service nothing happens if the client doesn't get requested for service for for a deal for a data that he has a deal on it can appeal to this small nectar of referees and this nectar will basically just they will do what I just explained before with the article they try to retrieve the file with the provider if they succeed okay fine the forward the file to the client if they don't they're able to take the collateral that was locked down and basically uh born in or like just just remove it from the balance of the provider so this is the high level what is really important how at least we spend a lot of time to optimize how the real the trial so the what happens after the appeal from the referee by the referees how this is done because first of all we want to guarantee that you know even if some of the referees are somehow are malicious and they collude maybe with the malicious clients would provide them as no slush and we want to guarantee that if some referees are not online provided that the doesn't get slushed the good ones so we have to think and also we want to be efficient we don't want to like just go all 20 referees go and ask the file and the provider to answer to all of them this kind of situation we we want to we wanted to avoid those so after some some research we we can come up with the protocol that has actually actually rounds in each round only one of the referees to ask the file back so the provider has to answer only one referee and then the referees is responsible to convince the others that the correct file was was obtained and we actually need like several referees to say okay this provider is really bad and then only after some of them like say again a fraction one third of them that really agreed then we really slush the the provider so we have all these like a security measurement in place and what I want to say is that we have a in April we managed to have a small prototype of this that is implemented basically by a smart contract that is live on an Ethereum test neck and thanks to the smart contract there is the smart contract then three only for this prototype referees that are simulated by by by by us basically you know in some of our by our code in some of our machines and the smart contract is can be used to create the deal that is going to be posted on chain and can manage the deals that can do this lashing so we drove the funds from the funds from the provider you can play with the prototype with this client demo that we have a plgl.dev and if you if you go to this website and you connect your metamask wallet you can play I see create a deal and manage your deals after that after the test of the prototype now we are working for shipping a real test product so and the plan is to ship something at the end of October so end of this year we have some intermediate milestones the the first one is to actually have the product ready I'll say a bit more about it now what we mean by going from prototype to product and the second one intermediate milestone is actually to find and board partners and find the right product marketplace so if you think you can be a partner or this like provider or especially you want to be a referee please contact us as soon as possible because we are super interested in this kind of collaboration and going from prototype to product means that we want to make this more usable and and more more flexible for example we are working on adding NFT collections for showing the deals so if you are a provider you are doing deals you are all these deals will appear in a specific NFT collection so it's going to be very easy for you to show that you have many deals active and to manage your deals you can even create a market of these deals later on we are working on adding an admin function to the contract to change the parameters that we are putting there we are working on a reputation score based on how good you are in doing this refurbished deals as a provider and we are working on for example working having an idea not just for one specific file but for a collection let's say a folder of file all these are features that we think are important to really make this something that we can use in in the other storage scenario and we also have some planning about documentation and a website and that's that's it thank you a lot for information for your attention any any question I'm very happy to answer I want to thank all the team and this is not my project is a fit to net project and I work on this with Luca and Nicola but I also want to thank Alex and Nicola for the feedback and the implementation is done by Yomi Digital and we have Jonathan from the helping for PM and also thank you a lot for the crypto economic team for all the review the crypto income review part and especially to Danilo


St. Lucia continues to strengthen ties with the government and people of Taiwan on a cultural level. A number of St. Lucians are again participating in the annual Lantern Competition, in commemoration of Taiwan's National Day, celebrated on the 10th of October. More in this report. The Cultural Development Foundation, in collaboration with the Embassy of the Republic of China, Taiwan, was the second annual Best of the Best Lantern Competition, in commemoration of Taiwan's National Day celebrations. The competition is being held under the theme Taiwan, St. Lucia Strong. In the preliminary round of the competition, 17 entries lit the halls of the National Cultural Center in hopes of advancing to the top 10. The participants spared no effort in presenting portrayals of cultural significance to the two countries and Taiwan's diplomatic ties to St. Lucia and agriculture, education and technology. Dr. Mona Henry-Win is the Executive Director of the Cultural Development Foundation, CDF. Participants are normally given a stipend to create because, as you well understand, a lot of them are unemployed at the moment because there aren't that many activities happening and that is the incentive that we offer them to be able to create those lanterns. And the lanterns, irrespective of the themes, what they highlight is the cooperation between St. Lucia and the Republic of Taiwan, all of the gifts that they have given to us. So it's the CDF's way of saying thank you through the artists and the creativity to the people of the Republic of Taiwan. The competition serves as a form of creative reprieve to the participants from the effects of the COVID-19 pandemic. The participants in this year's competition conveyed their gratitude to the organizers for the opportunity to contribute to the event. It's been a tough time for artists in St. Lucia and for the arts on a whole. So participating in this lantern competition is not something that I normally would do. This is my first time. But I needed for St. Lucia to realize that we are alive and well and I was excited to just do something creative, do something different and also show the appreciation that the people of St. Lucia have for Taiwan because Taiwan has learned a lot for this country. Participating in the lantern competition for me was a wonderful experience as a costume builder who never took part in a lantern competition ever. So this is my first ever lantern. Of course COVID tends to bring out the best in us. Of course as we all artists try to defy all the challenges for COVID and of course we had some time because you know things are not too bright on our side. So it was an opportunity for me to express my creativity and supporting the arts and cultures as much as I can. The only thing for different, so I did a big fish to represent Taiwan and the total to represent St. Lucia. And I hope that the best turn makes it today and then it goes down to the last three or four. One lantern will be chosen as an exhibit for the 2022 Lantern Festival in Taiwan. His Excellency Peter Chen, Ambassador of Taiwan to St. Lucia, expressed his elation with this year's entries and the growth of the competition. I'm really amazed by the magnificent lantern this year. Although last year already fascinated but I think this year all the artists spend more time and bring out more thoughts or a better idea to make this lantern. And I'm glad that I'm not a judge because that will give me a hard time. The winners of the lantern competition will be awarded $1,500, $1,000, $700 to the first, second and third place, respectively. $500 will also be awarded to the participant of the most innovative Lantern. From the Government Information Service, Humadi Mack reporting.


Hey, what's up, YouTube? It's Zeke and welcome to The Dream Green Show. Today, I'm going to show you the easiest indicator to starting your way to becoming a day trader. So let's get into it. All right, YouTube, we're back. Today, I'm going to show you how did I get into day trading about two years ago and I had a quite bit of success with it by using just this one indicator alone. A lot of people think that day trading is super difficult and that you have to wake up at 4 a.m. every single day just to become a day trader. And it's some way it is difficult, but once you get the system of everything and you have all of your indicators set up, all you have to do is just stick to your basic rules and make sure that you win more than you lose. But if you're not interested in today trading, what you can do is swing trade. I will show you guys what indicator I use to set up my swing trades. And if you don't know what swing trades are, swing trading is pretty much buying low and selling high. Day trading is buying the same day and selling the same day and you become a pattern day trader. But swing trading, you could hold a stock for anywhere from I think short term would be a week or a month in long term would be six months to a year as a swing trader. So let me show you the indicator that I use that I find for my day trades and for my swing trades. All right, it is called the RSI, the relative strength indicator, or the relative strength index. Here's the definition of what it is. The relative strength index is a momentum indicator that measures the magnitude of recent price changes to evaluate overbought or oversold conditions in the price of a stock or other assets. The RSI is displayed as an oscillator, a line graph that moves between two streams and can have a reading from zero to 100. It is intended to chart the current in historical strengths or weakness of a stock or market based on the closing price of a recent trading period. All right, so it sounds like a lot of words that I just read out, but I'm gonna actually pull up a thicker swim as the platform that I use to actually read all of the stock markets that I set up my indicators on. And once I show you exactly what it is, you guys will find it very simple yourself. This is probably the very simplest indicator that you guys can use if you want to start day trading or swing trading. So let's pull up think a swim right quick. All right guys, here we are on think a swim. I'm gonna pull up my favorite stock. If you've been following me on my channel, you would already know that my favorite stock is AMD. If you don't follow me, go ahead, hit the subscribe button, the thumbs up button. And what I just found out is that if you hit the subscribe button that it really doesn't mean anything at all. So you also have to click the notification button next to the subscribe button so you guys can get update to my current videos. And I'm gonna be doing a giveaway very soon so you don't wanna miss out on that opportunity. But anyways, back into AMD. Okay, down here I have what I have set up. It's the RSI indicator. All right, so let me explain it to you right quick exactly what it is. This is the price movement of AMD. This is the four hour 180 day chart. So this is the actual price movement. This charts the price. Now here's RSI. If it's overbought, it would show that it's red at the very top. That means it's overvalued. People are buying AMD based off speculation and that is on the momentum wave of going up and people are buying it at a super high price. And I have it set up that it would turn red if it's above the 70. It goes all the way from zero to 100. I have mines set up to where if it's over 70 it's gonna show red but you can change it to where if it's over 80 all the way up to 100. So when it's very high and it's red that means it's overbought and the price is probably gonna pull back a bit. If we look right here where it's blue that means it's actually oversold it's undervalued. People are selling off their shares afraid that the price will go down anymore and that the company is actually under value right now. So right down here where it's blue where it's underneath the 30 I mean is undervalued for the company and you might be getting in I said you might be getting in for a good price if you could get it whereas undervalued are oversold. So this is overbought when it's red and it's oversold when it's blue. Okay. So we take a quick look into let's zoom in right quick to right here. So last time that it was overbought was over the 70 right here and it had a little pull back right there. All right.  Once again when it was overbought right here it went all the way up to the 84 the 83.7 so it was super overbought it was overvalued and over the next couple of days and tanked and went down 12%. So you could have sold while it was at the very top and waited for the company come back down and bought back in once it reached back down to a fair value around the 30. Now we zoom out let's go to one that was oversold let's zoom in right here. So the company down here was super duper oversold and it went all the way down to the 1817. So remember that the chart goes from 0 to 100 and this one was all the way down to 17. If you could have got in at this fair under value at $26.77 and you could have rolled the wave all the way back up to the next time it was over overbought right here and sold it at for a percent gain of 27.33%. So in a couple of days you could have made a profit of 27% in just a couple of days but you also always have to keep an eye on the market when you're swing trading and day trading. So let's zoom out just a little bit more so there you go. It was overbought again right there on the RSI indicator and it ended up coming right back down. So let's look for one more chance to where it was oversold and it hasn't been oversold since right there. It is super overbought. It is all the way up to the 84 and it's showing a little pullback right here going down let's see going down six point. No, going down five points right there. No, 4.8%. All right. All right guys. So that's how I use my RSI indicator on my swing trade setting it up just like that. When it's over about I'll sell some of the shares off wait for the price to come back down and buy some more and when it's oversold I'll buy some when it's oversold wait for the price to go up and sell it at the top. That is the very basic way of day trading very basic way of swing trading. As you can see I also have other indicators set up on my chart that I'm going to discuss in future videos. So you guys subscribe to the channel so that you can see exactly how I set up my chart. But if you guys want to use the RSI indicator that is the most basic and simple way to value a company. Now if you want to be a day trader what I used to trade when I was day trading was oil and gas so I would pull up D gas right quick and when I pull up D gas D gas let's go to the one day one minute chart. That mean you are trading intraday you're trading you're buying and selling the same exact day and if we're using the RSI indicator way down here where it was super oversold it would go all the way down to the 13 you would have bought it right there and sold somewhere near the top and you would have had a profit of 3% in a single day. And the last time it was oversold was right here and went all the way down to the 18 we would have bought and sold for a 1% profit. If you guys don't want to be greedy you can just if you make 1% a day you are the best trader on earth. If you make 1% a day that mean you would grow your portfolio 365% in a single year that is awesome. If you wanted this game a half percent a day that's awesome or just even 0.25% a day that is still great being a day trader because you would grow your account very fast over time if you have more wins than you do have losses but me personally I am a swing trader because I am a busy a very busy person and that's how I do my swing trades with AMD actually that's how I did my swing trade with Google I bought Google at a very cheap price when it was oversold and it was undervalued and now on Google I have made over $100 from Google stock already and I had it for less than 2 months. So yeah guys, so yeah that's how I do my swing trades but other than that if you guys want to find out how I use all of my other indicators go ahead hit that thumbs up button and subscribe and actually click that bell icon that's next to the subscribe button because trust and believe that I'm going to be doing a giveaway very very soon and you guys don't want to miss out on that giveaway but other than that this is Zeke bringing you the dream green show and I'm out. Peace.


Some additional ideas for the future simple tense include things like horoscopes. Here, you'll divide your class up into groups, provide them with a zodiac sign.  They'll share their horoscopes and see who that actually applies to. Then, we have our fortune-telling. You could use this as a role-play, whereas one student or a pair of students comes to see a fortune-teller. Now, the fortune-teller will make statements such as, you'll have a baby next year. You'll get a great job promotion soon, so on and so forth. Finally, we have our wedding vows. You could encourage students to create their ideal wedding vows for their partner, or some silly wedding vows, anything that will basically make a promise. This could also include employment contracts, so on and so forth.


What's your name? How can I help you? I'm Ash. Hi. You've conducted a smidgen of trolling. So, we may have done something. Yeah. I'm not associated with this. Here it is. What did you do with this? So, we have managed to make the Dashie Cam Cumin. Yep. You used my Balsamera to make Cam Cumin? Yes. No, that should not even be possible. Cam was only 1% of an anomaly. We got rid of it. Yes. How? Who? What? Why? Well, Doctor One payment isn't doing too good right now. Doctor One payment isn't doing too good? Yeah, he brought him and made him human. Oh my God. Wait, how do you know that it works? Doctor One, how did we come to this conclusion? Well, how things have shown is it seems that Cam became a lot more avid and a lot more like, they talked about this voice in their hair before, and the voices have told them to bring people out of the idea, get them out, but the voice is gone. They said that it stopped. And you mentioned earlier that Cam had been acting like a person?  I need to conduct some sort of test to make sure that this isn't actually, like this is real. If I can draft up a test, can I trust G3 to execute it? Yeah, sure, sure. Okay, can I, give me like 30 seconds, I will create a test, and then I'll hand it over to you guys to execute. Wonderful. Thank you very much. How are you doing sweetheart? Not good. Not good? This candy isn't working. It's not. It was my voice in this week. I don't know, there's something up with my powers. I gotta keep looking into it. Because I honestly don't know what's going on, and I need to be kept in the loop as security, you know? So if we could just kind of like share things that we've found, maybe if we could like try and focus on one person to interrogate, or literally anything would be very helpful to me. Well, I have not seen any sharks here to punch yet. I came here for the sharks, so... I saw a shark, however, if that were to happen, I think someone would be particularly angry.   Yeah! We want you hiding a bodgy. Okay, we have a couple testimonies here. Is he, is he not killed the bear? We killed the bear? It was an accident. Yes! You hid the body! You still hid the body! Let's gather some semblance here, people. Self-animal deaths aside, we need to be focusing on the actual murder of Carter here. Like the body! That's what I want to figure out. Does anyone have anything they want to share that just maybe someone's a little suspicious? Like, Brent said, I think it'd be a good idea to like maybe interrogate someone. I feel like we're just running in circles right now, talking over each other. He's the one with the shark plushie, I don't trust him. We'll keep that in mind! Hold on, Jenna. Let's take turns speaking, because if we speak over each other, it's not going to get us anywhere. Okay, go ahead. Okay, so I don't know if anybody else has kind of been thinking about this, but I'm kind of just noticing things in timelines, correct me if I'm wrong, if anybody else has any information, please let me know. I'm not saying Sloan should be suspicious, but Sloan was a little bit quick to scan Ren here with that being the last scan that we needed to figure out who this person who was the murderer is, possibly. Now, it was wasted on the jar, so that means that we can't rely on that one scanner if we were correct to indicate who the person could actually be. So we have to rely on mentalities, we have to rely on timelines and stuff like that too, okay? Something that's one, first of all, instantly suspicious. Second, I was talking to Ren a little bit before her incident happened with the scanner. She did notice a little bit something around 2 o'clock-ish about... Yeah, Ren, could you remind us what you saw? I saw Sloan walk into the bathroom and talk to Ken. And what time was the murder? What time was the murder?  Like at 3? Yeah! Yeah. It was like right after the murder. Sloan, you wanted to go talk to the murderer after the murder? Why are you explaining yourself? No, I didn't. I was in bed. Exactly where I should have been last night. In bed? I was not out of bed.  Why was that? She's a security. Yeah, she's a security. She's going to add that... She's got the arm band. From others, I've heard that... I've heard you'd say that he was out of bed. So you had to be out of bed to say that he was. We share a room. That is true. We live in the research quarters together. So can you confirm the alibi? No. No! You can't confirm the alibi. He was asleep at that time. I cannot confirm that. Is that just because you were asleep and... Yeah, I'm like... Trust me. I was trying to get to sleep after what happened.  You weren't in bed. No. What do you mean you weren't in bed? What do you mean you weren't in bed? What do you mean you weren't in bed? I will say I don't know what this means, but if it's helpful to the group... Absolutely. Then might as well share it. I was told very early on in the night... I've been talking to Cam. And Sloan told me to deliver a pen of some sorts to him. And just said it was a symbol of hope. It is. So... I don't know again if this means anything. Actually, I have a question. So the foundation is well known to use amnestic protocols to wipe memories and everything. Yes. Who here within, basically, this area, who is in, basically, a possession of amnestics during this time? I mean, this would be... Edgar? Rim, actually. Security, right? Security personnel are the only ones authorized to use and carry amnestics. Yes, that's correct. And upon asking Edgar from earlier, I would say that during his warning counts, all of the amnestics were still there. So when you guys saw Edgar carry Cam into the bathroom, was it... We protect the sweater with the cubs. I mean, there was a lot going on. I didn't... You're protecting Cam in wondertainment. I would all remember this. Yeah. Yeah, the two of them had carried the body into the bathroom just by themselves while the rest of us were essentially moving cars while they were cleaning up the blood. Wait, what? They just came out into the bathroom? They're so blunt on the floor. They were there about a few minutes ago. That's fair enough. It was angered you. Yeah, and we're at... The security person, you remember using this extremely carry. No. I don't worry about amnestics on you. Should we say some of the interrogations? Did you tell me that you moved the body yourself? Edgar? Did you move it all the way? You say you kind of get mixed up. You know... Mixed up? Mixed up? Mixed up. I did. I... Was Ren there? Ren was there. Yes. What? Ren, were you there? Who's body? When we moved Cam into the shower. Oh, what a man. She was there. Right? I mean, we were all there. Why leave her out? So who are we going to be investigating? There's a lot of fingers moving in a lot of directions. Sounds like we need a vote. We need a vote. We need a vote. We need a vote. We need a vote. We need to see who we should interrogate. Yeah. Just vote for... We think it's the most suspicious. One last thing to say. Sloane, can you openly tell me, how was your and Cam's relationship? I just wish to know for... This sounds like an investigation. Not a vote. I mean, if we... Hey, hey, hey! Sloane, we can ask all those questions. That's true. This is for an interrogation. Exactly. I mean, if you really want me to vote for you so that I can get the answers that I need for it, so be it.  And that is that Cam appears to have had amnestics used on him. And I have been trying to find a way to reverse that effect so that we can get Cam's account of the situation. And Sloane has been the only person helping me to reverse those effects.  Yes, Sloane was guilty. Why would she want Cam to remember and therefore inform us of her guilt? That's fact. That's fact. Okay, that's good. Let's go ahead and vote. Let's take the vote. Let's take the vote. Let's do it. Only vote once. Only vote once, it is. Sit down. We should investigate Iris. Okay. That'd be crazy. I'm sending one thing. We should investigate Izzy. Yeah! One vote for Sharko. Yeah! Great, yeah. Oh, Rimsley. I'm walking gospel. Yeah, go on. My protocol is security to sabotage this foundation site in any way. Hashtag not daddy, entertainment. It should have been... Oh, my God. It should have been regular MS6. Someone's tampered with the supply. But why would he tamper his own MS6? I mean, he was running it, right? Someone's trying... But he wouldn't use it. If he really was poison. Yeah. Everyone makes some room. We've got to move the body. Oh, my God! I think this is kind of a little crazy. Things have gotten a little crazy. We've got one for... Da-da, da-da. Thank you for listening.  Please become a patron or visit our merch store at the link in our bio to support our work. Secure. Contain. Protect.


Live from Vancouver, Canada, it's theCUBE at OpenStack Summit Vancouver 2015. Brought to you by headline sponsors EMC and jointly by Red Hat and Cisco with additional sponsorship by Brocade and HP. And now your host, John Furrier. Okay, welcome back everyone. We are live in British Columbia here in Vancouver for OpenStack Summit. This is theCUBE, our flagship program. We go out to the events where we're going to extract the signal from the noise. I'm John Furrier, the founder of Silicon Angle. Join the next guest here, Jerome Lacave, the CEO of Scalely. If you've been following what we've been doing with CrowdChat in theCUBE, you know Scalely. They did a great big deal with HP and we've had a lot of conversations on the web that many of you join the conversation or can go there on CrowdChat about Scalely, their relationship with HP and also what's going on in OpenStack. Jerome, welcome to theCUBE. Good evening. It's a tribute to Canada. Bonsoir. Bonsoir to, yeah, say the end, we're doing good. My name's John Foudier, that's the French version, but I go by Furrier. Great venue. What do you think? It's beautiful and there are many rooms. I mean, for once at an OpenStack Summit, we can get rooms, we can get small meetings, and that's great. We're right on the water, the weather's perfect, planes are landing. It's a good vibe for OpenStack. Talk about what you guys are doing with OpenStack. What's your take on Scalely, OpenStack? Your role in the community, share with the folks out there Scalely and context OpenStack. So we believe that a few years from now, five, 10 years from now, the people running infrastructure will run infrastructure at large scale. If you have a small scale system, you'll just outsource it to the cloud. You'll use a cloud service, whether it's Salesforce, Box, or Office 365. So people running infrastructure will be doing that at large scale and they will be doing this in an architecture that is essentially software based. We need a place for the different software components to be able to talk together, to find how to interface with each other. We're all building this future together and OpenStack is the place where to meet, where to discuss, where both the development community, whether it's commercial or open source, and the users can come, mingle and create the future. I was talking with Jonathan Bryce early in this morning and then we had Sam from Cloud Foundry on and it's interesting, we're in this build out mode right now, heavy duty building out, a lot of builders. But it's under a lot of pressure with cloud to build fast because of the competitive pressures one, two, and the demand. So this comes back down and one of the comments was the ops guys are feeling left behind because the development focus has always been okay, front end, apps, apps, apps. But at the end of the day, you got to run this stuff on infrastructure. Yeah, I think it's a realty that we're all trying to go as fast as we can and in some way we're all behind. I mean basically Google, Amazon, Facebook have led the way by doing it and kind of doing it in the secrecy of their own data center and making it known to the world that it's possible to do it. And since then, everyone's like running as fast as possible to make it a realty for the enterprise world. And really it's a case of the glass half full or half empty. You can say we're not going fast enough at the same time. I mean we've got dozens of customers. We computed that Skillety is powering storage for 300 million users on the planet. I mean it's already a huge number. Yeah, storage is not going away, that's for sure. There's already millions, hundreds of millions of people using the things that we discussed here. So we had a crowdsource conversation. I want to share with you the top conversation. I want to get your thoughts on it. The conversation was taming the data dragon because you mentioned storage. Storage is not going away around high availability. The number one discussion point was how important is your data be available at all times? How do you balance cost versus availability? What approaches to high availability do you think work best? This generated the most conversation. So what's your take on that? I'm asking everyone, why is data available at all times? It's kind of become a cliche. Well, so I think it should stop being a conversation. Availability, high availability, working 24 by seven. Life patterns, work pattern have changed. People expect to have access to their information. And you know, this is now the continuation of my brain. I can't live without it. And wearables, and internet things, sensors. It's all going this direction. So we expect access 24 by seven every day, even on Christmas day. Skeleton towards that, we offer SLAs. If it's not available, we pay our customers back. It's as simple as that. Our first customer was live in 2010. That system never went down. I mean, when I say never, I need not one minute, not one second. It's been serving for zero down times. Yeah, 100% zero downtime. You're saying that. Exactly, and that should be a de facto issue. What was the scale of the application? Two million users. So it's real. So it's a real app. Real workloads, it's a workhorse. Yeah, it's not like it's like a mobile app for sales. People dial in. Two million users daily. If it didn't work, you would see it on the newspaper. It's that kind of app. So high impact? Yeah. If it went down, there'd be disruption. Totally. So, I mean, very real. Same thing about data protection, by the way. I still hear a conversation about data protection. It should not be a conversation anymore. I mean, there's enough technology out there to protect the data very well. And we offer durability SLA, where if we lose any piece of data, which really never happens, that's why we're willing to pay our customers back. And we never have. Well, hold on, let's drill on. What does durability mean to you? Because durability is a great word, building a durable company, having a durable product. But you have a specific SLA around durability. Explain that concept. So here we talk about data durability. When we store our idea of storage, it's that our business is to make your data secure and to guarantee you won't lose it. I mean, isn't that what we call storage? So we think it's pretty basic. And we think that if you're playing in the storage world, you need to keep that as secure. So we're convinced of that. We're developing technology for that. And we're paying out if we miss our target, which honestly never happens. Yeah, and so you get backed up with warranty and whatnot and guarantees in SLA and a service level agreement. Yes. All right, so what do you think about like ExtremeIO with EMC, obviously a big seller, a lot of traction, SSDs are hot, obviously Flash is obviously people going that way. What's the balance between Flash, spinning disk and tape? I mean. And that will change over time. So basically there's data that is very latency sensitive and today it should go on Flash. Flash is the best technology for that. It's less than 20% of the data. And for that data, it's extremely valuable to go to an old Flash array and ought to have an hyperconverged system. And then there's 80% of the data where it's still very performance sensitive, but it's not so much latency sensitive. And here when we talk about latency, there's a difference between a machine to machine application, machine sensitive to microsecond. And a human is sensitive to about 50 millisecond. A human doesn't notice anything smaller than that. And for anything, the 80% of the data essentially is not so sensitive or latency, but still needs a lot of throughput, for example, like video application. This is very well on hard drive. You just need to have enough hard drive and this is where a big scalable platform makes sense to be able to serve the performance. So you guys are doing pretty good. Business is good. We're doing over 200% growth year over year. We're doing good. And you have a relation with HP and others. We have a distribution agreement with HP which we announced last October. It's producing deals. We covered that. Yeah, cute conversation, of course. It's producing real deals, so we're very happy. Is it joint sales or just go to market together? It's actually HP Resale Scology. Okay, so they are actually taking your product to market. They created SKUs, they can resell software. Was that new or is that part of the deal? I can't remember. That was part of the October deal, yeah. That's fantastic. So yeah, that was a benchmark. Sales are up. Absolutely. They buy you? Are they going to buy you guys? I think they're happy we're happy. Everyone's happy, money's flowing off the tree. So I got to ask you about petabyte scale. How do you simplify stuff at that level? Zetabyte scales next after that? Simplicity's number one on everyone's mind. Absolutely. So talk about that. What's your vision? So I often say jokingly but only half jokingly that what we sell is peace of mind. When we deploy it to customer, he can sleep at night. He doesn't have to do his maintenance at night. Our system handles disk failures. You don't have to wake up for a disk failure. And basically all IT industry is about automation. We automate the complexity of handling large scale storage. And now it's our software that's responsible for the complexity, not the human. That's it. Yeah. I mean, I can go into gory technical detail but fundamentally that's it. That's what we do. We sell simplicity. Okay, so I got to ask you a final question of the segment and thanks for coming on. I know it was last minute. You got your stuff came right from the plane. It looks like you just got in town. I appreciate you spending the time to share your insights. Moving forward, what are you looking at? What's on your chessboard? What are you monitoring? What are you watching in the landscape that as CEO and also technologist, because you are doing so well right now, market shifts very fast. We have no idea what's next in the innovation cycle we're seeing, a lot of dynamics, a lot of pressure. So to go from petabyte to exabyte and zettabyte, we need to get better on power consumption. So all technologies that free five years from now will be able to store with less power consumption are interesting to me. There are the new IP drives from Seagate. It's an example of that. Another example of that is some flash technologies that you can power off and still remembers data. Anything that's going to be about very large quantities of data that are stored without requiring electricity. Final question, open stack. What's your take of the community? Where do you need to see it go? Are they doing okay? Are you giving them a good grade? Do they pedal faster? Is it going too slow? A good, bad, ugly. What's your take on open stack? Where's it going? I think open stack is an organization that is seeing growing pain. And we all always say that growing pain are a good kind of pain, but they're still pain. What I'm seeing, summit after summit, is a community that is maturing. Maturing in their communication, maturing in their technology savanness, maturing in their experience. I think it's all going in the right direction. Could they go faster? I think it would be unrealistic. So I think it's the rest of the industry to essentially go at that pace. Well, merci for joining us on this CUBE interview. Thank you very much, as they say in French. This is theCUBE. We're here with Jerome LaCotte from Scality. CEO, doing great. We had him on theCUBE before with Leo. We had some crowd chats. Join the conversation on crowdchat.net and here in theCUBE. We'll be right back with more after this short break. Thank you.


In turn at the Center for Law and Democracy, because I've always been interested in human rights law, and that was definitely a factor for my decision to go to law school. So I thought this would be a really great opportunity to actually experience working in this field of law and working in that type of environment. My day-to-day work involved doing legal research. That was the main role that I played was providing supportive research to my superiors, so the executive director of the Center for Law and Democracy, and the main legal researcher. So depending on what projects we had each day and what issues had arisen would be the type of research I would do. This would vary from responding to a new law passed by a country. I would assess that law and then write up a comparative analysis of that law to the international standards that we were trying to promote. This would also involve doing research on specific human rights terms or issues that could be used within a paper or a report that the Center for Law and Democracy was publishing. So every day was kind of different in the stuff I was researching and the issues, but it was a very research intensive internship. The first larger project I worked on was drafting an editorial charter for Myanmar's public broadcaster MRTV. An editorial charter monitors and sets standards for the behavior of public broadcasters. So in drafting this for Myanmar, I first looked at the editorial charters of international public broadcasters, so including CBC, BBC, the public broadcaster in India and South Africa. And then from there, I worked with other interns at the CLD to draft provisions that were specific to Myanmar's context. And then once that was finished, it was submitted to the government in Myanmar to approve and implement, which is still ongoing. The second larger project I worked on was researching on how Nova Scotia's Cyber Safety Act could be drafted to be more constitutional. The act was found to be unconstitutional because it infringed on people's freedom of expression. So I did some research to prepare for the Center for Law and Democracy's involvement of discussions with the Nova Scotia government by researching what the problems were with the old act, how it could be drafted so that it was more constitutional in the sense that it didn't infringe on freedom of expression, as well as researching other jurisdictions laws on cyberbullying and how they've approached the issue, including in Australia and in the United States. Because the internship was focused on legal research, I found that legal research and writing, which I took in first year with Ann Matthewman, was especially important for me to be able to accomplish any of the work I did. That course allowed me to learn how to use legal resources such as Canly for doing research, as well as how to cite legislation. So that was really important for me to be able to accomplish any of my research tasks during the internship. I also found that constitutional law, which I took in second year with Professor Elaine Craig, was really important because it provided me with knowledge about the constitutional right of freedom of expression.


So let me introduce today's speaker, which is Simon Knoijer from the Udresden. He will talk about network satisfaction for symmetric relation algebras. It's yours. Thank you, Jakob. So this is John Drog with Manuel Budijewski. And I would like to start with an overview of what we'll talk about. So I will introduce a class of computational decision problems to you. They are called network satisfaction problems. And the result of our paper is a complexity dichotomy for this class. So the way we obtain this result is by a connection to infinite domain CSPs. And I will show you this connection and also will give you some details of the proof. From the CSP side, what we used is, of course, the universal algebraic approach to finite as well as infinite domain CSPs. So this is precisely dichotomy theorem by Andre Bulato for conservative CSPs from 2003. And more on the infinite domain side, we use a Ramsey type theorem by Hubek Knoijer. Okay, let's start with an example of a problem in our class. And therefore consider a finite set of integers and think of them as distances. So one to five as distances in the plane. And now there's a computational problem that is given a graph and undirected graph that is labeled by subsets of the set D. So for example, one for five at this edge here. And now the question is, can you choose for each edge and distance that is given in the label set such that all triangle inequalities hold on all triangles of the graph. So what do I mean with triangle inequality? Of course, the label of an edge from A to B should A to C should be less than the label from A to B plus the label from B to C. And we think of them as distances. Okay, how could this look like? We choose this assignment here. And now we have to check, are all triangles, is there a sign for all triangles compatible with the triangle inequality? For example, here we have three, four, five. So all possible triangle inequalities hold, of course. Another triangle in our graph is this one. Also here you can check this is fine. There's the last one, and this is this. Here we have, of course, that four is not less or equal than one plus two. So this was not a good choice of distances. And yeah, you can see that there's also no better choice. So this is instance we would recheck now. Okay. So this was an example in more general. Can I, what are you with a simple question? Do you also care about like longer cycles? So if you have a graph that has no triangles then. Only the triangles, only the edges of the induced triangles of edges. Okay. So in general, we have this finite set D and inequalities we formalize now more general in a set B that consists of at most three elements subsets of D. And now the problem, which is generalization of the example from before, network satisfaction problem of DB. We have given an undirected graph G with edge labeled by subsets of D as before. And we ask, can we choose from each label and element such that now on each triangle, the three, the set of the three elements is in B. Yeah. So how now let's try to match this with the example D is the set of distance one to five and B are all subsets XYZ of D. We're all trying all possible triangle inequalities. And for the instance that we saw before, you would now check, okay, for the first triangle, three, four, five is in the set B. As well as two, four, five is in the set B, but one, two, four is not in the set B. So in this sense, we reject this instance or we would reject this assignment. Okay. And now our result is for classification of complexities for problems of that form. And the classification is that they are polynomial time tractable or empty complete. And additionally, we can give them DB. So this, this table DB, these two data types, it's decidable which of the two cases holds. And of course, this means that there are no NP intermediate problems. And one could see this result as a partial solution to a question by Robin Hirsch. And he asked, can we point out all the P time tractable network satisfaction problems of relational algebras. And he called this problem the really big complexity problem. So, of course, there's now the question what have these network satisfaction problems of relation algebras to do with the class of problems that I introduced. And therefore, let me give you a very short intro to relation algebras. And they are basically sets of binary relations. So think of them as a finite set of possibly infinite binary relations that are closed under union intersection and relational product, the binary relational product. They are used to model temporal and spatial reasoning problems and AI and some examples that you might know are Ellen's interval algebra point algebra and read you connecting Calculi like RCC five and RCC eight. So the history of study of relation algebras started with Tarski and some other names Hodgkins and Maddox. What what's important for us is that every relation algebra has well defined network satisfaction problem a computational problem that is called network satisfaction problem and decision problem. And the complexities for such problems in this. Yeah, for for for relation algebras are only partially known so only for some examples like basically the names that I mentioned before so ends interval algebra point algebra. There are 18 small relation algebras there the complexities known and maybe interesting there are also examples known for finite relation algebras with an undecidable network satisfaction problem so it's not the case that we are always in NP for in general for network satisfaction problems. And in this sense, our result can be stated as classification of network satisfaction problems of symmetric relation algebras with a flexible at so only for the context of the title and some motivation of this work. But this is all about relation algebras because we would like to see something about CSPs and therefore start with some basics for for infinite domain CSPs. And here we start with set F of finite finite set F of finite relational tau structure so tau is a finite relational signature and B is a possibly infinite tau structure. And then there's a class of finite tau structures for of F and these are all the finite tau structures that do not embed any of the structures from the set F. And for example, you can think that F could be the K3 the complete graph on three nodes. And then for both F would basically all finite graphs that do not embed and trying that do not have an induced triangle inside. As some example. On the other hand, H of beam are all the finite tau structures that embed into the possibly infinite structure B. And we call the structure B finitely bounded if there exists some finite set F such that H of B is equal to four both F so we can describe the finite sub structures of B by means of a finite set of forbidden structures. Another important notion for infinite domain CSPs is homogeneity and this is that every homomorphism of two finite sub structures of B can be extend to an automorphism so whenever you see two pieces that are isomorphic in your infinite structure you can shift them by a global automorphism of the whole structure. And, yeah, there's an important property for classes of finite structures amalgamation property that is in connection to homogeneity of the infinite structure. So what about what's amalgamation. For any three structures a B1 B2 such that a embeds into B1 and B2 so you can think of, and we have two structures B1 and B2 and they have in common overlap in the structure a. Then there exists another structure in your class, in this case forb of F in forb of F such that you can embed B1 and B2 together in the structure C and this behaves well with the structure a so in formally we have this commuting or this equality here. And now there's a connection between dimension connection between homogeneity and amalgamation property by fascist theorem. And we get that if a class forb of F has amalgamation property then there exists a unique countable structure such that the age of this structure is equal to forb of F and the structure is homogeneous. And we will make use of this theorem. So, therefore, CSP of an infinite structure are all finite structures that have an homomorphism to be. And the observation that we use is that for every MSP there exists a finitely bounded homogeneous structure such that the network satisfaction problem defined on, yeah, is equal to the CSP of this infinite structure. So this is basically the core of this motivation or this connection between network satisfaction problems and CSPs. So why is this? How do we get this? We think of D, so D is the set of distances you can have in mind as a relational signature with binary symmetric symbols. So distance is symmetric and they are binary. And now we define the finite set of finite D structures as follows. All two element structures with more than one non-empty relation. So all things like this where you have two different distances between two nodes. So distance one and distance two and all, yeah, also if you have three different distances and so on. Everything that is not exactly one distance. And moreover, we have all the three element structures that induce a triangle that we don't like, yeah, in terms of the set B. So the labels are not in the set B. Now, of course, whenever I write such a picture and talk about now the D structure, so the signature is D, then with the picture I mean that these two elements here are in the relation four. And now the class four of F has the amalgamation property. And this is relatively easy to see because whenever you have such a diagram here, so two structures B1 and B2 and something in common. And if you don't have a bad triangle, then it's fine to basically draw, take this structure that you see here as the amalgam. So you don't have to put new relations and this is fine to have some free amalgamation. We call this. And by Francis theorem, of course, we have an homogeneous structure B prime with a B prime is equal to four both F so by applying the theorem. And as a last step we extend B prime by all binary first order definable relations so we take all the unions of the relations more or less of our signature and extend our signature such that we have all of them in our signature. And now what's why is the network satisfaction problem of this table DB basically the same as the CSP of the infinite structure be now up to some rewriting of signature so start with an instance of the network satisfaction problem looks like this. And now we add new edges and new relations with a new symbol F and this new symbol F means that two elements in the structure B are in no distance of the set D. So, of course, it could be or it's yeah, there are elements in the infinite structure be that are not in any of the relations named by the set D, and this new relations so no distance is denoted by F. So free or flexible or whatever you want. If you now change the this point of view that the label on this edge means these two nodes are in relation to or for then this is precisely a structure in the same signature SP. And it holds that this is also in the CSP. So it's also an accepted instance if the former was accepted. Okay, and for the rest of the talk I would like to call such structures be such infinite structures be in the class FA for flexible atom or pre amalgamation whatever. Yeah, yeah, that arise from such a data type DB SS I out you in this observation. Okay, so now I can give you a second version of our result and always have in mind so the infinite structure be has some some guys connected to this data DB we will make use of this and then. Now we define a finite structure called the type structure of be or maybe also type structure of DB one could say, and the domain of this finite structure is the set D together with two new symbols and one of the symbols you already know this is the symbol for the no distance integration in the structure be and a symbol it for identity and we put in this finite structure or finite all subsets as you know re relations and internally a relation where XYZ is in age if one of the three options here hold so first of all. The set XYZ is a good set in our in our data set be the second option would be the it element is not in the set but f is there and then we also have a have some some good table and XYZ is in age and the last option is that there's. One identity element and only one other element at most one other element so this somehow. Models now a triangle where one one edge has an identity label then the two other edges should be the in the same relation but we'll make this clear in the following and. Okay, of course, figures polymorphism for the finite structure D is a homomorphism from the six power into the structure itself with this identity here and the second version of our theorem would be for every infinite structure in this class FA so. Given by such tablets DB then the CSP is polynomial time tractable if this tight structure D of the structure be has a figures polymorphism and otherwise it's anti complete. And okay, of course, the structure D is finite by definition and there are only finitely many homomorphisms for on the six power so you can decide whether D has a figures polymorphism and this proves this more over part of our theorem that it's decidable which of the two cases. Given that this theorem is true. Okay, how do we get how can we prove this so be is in the class of a and the first observation is that the CSP of the structure is an empty so this is basically because be is finitely bounded for finitely bounded structures you can. Guess relations that you have to add and after guessing you can check polynomial many situations if the bounds are there or not and recall that we have only a finite set of bounds so this is clearly checkable in polynomial time if you get. And the first non trivial step is that for this finite type structure D there's a polynomial time reduction from the CSP of P to the CSP of D. And of course if this is true then we can use the CSP dichotomy for for finite domain CSP is and if D has and signals polymorphism then. The CSP of D is in P by the dichotomy and in fact we don't use the full strength of the dichotomy but only for conservative finite domain CSP is. And of okay if we haven't P time reduction then this immediately implies that we have that the CSP of B is also in P. So. The second big step is that we assume that D does not have figures polymorphism and then also by the dichotomy we get that the CSP of D is NP complete. And main part of our work is to more or less prove that there's a reduction from the finite domain CSP to the infinite domain CSP and this is. With the help of Ramsey type theorems as I mentioned by who which kind of children and others. And then we would have that infinite domain CSP is also NP complete. So let's have a look at the first and the easier case about tractable cases and as before we are in the same setting and recall the type structure we have this domain. Which is the set D together with these fresh symbols and we claim that for B in the class FA then there exists a polynomial time reduction from the CSP of B to the CSP of its type structure. And this is done by the following reduction. So this instance of the CSP of B recall we added these these new edges and labeled them by F and say these two do not have a distance. And now we reduce this and so first of all we add for each edge in this graph here new variable and index correspond to which edge. Then I put these red bubbles here for each triangle. So whenever the three edges now build a triangle then they are in the in the relation H. And of course we have four of them. And the last step is that we add for each the relation of each edge here so X2 and X3 are in the relation two or four. And this is now a unary relation at this for this variable two three and also for all the others. And this reduction works and is straightforward to do this like this. Now the second step for this tractable cases is of course that we use the dichotomy and I will call a finite structure now conservative if all subsets of A are unary relations. So this may be not totally common to have this notion for structure this bus of course compatible with the notion of conservativity for clones or. And then of by definition the type structure D is conservative. We put it all unary relations in this structure. And I would like to remark here that there already existed a notion of type structure introduced by police can one day. And this finite type structure was used in exactly the same way we used our type structure for reducing the infinite domain CSP to the final one. And yeah in a in a very nice way but this final type structure of police can one day would not be conservative and our type structure is conservative and this is what we heavily will use in the hardness proof later. Okay and of course for conservative structures we have the dichotomy now yeah in this version here so which is maybe not the original one. But if we combine this with our reduction from before then we have that if the type structure has a secret spot in office and the CSP of B is in P and this is everything for the algorithmic side of our result. Okay so let's have a look at the second the hard cases. So also here I would like to start with some definitions and therefore okay polymorphisms of B are all homomorphisms from the and power of the structure into the structure itself for any M. And we call and polymorphism canonical if for all tablets x1 to xn from the structure B and all automorphisms alpha one to alpha n. There exists another automorphism beta such that whenever you first shift the tablets x1 to xn by the automorphisms and then apply f it's the same as if you apply f directly on the tablets and then shift it by the automorphism. Okay, in other words this means that canonical function in induces a function on an n-ary function on the set of orbits for all m-orbit so for all orbits of the action of the automorphism group on n-tables of the structure B. And there are some observations so our structure B is homogeneous and only has so all important relations are of arity 2 and this means that we don't have to care about m orbits but only care about two orbits so orbits of tablets of length 2. And another thing is that the two orbits can be identified with the set D star so this is basically because this is the why we choose to set D star in this way. So D star was the domain of our type structure and we have that all the elements there correspond to the relations to the basic relations in the structure B and in this way we get a one to one correspondence of the orbits of the infinite structure and the elements of the finance structure D star. And most important we have the following if polymorphism of B is canonical then this induced function on the orbits which is an induced function on the set D star or an n-ary function on the set D star is in fact a polymorphism of the type structure D. And this is also true in some sense in the other way whenever you have a polymorphism of the type structure D you find an infinite and polymorphism of the infinite structure B that is canonical and that induces exactly the finite operation on the finite domain with which you started. Okay, so last definition here, I would like to read in this notion of canonicity a little bit and this is for two elements A and B of D star so basically two orbits of our structure.  If the same holds, if we restrict ourselves to tablets x1 to xn from the set A or orbit A or B. So, this is not all orbits now, but only two, but also the same holds. So, if we shift, so we stay in the orbit by shifting of the automorphism and then apply F then this is the same if otherwise you would start with applying directly on the tablets x1 to xn the operation F and then shifting with the automorphism better. Now, such an canonical AB canonical polymorphism does of course not induce an operation on all the orbits, but on a subset of orbits on the subset AB of two orbits in this case. And, okay, one thing that's important here that it really induces an operation on the set on this subset of orbits is because we are the structure B is closed and all binary first order definable relations so the polymorphism that that preserves all these relations has to put in, if all its inputs come from orbits A or B, then its output also is in the orbit A or in the orbit B, because the relation orbit A or orbit B is preserved by all polymorphisms. This is why this is really a function on a subset of two orbits. Okay, and now for another time the conservative CSP dichotomy but now more technical and we have that for finite conservative structure then either there exist two elements in the domain such that all polymorphisms, the restriction of all polymorphisms on AB to the end is a projection and then and the completeness or hardness follows, or on the other side, Paul of A has in figures operation as before. But what does mean, we are in the case that the polymorphisms of our type structure D do not contain in figures operation. However, we have that there exists by one two elements a star B star in D star, which is the domain of the type structure such that one is true. And this is now the starting point for our hardness proof so all things that we collected now so DB where our data is in the infinite structure B, the finite structure D and two elements from the domain of the of the structure that have this special property from from before. And now the first step is that we prove that if B does not have a binary injective polymorphism, then the CSP is hard. Okay, this is basically what we would like to prove in general here in this in this part in this hardness proof, but it's a little bit easier under this assumption. This is basically because the element it in our in the domain of the structure D is somehow independent of the data from DB, because we all in all cases. Whenever you have another another another DB table, you add the new element in the same way. I mean the definition stays the same only. And the second step is that if B does not have does have a binary injective polymorphism then it has a canonical binary injective polymorphism. And for this step we use their Ramsey theory. Next step if this implies that it the element it is not part of a star B star, because otherwise on the induced function. And if the polymorphism F is now canonical then it uses a function on the orbits. And if it is on the other hand injective this means that the induced function is symmetric for all all sub algebras it X in D star. Because injectivity means whenever your input is it or X the output is not it because this would contradict injectivity. Okay, so it is not here. And next step is that we show that if that B does not have an A star B star symmetric polymorphism and by this I mean an A star B star canonical. So it's not canonical in general but canonical on on the orbits A star B star and the induced operation on A star B star. Think of it as a partial function in on the type structure is symmetric is binary symmetric. And again here there is heavy use of the Ramsey theorem. Step five.  And if this holds for all polymorphisms it's relatively easy to see that the CSP of B is then hard because there are not so many cases that can apply. And you can again use the Ramsey theorem and get that this would contradict your assumption about the elements A star B star in the type structure. So six is not not not very hard. But the most interesting step is so this number five. And this is what I would like to show you here. The rest of the talk and in step five we would like to prove this proposition.  So in other words assume that B has an injected polymorphism and does not have an A star B star symmetric polymorphism. Then we get that all polymorphisms of B are A star B star canonical. Okay, and we start with the negation of two and we use this lemma which is inspired by a work of Woody's can Pinsker. And it says that when for all elements a B in our in the domain of our type structure or you can also think of a B as two orbits, then B has an a B symmetric polymorphism and the induced function on a B. A maps tablet a B to a and B a to a, of course. This is equivalent to that every primitive positive formula find that satisfies that has four free variables and it's satisfiable with relation a on the first two variables and relation B on the second two, as well as relation B on the first two and a on the second two. Then we get that phi also satisfy a on the first two and a on the second two. Okay, and okay, of course we do our assumption is that we do not have an A star B star symmetric polymorphism. The two options is not a star B star means not not mapping both to A star and not making mapping both to B star so we get two formula. Phi A star and Phi B star. And they have the properties that are mentioned here in two of the lemma. Okay, and now we use these two formulas, Phi A star and Phi B star to define a new formula file. And by the following so in my picture I denote. Yeah, variables are the nodes here and the small edge is the relation after the free relation the flexible relation dotted line is a star and the full line is B star. So we have a formula phi A star that isn't for every formula or for three variables. And we know that it's possible to have this configuration so a star in on the first two and B star on the second two. It's also possible to have B star on the first two and a star on the second two but it's not possible by definition to have a star and a star on the first and second two. And that holds for the formula Phi B star. This is possible, this is possible, but this is not possible. And now we build a new formula file. And this is done by the following the three variables are the top and bottom x one x two and y one y two and all the other points here are existentially quantified. Okay, the relations between so the three variables are always relation F. But if we define this in that way then we have a nice property that if you start with a dotted with a full line here in top, then by the green bubble here we get that here. And we cannot have the full line so then in some sense there needs to be the dotted line. And now we apply the red bubble and we get that there cannot be the dotted line so there needs to be the full line. So we have full line here. And again the green one and we have that whenever you start here with the full line you have the dot line here. And this works also in the other direction if you start here with the dotted line and you get by red, the full line dotted and full. Okay, so we have full line if and only if dotted line here and also in the other way around. And the key thing here is that the relation F and the existence of an injective polymorphism ensure that this formula fire is really set up. And this implications always mean if if there is some type of then it has this property, but the main things are the power of our setting here that we have this relation F and the injective polymorphism and ensures that such topics exist. This is important. And with this formula five we can now define a new formula q equivalence, which is also for every. And so this is straightforward we get that we have on the first two coordinates a star if and only if there's a star on the second two coordinates, as well as B star if and only if B star on the first and on the same. So this is now very, if you have to find and this is easy to get. And what's also easy is that if such a relation is pp definable and therefore preserved by all polymorphisms. This means that all polymorphisms are a star B star canonical so you can take the the preservation of this of this relation also as an definition for for a star B star Okay, and so this was all basically what I want to talk about. Let me finish with last sentence so our work also confirms the so called infant domain tractability conjecture about reducts of finitely bounded homogeneous structures. The class FA is a small subclass of the class of all reducts of finitely bounded homogeneous structures. And, yeah, in this sense, and one thing that would nice in the future of course classify more general classes of network satisfaction problems. And from the relation algebra on what Asian site is one possible option could be to drop the symmetry assumption so all our relations that we did with were symmetric and would be also interesting to have directed edges directed colored edges in some sense. Okay. Thank you for your attention. Yeah, thanks. Thanks for a very nice talk. The questions comments. Now you cannot see my screen. No questions. Well, maybe I can ask a question. Yeah. So Simone, you were mentioned in the beginning, some really big complexity problem. As it was called by Hirsch, but it's not maybe immediate to everybody. Well, not immediate to me why it's so really big. Could you say something about this. So, yeah, I mean, so this this question has different levels and there's one level that I would call not not not very easy for for our infinite domain perspective. And this is only a subclass of relation algebras where we already already don't know a classification. So this is not the full problem of Hirsch seems already relatively hard to solve with with our, I would say advanced tools for infinite domain CSPs. But in general, yeah, there's, I don't know that in general you cannot apply the infinite domain CSP stuff or theory. And there, I think there are no, no ideas how to do this in general, or if there is even a possible classification in some sense, I don't know. Maybe. Okay, thanks. It's just a hard problem. Maybe I will have a question as well. So you at some point you compare to your type structure to to that of Anton. So what is exactly the difference between the two. So basically the airity of the tuples that you would take so so in the type structure of manual and on one you would in our setting since we have bounds of size three so we forbid structures of size three. And we would need to take tuples of size three and look at the orbit structure of these three tuples. And of course, the conservatility only applies to the two tuples, because they are the part of our signature and if you would have your your type structure on three tuples, you are not long on conservative and Yeah. Okay, so, so it's like, basically just you are restricting the RAT to two and that makes And then you also have to be careful because if you have the higher airity then you there's no need to have this relation age you you can choose other relations that encode the structure. So the good finite structures in your infinite structure be. But if you are not on the three tuples, then you have to add something different to to to to, yeah, to ensure that this correspondence of polymorphisms hold so that the behavior of the canonical polymorphism is a polymorphism of the type structure. And this is why there's no relation age in the type structure of on 209. Okay, thanks. Some more questions. So, sorry, so is it that the two types of type structures are essentially the same like up to BP into the finality or something or what's what's the exact situation. Up to the interdependent. I just might be. Yeah, I don't know could you but I mean they they should have the same same polymorphisms right to the polymorphisms are just the like, yeah, yeah, yeah. Yeah, yeah. Yeah. Yeah, you're right if you go back to the canonical clone then this might. Another question. One last to ask one last opportunity to ask a question. So, yeah, I wanted to ask so does the ground theory of approximation simplifies things here. Yeah, I think this is true. I think. At least the first step. I mean, yes, the general feeling is that this should simplify most of this. But this is not not checked yet. But I think the maybe this first step in the hardness proof so going to infinite going to the injective. And so, okay, this is not really the theory of smooth approximations but you can find some nice lamata in the paper and there are definitely some things to do better and easier. And the general feeling is that, yeah, should be simplified. Okay, cool. Thanks. I mean, in your case you have this unique interpolation right. So like when you want to extend this clone homomorphism say that you can just take some function which is interpolated by some canonical function and consider the image. But in your case it's it's kind of happening in the sort of obvious way right because you have the same behavior on that two elements that you already have the some behavior realize that so. Yeah. Okay. Okay, so let's thanks again.