Hi everyone and welcome to this session on scaling up without slowing down, accelerating part start times. We're so excited to see so many of you here today on this Friday afternoon and seeing this overflowing room is really thrilling. Thank you so much for joining us. I'm Ganesh Kumar Ashoka Vardhanan, a software engineer at Microsoft on the Azure Kubernetes service team. I work on Node Life Cycle and GPU workloads. I also developed this feature called Artifact Streaming, which speeds up part start times on AKS in close collaboration with the Azure Container Registry team. With me today is Yifan Yuan from Alibaba Cloud Storage team, and he's a major maintainer of the Ovalabd open source project, which we use for AKS and many other companies use as well. Have you ever had the situation where you're waiting to book tickets for your favorite concert or sports event? Maybe it was a Taylor Swift concert and you go to the website and you're trying to book the ticket, but the server crashes or you're not able to log in and make progress. That's often the case when you're trying to suddenly have many people book on a website or the load increases a lot. And that could be because of many reasons such as network congestion, storage throttling or issues with containers being able to make progress and crash roof backups. It could also be due to slow node scale up. That leads to a poor user experience and a developer experience. So in this presentation, we're going to talk about the common approaches you can use to speed up part starts, explain why part start takes so long. And we'll also share high level approaches to reduce part start time and talk about the challenges that happen at scale when you're trying to scale up quickly. We'll also show a demo with a challenging LLM based workload and also talk about our experience integrating this in production and the various state offs that we have to consider. So what are the common approaches to address this problem? Most container run times like container D already have a feature called layer sharing. As you know, a container image is made up of many layers and these layers need to be pulled and decompressed. If the layers are already present on the host node, then container run times like container D don't need to pull it again. There's another option through Kubernetes from KITS 127 and there's a flag called serialized image pull. And if you turn that flag to off or false, then you can parallelize the pulls on your node. This is especially useful in cases where you have multiple pods scheduled to run on the same node and you need to make progress simultaneously. The other approach that many teams use is to reduce the image size. They carefully look at the Docker file to reduce dependencies or they use tools like Slim Toolkit to reduce the content in the image programmatically. For teams and products which are very latency sensitive and you are okay to bear additional costs, then the approach is to pre-download the images on the node itself. This is known as having warm nodes and what this is is you create extra nodes in the same node pool and then schedule with CRDs like the open-crew CRDs to download the image before it's needed. And then when your replica needs to be scheduled on that node in the future, that already has the image pulled and you don't need to pull it again. This will reduce the time significantly because the image contents are present already on the node, but it also increases your costs. So the only thing accelerating in that case would be your cloud costs or your compute costs. And that's even more important in the case where you have GPU workloads because GPU nodes are hard to come by and they're very expensive. So maintaining this warm pull is hard in terms of scalability. So why does it take so long to start apart, especially when the container image is large? Most of the time is spent on the image pull phase. As you can see for this 1.3 GB image, a significant fraction of the time is just spent on downloading the image content and decompressing each of the layers and less time is spent on other steps. There's research that's also found that only a small fraction of the image is needed to start. There's a paper which showed that about 6.4% of a container image on average is needed to start running a workload and doing meaningful work. And in some of these examples too, we see that only a small fraction is needed to get to a ready state. This is the core observation that many open source solutions use to address this problem. So you can download what data is needed when it is needed. Open source projects like OverlayBD, Sochi, Nidus and E-StarGZ are some of the main projects that address this problem. And the main differences between these projects are the type of block device or file layer that they access and the way the image is converted and the decompression algorithms they use. But all of them rely on this core insight. So in AKS we use the OverlayBD open source project and this is a container D non-core project and it integrates well with the container D snapshot or the remote snapshot of a container D. OverlayBD stands for Overlay Block Device and it is a layered block device image format which allows for seekable online decompression and provides layers as a sequence of blocks through a virtual block device. And the decompression algorithm for OverlayBD is also much faster compared to the GZP decompression. And application system calls are translated essentially to remote calls through OverlayBD when they are needed. So this is done purely on demand. This is a diagram that can illustrate the various steps involved but we won't be going too much into the details because there's also a paper which explains each and every step of this. So when we try this on AKS, we noticed that the pod starts significantly faster. So as you see when you have a larger container image like a 6 GB image, it takes several minutes, six and a half minutes or so to start for an OCI image because it needs to pull the entire data. But for an OverlayBD image it starts instantly, almost instantly. The main caveat to note with this is that the start time here refers to the time it takes to pull the metadata related to the container image and it downloads minimal amount of data to set up the necessary components for OverlayBD. To know the accurate start time, the realistic start time, we also need to set up readiness probes that capture the true state of what needs to be ready before it started. So one of the challenges during scale up is you need to read significant data in many cases. So in this example we had a readiness probe set up that is ready only after one GB of data is read sequentially and we use OverlayBD for this case. But the first pod start takes a long time. It takes about three minutes to start running the pod. And that's also because of throttling from the registry side. And then you also see that there is a significant time when there's not many pods are getting ready. And that's because of significant network congestion and storage throttling with, you know, a thousand pods attempting to pull at the same time. So we're going from zero to thousand. And this graph will look different based on the registry and internal operations happening in the background in your cloud environment or your on-prem environment as well. So for the large language model case, which is becoming increasingly interesting for many people, we also did an extensive study. So LLMs you can think of as being made up of a series of giant matrices that convert an input text, which is converted to a vector format. And that undergoes a series of operations to get an output vector format. So all of these giant matrices need to be in memory before you can do any inference work. So for this experiment, we tried with a Falcon 7B inference workload, which is based on the Kaito framework, which we mentioned in the keynote a couple of days ago. So this Falcon 7B is just an LLM with lots of parameters, but it's one of the smaller LLMs. So for an OCI image, when you have it in the container image, it takes about five and a half minutes to start running this workload. But with pure on-demand image loading, we were curious to know how long it would take. And we saw it took seven and a half minutes, which is really disappointing. And as you can see from this, most of the data in the container image is for the model and most of that is needed at the very beginning. And that offers you some clues as to why this was slow. Now my co-presenter Yifan will share about how we can improve this and the other approaches we can use. Thanks, Ganesh. Next part, I will show you some solutions for these scenarios. First is P2P. P2P technology can be used to reduce a lot of registry and speed up the time of image pooling. Only a few nodes download data from the registry directly, and the rest will get data from other peers. There are some open source P2P projects can be used separately with pooling OCI images or with streaming OCI. Korgan is a P2P-powered Docker registry that focuses on scalability and availability. It's designed for the Docker image management replication and distribution in a cloud environment. Dragonfly is a great project that has been around for a while. However, it covers many complex cases that require additional dependencies like Redis and Mexico. It will consume more resources and results in a managed additional resources for the end users. Special is another open source P2P project which focuses on solving a smaller problem with fewer features and complements than Dragonfly. These P2P systems all have some common complements, although they may have different names. Let's take in Dragonfly as an example. Manager maintains the relationship between each P2P cluster. Peer provides upload and download functions. Seed, a back-to-source download peer in the P2P cluster. Scheduler selects the optimal parent peer for the download peer. For the previous test, if we use streaming OCI plus P2P, the cluster's request for the registry will become a fuel connection from the seed, and the rest of the peers will get data through the P2P network. The 1000 pod can read one GB data in about 23 seconds. However, there is no improvement in the LLM case. It still needs more than 7 minutes. If the node and pod scale up is triggered over time, then the benefits of P2P are much higher because the node with the image cache already acts as seed. Here, all the peers don't have any image cache. Although streaming OCI avoids full image pooling, it downloads and caches partial data from the registry based on the IO request for the workload. Data will be returned directly from the local cache when the cache hits or downloaded from the remote storage when the cache is missed. Compared to the local storage or cloud disk, downloading from the remote storage has a higher latency, especially for the LLM apps, which is almost accessing the entire image. Streaming degenerates into a full loading. For sacrificial reads, overly biddy degenerates into a circle of downloading a single data chunk, wait for the cache miss, then download the next chunk. Cache hit only takes a microsecond latency, while 100ms download data from the registry if cache miss. In addition to reducing the network pressure of data source, most P2P solution can also be seen as a large caching system. We can pre-download the image data to P2P seeds in advance when the application runs overly biddy can easily get data from P2P seeds. Instance with a large disk can be used as a primary cache seed for the P2P without the need for expensive GPU instance. Pre-hitting data in P2P can also be used with OZI images, but it performs significantly worse than streaming because we have shortened the download time of image, but we cannot reduce the decompression time. With P2P system, overly biddy transform remote data accessing into the nearby data accessing, reducing the IO latency from 100ms to the ms level. It is worth mentioning that overly biddy also brings less pressure to the disk and the CPU than OZI images. Because the file module supports random processing for the compressed data, it won't bring extremely high CPU overhead like GZP decompression. At the same time, overly biddy saves the file for remote data on the disk, which results in the disk pressure being significantly reduced. The figure shows using overly biddy plus P2P to start the LLM container in a 32-node GPU cluster. Compared to the OZI image with P2P, CPU usage is reduced by 5%, and the disk BPS is reduced by nearly half. This is the summary of our test. We can only create a cluster with 32 nodes since GPUs are hard to find. The results in this table show that even without data preheating, P2P will not bring a performance loss. After data preheat, the OZI image with P2P can finish the start-up progress and mode loading within 2.5 minutes. Is there any way to make it faster? Of course. Since we know that the framework can only start after the all-model weights has been loaded, we can prefetch the required data in advance during the streaming processes. So, we have designed a prefetchor that will read specified files in Parallel, similar to use FIO random read with multiple jobs. For this LLM image, the prefetchor will create multiple threads to download the module weights as quickly as possible. As opposed to the single thread that pulls the module weights for the OZI image, leading to a faster pull. Only BD also writes certain data directly to the memory save compressed data on the disk, which also speeds up the pull times. In this way, it is much faster than a full download of an OZI image and doesn't have an additional cost of pre-downloading the OZI image on the node. There is also an advanced feature to programmatically store a trace of block reads at the start, push the trace metadata to the registry, and prefetch that data during future pull starts. Here is a demo comparing the pulled ready time. On the left side is streaming OZI with pre-heat P2P and read ahead. Pulling OZI image directly from the registry is on the right side. The test shows after using read ahead IO, the start-up time can be further reduced by half a minute. By the way, we only use one cache node in this case, which results in a limited throughput. If we have multiple nodes to form a distributed cache, overly BD can connect to different nodes during the concurrent IO request and will achieve a gigabyte level throughput. Okay, in the next part, Ganesh will introduce an experience in production of streaming OZI. Thanks, Ifan. So now we've seen how the workloads can be improved much further as well from the base case of on-demand image streaming, which is already quite powerful. So right now I want to share the experience in production in AKS to integrate the solution to show what happens behind the scenes and also to give you an example of what you can do if you were to manage your own setup for this. So the goal is that we want to have a simple user experience for users of Azure Kubernetes Service. So all they need to do is to say that they want artifact streaming or accelerated image loading to be enabled on their nodes and also for their images in ACR, they need to indicate that they would like this feature. So from the user perspective, the image conversion is transparent and so is the usage on the nodes. On the registry side, we have a conversion service that converts the image to the overlayBD image. So the regular workflow for a user is the same when they upload an OZI image or push the OZI image to the registry and the conversion happens in the background. And an important point to note is that the overlayBD image is treated as an OZI image by Kubernetes as well because it follows the spec. With leveraging the ORAS artifacts and also the reference API for continuity, on the node we check whether the image manifest has an attached overlayBD artifact as well. So if there is an attached artifact which happens on the backend on the registry side, then that image will be pulled for overlayBD and if it's not present, then the regular OZI image will be pulled to indicate that the accelerated image is not necessary. And there's also components on the node like the overlayBD driver, the snapshotter and the continuity config changes along with certain system D units that are present to make it all transparent to the users and also to monitor and make sure the components are working as expected. In this diagram you can see the flow of the different cases when the image manifest has an attached artifact for overlayBD and the way we've done this makes it also extensible to use different image formats in the future if necessary. So what are the key takeaways from this presentation? One is you can significantly speed up workload execution through on-demand image loading and this is very useful for most images but it's better even when the smaller the fraction of the image is needed at the start. So if you have a small fraction of the image needed at the start, then you'll see a huge time reduction. For large pod scale-up we can see that you can do it and improve that process through P2P either from a standalone perspective so without on-demand image loading or with on-demand image loading and that reduces your network and storage throttling significantly and the improvements are better when your scale-up is more staggered as well because nodes in your network act as peers to your new nodes. And when most of the image is needed at the start, in the case of LLM workloads or certain ML inference workloads, P2P with pre-downloading the image on few seed nodes and doing IO read ahead will speed it up even further and you'll have negligible cost increases. So the negligible cost increase is because you might have to just use one or two CPU-based seed nodes which have low latency access for your peers compared to having additional GPU nodes if you want to warm-pull from scratch. And for a simple user experience you'd want to hide the image conversion from the user. You can leverage ORAS to attach it as an artifact to your manifest and then you can use container D remote snapshotters like overlay BD on the node so that also is transparent to anyone who uses that platform. And then the user does not need to make any changes to the deployment specs and they can quickly enable streaming on their workloads. So with this we hope that you can speed up your podstarts and make sure that you can scale quickly and ensure that nobody has to wait for a while to book the Taylor Swift concert tickets. Thank you. So please leave us feedback here and we'll also have some time for questions. By the way, a couple of things. We've linked all of the resources that we've mentioned, many of the projects of all of which are open source. So you can check that out. And we'd also like to give huge credits to many people from our various teams who are involved in supporting this project. Okay. Yeah. So the question is since this talks about lazy pulling, right? So how do you ensure image integrity? How does one know that this is really pulling what I wanted and not? Like something is not switched in between. Great question. Great question. So I think you're relying firstly on the conversion service itself. So because that's completely handled by pureback and you can see the image being converted to a different format. And then you can also leverage Aura's artifacts to make sure that the content is the same. And one way for a user to verify that is they can download the same data on the node. They can actually check whether that same data is present anytime. And that ensures as well that we have the content as the same. So the other option to do in the future as well is to make it easy for users to verify it by hashing some of the additional content too. Hey, thanks for the presentation. I wanted to know how the seeding per node was set up. Like is it the open source projects you shared for setting up seeding per node? Yeah. So the seeds are for a set of nodes. So you could have one node which acts as a seed node. And there's these open source projects like the Darty P2P or Dragonfly which actually set up some of that for you automatically. So thank you. Thanks. Well, very well presented talk. I had a quick look into the spagle docs. And one thing I've wondered, I've always been sort of surprised that containerD stores your image twice on disk, right? It stores the compressed form and the uncompressed form. And sometimes there are compressed artifacts in there. It's a bit redundant. And it looks like spagle then stores it a third time, right? It stores it once inside its registry. That registry serves to containerD, which then downloads the compressed artifact from the local pull through registry and decompresses it. I was wondering if you're aware of any other of these P2P solutions that avoid that extra duplication? Yeah. So the OverLabD project itself actually has some of this optimization to avoid the decompressed format always being stored to disk. So that's related to what he was sharing about for the lower pressure for disk as well. And that's because you don't store the full decompressed format on disk as well before you read it. So that's one of the optimizations that's done in this project. Thanks. I missed that. Okay. But on the P2P side, if we sort of separate it from the streaming side, do you know if there's a P2P solution that like, for example, can serve from the same storage as containerD? So the P2P side as well, even for the... Can I just jump in? Okay. So Spiegel actually serves from containerD storage. It does. Yeah. So that's just, if you have other questions, I can probably answer those also. Awesome. Thank you. Wow. Thank you. And by the way, Spiegel's really simple to you. So great job. Awesome. Thank you so much. And we hope that you have a great trust to the weekend as well. And thanks again for coming to this talk.


I will make a plan and I will let you know.  This term is often used for such a valve. However, what we are discussing here, this is a solenoid operated but it might be other type of drive also there. Now, this lecture essentially the continuation of the lecture 15 which we delivered may be last time two weeks back. Now, first of all again let me explain what is the valve. So, we will again I shall again explain construction and operation features. Now, if I look into the sectional view of this valve this is again it is a schematic not exact section neither it is a photographic view this is may be computed develop. Now, here what we find this portion including this portion you can imagine this is an ordinary pressure relief valve. How it operates? This is connected to the system line. So, one side pump and another side may be the system. Now, the flow is coming in here not here do not make a mistake this is going to tank this portion is going to tank and this is the system line. So, here it is shown and then the flow is coming over here and through an orifice here and a construction here it is going through this passage to this place. Here is another orifice this orifice together orifice and construction together we named as A and then this is B another orifice and then we find the pilot stage. So, this orifice is D this is a variable orifice and this has great role on controlling the pressure and then after passing through this orifice the oil which is going through this this variable orifice it is going to the tank. And in between that which is not shown here there is another you can say valve block which is basically set the maximum pressure. When we call the proportionate solenoid pressure control valve or pressure relief valve in this case then this is the force on pilot stage can be given by the proportional solenoid in such a way that with the input usually voltage it might be also current input with the voltage the output that means in this case pressure will be proportionally related usually this operates in 0 to 10 volt and towards the end we would say 8 to 10 volts and towards the beginning 0 to 2 volts it may not be linear but in between from 2 to 8 volts the pressure relation will be linear. The advantage of this valve is that you can one can put easily in the control online control. So, the in fluid power usually such phenomenon this orifice flow then pressure control all such are non-linear highly non-linear but there will be non-linear inside however this is designed in such a way that input output will be linear and which can be computed directly with due to this linear relations practically no time and due to this reason these valves are used with the modern control units or sophisticated control units although performance may not be very close to the servo valves. Servo valve is having better performance considering a servo valve of equivalent size if we say that is performing with 100 percent the proportional solenoid will perform in between something 95 to 98 percent of the desired output right. Now this I have just explained explained or stated how it is performing but if we look into the performance how it works that through this orifice this passage is connected and let us consider this is closed then what is happening the oil is creating a pressure on this main spool which is supported by spring but this force is not enough to open this one so flow is being used for the system. Now suppose there is increase in pressure say I would start like this the functional feature of the valve under study can be understood from the schematic diagram and the this flow this oil is connected to here this means that as long as there is no flow pressure here and pressure here is constant as well as through this orifice C this orifice has no function with the flow main flow but this has a function with the damping of this main spool it is required when there the transient due to this orifice it dampen somewhat the motion of this and it becomes more stable if you remove this orifice C still this will work but there will be more vibration then the valve with this orifice anyway the everywhere pressure remains same so this side of the main spool total force definitely will be more than this so this will remain closed now when the pressure increases then due to the thrust it is already said we have given a force here we have given a force through the voltage there is a proportional solenoid through this end of the spool we can say here so this is giving a force in this directions so it is being closed and it it it remained closed now with the pressure here when this pressure increases the force increases then what will happen this will be compressed and the this is the main spring here this is the main spring and this spring is an auxiliary spring just to keep this is this puppet in position pilot puppet is position this has practically no function over the force whereas this spring is transferring the force from this to this you may ask why it is not direct it can be shown that if we fix this is direct then it is very difficult to get this proportional characteristics anyway so what happens this opens and once this opens the flow begins from here to here to this drain okay so there is a separate drain connection for this passage it also can be connected to the main passage over here the separate passage is function wise it is more or less same now once the flow begins then definitely there will be pressure drop through this passage now with this drop pressure here but look at this flow is through this passage not to this passage yet so whatever pressure here the same pressure will be there so but that pressure is less than this pressure so at one point this pressure force plus spring force totally will be less than whatever force is generated here so what will happen this will open and the main flow will go to the reservoir now this situation will be maintained unless this pressure is not below the whatever force we have given here whatever for what pressure we have given this input okay now the question is that we could have make it is a direct direct proportional valve is also available instead of pilot stage it is operating this one what is the advantage of this the advantage of this as I told earlier due to this pressure drops here through the different orifices this remains stable for longer period why we need such stability look at this if once the flow begins from here then here is the tank pressure tank pressure is almost 0 0 pressure or maybe a slight pressure for the filter and other things whereas here pressure is high pressure the system pressures then once the flow begins then definitely there will be pressure drop as well as here will be also pressure drop by using so many orifices what happens that here the orifice opening is very much controlled so that maintaining the pressure almost equal to the system pressure the flow the whole flow is diverted to the tank this is a large orifice as you can this is also a variable orifice but this is a large orifice okay so this is basically the operations now I have shown you that by the equations how the pressure is being dropped what the force everything a part of that today I shall discuss the rest of the portions now here again if you look into this this here there is a closed loop feedback here we and we are having a LVDT that is that controls the armature positions for an input this is not closed loop for the whole system this is closed loop only for the proportional solenoid which is displacement of this solenoid is recorded by LVDT and through this it maintains the position with force to generate a particular force in this directions okay now this hydraulic parts the advantage of proportional solenoid valve is that this other hydraulic parts including this one this is the maximum pressure set again I would say suppose this is working say at 10 voltage let us consider maximum pressure can be control is 10 MPa or say at 8 voltage because 8 to 10 that may not be linear at 8 volt say 10 MPa or let us consider 8 MPa then this valve here the setting will be slightly higher than that so that if pressure increases above that then this portion will not work this directly it the flow will continue like this which including this an ordinary valve this is an ordinary valve so this is additional safety feature however this valve can work without this one also until there is say something wrong with the voltage input or otherwise it would work suppose if the pressure increases up to 12 voltage still this will generate only the force for 10 MPa and this flow will be there but with this there will be no chance of damage at this portions so that is why this portion is additionally introduced there now so orifice A and B are considered as the two resistance placed in series in order to achieve the required optimum pressure drop before the pilot stage if we replace we have done of our own experiments and we have seen if we replace one then performance is no longer linear neither the stability is available there so this as these are designed in considering the linearity as well as proper function now what we did that instead of that block there we put another block just manifold you can say so with the whole passage hole and keeping the passage hole intact but this facilitated us to put the connect this one pressure gauge here to measure the pressure here another pressure gauge here to measure the pressure here another pressure gauge or transducer to measure the pressure here and another to measure the pressure here and another one to measure the pressure inside this pilot stage however we did not have much scope of measuring the pressure at these two points very closely what we consider whatever pressure is there the same pressure is here as well as whatever pressure we are measuring here the same pressure is inside that roughly why roughly it is almost giving the pressure drop within this variable orifice may be slight error is there but it was very close to that so our arrangement was like this two major pressure at different points now the primary objective of the analysis is to predict the set pressure supply pressure so what we wanted to do we wanted to study the steady state characteristics so for the steady state characteristics if I know if we know the proportional soil solenoid feature fully completely then from there if we know the orifice area everything can be calculated and we can develop the design procedure of such a valve however it was very difficult to know the real solenoid characteristics neither it was possible to test it separately because it was it was a integral part so what we did by some trial error error we first found out what might be the force what are the forces generated by the armature solenoid armature at different voltage for that what we could do we measured the different orifice area we could measure the spring stiffness we could measure the dimension of the puppets dimension of the solenoids angle etc. this data is available with the manufacturer but the problem is that they will not provide us the data so we took one valve and we measured all such parameters and then we tried to establish the design procedures particularly to examine the steady state performance and also we examined if we change the orifice what orifice dimensions then what will be the changes in the performance in the valve and for a given input voltage to the proportional solenoid the flow rate through the pilot stage that measurement we did so what we did while the oil in between these passages we put a flow meter like this just to measure the flow through the pilot stage all the intermediate pressures along with the pilot stage was measured by placing the transducer at different places at steady state conditions same amount of hydraulic fluid that enters through orifice aid will pass through orifice so using the orifice equations we can write down the equations because we know the pressure at different positions so we can write down the equations of for the flow and we can easily knowing the flow rate we can easily calculate the how much drop at different places even say for that per pass if we know the dimension of the orifices even we can calculate what is the coefficient of discharge at different points now the flow equations that means we are now considering the flow from here to this to this to this path and here so first of all first we consider the flow through this path q d we have measured and then we can write down this equations this is root under the pressure difference here this pressure we have measured not here we have measured the pressure here because the dimension of this rest constriction could not be measured however there should a row term this row term is included with this term what we have considered ca is a coefficient not coefficient of discharge this as I told including this row figure this is a coefficient this coefficient is for this orifice and this coefficient is for this orifice these two restriction say like a spring resistance in a series so as you know for that purpose we can write down the equation in this way so we develop these equations but this flow again equal to flow through bridge so we can write down this equation the c b also includes that row value I will show that how it is included then through the orifice d we can this is the variable orifice this equation definitely will be different where y p is the displacement of this puppet ok c p is the again the coefficient of discharge and row part and p c p d is the pressure difference between these two points so we have written in this term but this can be detailed analysis considering the area etcetera I will show that area is also there included now flow through e also we can write like this now here I would like to mention that orifice a and b like the if we say this orifice normally we think this is a very thin plate plate sort of things through which there is a hole now orifice may be a straight hole or orifice usually may be in the convergent towards the downstream what we saw these are these two are of that type this is convergent in the downstream and this diameter is very small 0.5 or less however this orifice was slightly longer this e is a small hole diameter is more or less same a slightly higher than this but this was a long one but as we know that for such a small orifice and such a long orifice knowing the diameter of the hole and length ratio we can use different formula like this however here still this formula can be used if we can properly evaluate that c c e now in all this above equations this four equations I have shown c a c b and c e for the three fixed orifices a b and e respectively these are defined in a general form as c i is equal to c d i a i root over 2 by rho. So, this coefficient includes the coefficient of discharge area of the orifice this is the nominal area I would say nominal area in a say we directly we can write this a i is equal to the pi d square pi 4 where d is the diameter of the hole without considering its q of h. Now, i is a b e etcetera for respective orifices now c d i can be evaluated from the earlier equations 4 16 2 if you remember the earlier equations I think it will be 4 15 not 16 the earlier lecture. So, this is 1 by c d square is is equal to 64 l by d where l is the length of the orifice d is the diameter of the hole and r e the Reynolds number plus k as a constant. So, l by d ratio the orifice varies from 1.5 to 10 normally in this case these are these two orifices was very close to that whereas, this was slightly higher, but not 10 exact dimensions I have not shown here k is a constant which can be evaluated from the above equations knowing the value of c d from experiments if we find out we can find out the c d then this value also can be found out and then for a particular type of orifice perhaps we can develop a and empirical relations. So, that we can calculate k any time the coefficient c con for the constriction here after orifice a is expressed as with this relations we put the constriction area here and 1 by k loss we measure simply the loss there and from which we can find out this coefficient. So, as we know the pressure drop at different point to measure the loss over here what we did we removed this one and also we removed the orifice simply we measure the flow and pressure drop at this two points and then we found out what will be the loss there. Now, from equation 21 the drain pressure p d can be readily evaluated in the written line and pressure p r is also known this pressure also measure. So, this is known. So, with such the known values we can calculate the initially what we did we evaluated all coefficient of discharge whenever a orifice is put we first evaluated the coefficient of discharge of all such points. Now, this p r is not very high it is 0.5 to 08 mega Pascal only that of course depends on how much restriction you have put in the written line if there is one filter only then may be one value if filter with say cooler is there then it will be more this depends on the resistance which easily can be measured. For the relation of the p c p a and p a s from equation 21 the pilot property displacement has to be determined first. Now, you see this first we have measured the pressure and next we have found out the c d and from which we have prepared the set of equations. Now, what can be done with those using those equations again we can p c p a p s all we can p s is known value all we can calculate with respect to this displacement y p displacement. Say for example, this means that next for the next calculation we need to calculate the y p how much will be the displacement ultimately we have to put in terms of the displacement all the equations. So, in order to find y p that is the pilot puppets pull displacement p c and p d is replaced by the pilot stage force balance equations. So, this equation 14 if you remember this 14 equation was used in terms of q d and y p obtained from the equation 21. So, first we calculated c d and etcetera then we from knowing the q d we calculated y p I will show this equations. Now, we should recall here what is the geometry for this puppets pull or the orifice area if you remember in the earlier lecture I described that how the flow is occurring here the flow is coming over here and then this flow is going like this and it is ultimately going into the tank through this orifice e and leakage passage. Now, the we know this angle we know this whole diameter. So, area must be this annular passage that which we can calculate from this I mean it is not like that that we are subtracting this area from this area rather we are considering the perpendicular path through which the leakage is going.  So, we use this equation to estimate the area. Now, here another point is there what is the z angle here in normal course we can expect z angle will be pi p, but in real case it is slightly higher than that. That means there is a separation of the flow here. So, flow you can say that it might be slightly higher than this. So, actually we should take that angle here, but there is no way we can measure this angle. So, what we do we take this angle later we put a correction factor knowing experimentally what is the flow actually occurring there. Then with further derivation equation 14 is transformed into a third order polynomial equation for y p and is expressed as I am not showing the details of this equations from the note you can or if you just go back to the earlier lecture from there you can calculate and ultimately we can put this equation in this form. This is the third order polynomial equations where a can be put k s p and c p and b is put within these terms these are coefficients these are all coefficients where this is the force driving force and c is c v p then eta q d 3 by 2 2 pi d p by rho sin 2 theta p. So, these derivations again I am not showing here these derivations can be obtained once we exercise these equations then automatically this terms will come and which are put in this form and d is equal to minus a p into q d a p is the area of this I mean this whole not this or if we share a p is the this whole diameter which is a known factor q d is also known. Now as in equation y p equation 24 clearly there will be three roots one of that will be positive and real and which can be considered as pilot puppet displacement. So, if you solve these equations then we will have three values one of that which is positive and real we will consider that value for the puppet displacement. So, combining equation 21 to 24 the different pressure are finally expressed as this p c the pressure here is equal to p b that means p c and p b this zone pressure is derived by q d is the drain flow divided by c p y p square plus p d then c p we have evaluated earlier y p we are calculating from these equations solutions and then clearly we can calculate the pressure there and p a is q d by c b square plus p b and p s is q d square by 1 by c square plus 1 by c con square plus p a this all the equations written from the earlier we will have the equation we wrote the equations and the this just we have written this equation in terms of pressure. So, this easily can be evaluated and after that the variation of all the forces involved in the force baron equations with the common voltage for the pilot stage illustrated here which we can derive this force equations earlier we have shown equation 14 this earlier lecture we have shown now here we have plotted now if you look into this figure now here system flow is this much q s that is that was the system flow and for that f d r f this is f d r these are different forces f d r is the force form for solenoid f s p is the spring force f f p s is the flow force am I clear f d r is the force generated by the armature I mean that solenoid proportional solenoid f s p is the main spring force not this one there is a spring this side this is not the main spring main spring is here.  So, these are plotted so this will be the nature of the forces here now individual forces are evaluated analytically from their respective equations this which we have done earlier it is observed that throughout the entire operating range the pressure force f p r p largely follows the driving force f d r this is the driving force the spring force remains nearly constant in between the spring force after some initial increment. So, this means that at the say for example, when the valve is being operated may be the voltage input 4 to 7 or 8 rather here the linear portion is 2 to 8 for this valve. So, for voltage input from 2 to 8 what you will find this spring almost acting as a solid bar and the armature force is being generated by the balanced by the pressure force and flow force again I will repeat that why we need that spring if we give that force directly by this pole there will be nonlinearity this nonlinearity will be reduced if we use a spring in between that the flow force is found to be increasing with the increase in common voltage. Obviously, if the force is increased then what will happen there is a much pressure drop with much pressure drop there is the increase in flow rate. So, there will be increase in the flow force. However, the magnitude of flow force is negligible in comparison with the other forces this is again that although this force is increasing flow force, but still it is less than the other forces unlike the pilot stage in the main stage the flow force has a significant role on the steady state force balance of the puppet. Now, here what we are showing this is the main puppet we are showing if you recall the valve configurations this is the main flow through which the main flow is going to drain in case of relief. So, in this case the flow force has significant role the main reason is that quantity of flow is much much higher here and definitely as I told for the balance for the longer stability this valve is designed this means that this orifice area is very small. So, that there is enough pressure drop to maintain the system pressure close to the system say in case of direct valve what happens once this puppet opens the pressure drops inside then again it close and again it opens. So, there will be chattering sound, but in case of this balanced piston I am pilot operative valve what is called two stage valve this remains balance for longer time. So, that is why there will be the less orifice area much flow and due to that here will be the high flow forces. Now, here the flow force for different input conditions are evaluated using the expression 12 here the equation 12 I am not showing you should compare with the earlier lecture and this is according to the equations 12 whereas the from the equations the other equations there is equation 18 we get a different value one is one the equations we developed from the general equations another with respect to the valve in terms of force and other things. So, why this difference is there definitely as I told we could not consider all the parameter inside. So, there will be some differences now these differences are observed in all cases who have analyzed such valve and therefore, we need to rehabilitate the equations considering a factor for these corrections which we called correction factors. So, the flow forces obtained from two approaches are clearly illustrated in the both the figures earlier figures and this figures also and then the inequality essentially demands for a correction factor which should be introduced in the expression of flow force. Now, we will look for that one now the modified equations of flow force is then can be written as with a factor we have these equations again we have rewritten and here we have earlier we developed these equations without this one. If you remember this equation we developed earlier where we did not have this one. Now, we have to calculate this one this kappa this factor this is the correction factor. Now, where k the correction factor k or kappa whatever we call it I think we used kappa the correction factor is the ratio of flow force obtained from equation 18 to the ideal flow force given by equation 12. 12 gives the ideal flow and 18 gives the obtained flow from these geometries and other things that means, 18 equation without this kappa was there. Now, in some previous investigations this in the reference earlier reference we have given today I also give the references this say Davies it is 1994 this is 1998 this is even 2002. They faced similar problem and we also we carried out such analysis in the year of 2004 yeah 2004 and this time we when we had to face this problem we found they also faced similar problem, but their valve was different. So, we had to evaluate this value of our own as shown in figure 8 the factor k is not constant, but is found to be varying with the supply pressure this is not the figure 8 the earlier figure 8 this kappa value is not constant in found to be found to be varying with supply pressure. So, measuring the supply pressure we can find out this values. Now, to find out this what first of all we should know what is the angle this poppet angle here. So, knowing this poppet angle due to the typical poppet configuration the flow angle may not be same as the half poppet angle for all the input conditions I mean here again this we wanted to mean that z angle is not always matching with the phi s. So, due to that this correction factor is required the actual flow angle seems to be larger than this geometric angle of the poppet large flow angle enhance the flow force the assumption of uniform pressure distribution on the external poppet surface may not be applicable here the characteristics of the flow force correction factor may be used as a reference for the sensitivity analysis of the valve. So, this not only this correction factor from the correction factor again we can examine the sensitivity of the valve what is sensitivity that changing the parameter like a spring constant and other value what will be the change in the flow or pressure etcetera. An attempt has been made to calculate the armature displacement. So, if we think in terms of design of such valve. So, now we need to consider what is the armature displacement without the details of the constructional and functional features of the solenoid the displacement is predicted from the geometric details of the pile of threads and the developed driving force model you see as I told that it was very difficult to measure the displacement of course if we can calibrate if you could calibrate the LVDT and if you could the take the output from LVDT then it could be possible to measure the displacement, but whatever the information we already have we have the geometric relation inside we have the spring stiffness we have the flow and from there we can find out what will be the displacement and from that equations definitely it is possible to find out the armature displacement and what we established and with that armature displacement we again reexamine for different pressure setting and we found that result was correct. So, we consider that is the armature displacement and ultimately we developed all the equation in terms of armature displacement also. Now, here this first of all to do that what we measured that we measured this length so this is a fixed geometric length and then say this is the say this point is touching over here when it is 0 positions. So, what we measured the LP we measured from the top to this positions that means if we measure this distance that is LP was when LP was 0. Now, this is you can say this is the opening from the orifice point and then this is the position of this seat I mean this step and here also this step these two are some fixed dimensions and then this is the dimension for the compressed spring which we the free length F LP is the free length of the spring minus this displacement and here again we had to measure this this cap dimensions because the spring was sitting from here to here only. So, this dimension we had to include and then by equating we were calculating the displacement of the armature. So, here the critical values are these because what is the compressed length of the spring and to find out this armature length and we had to consider this length also. So, these are all fixed length geometric so this will not vary, but once with the force this will vary this will vary and this will vary. Now, next the equation the armature displacement can be written in this form I am not going into the details knowing these dimensions you can easily find out say this is the L I O this is the LP. Now, it is not exactly matching this I mean because this is written in may be one format this is other format, but these are corresponds to this. So, L C is here these dimensions L L is this one L B is this one. So, you will be able to understand why this figure is enlarge I think you cannot read it, but there is slightly mismatch anyway this is this dimension which can be estimated this is the fixed this is also fixed dimensions this L C is also fixed dimensions this is also we have to measure. Now, where the poppet displacement y p and the pilot main spring compression y h s p this one y p is evaluated from the analytical model we have already developed. Now, the driving force is transmitted to the poppet through the pilot main spring therefore, y h s p is found from the equation of the spring written as y h s p f d r this is the driving force of the armature divided by k h p is a we can say this spring constant of the main spring. Now, this is again you can see are evaluated all three displacement involved this armature this and this in the pilot stage are plotted against the current. So, if we have now plotted these three characteristics now this one is the y h s p that is the spring compressed spring length. So, this displacement of the spring and y p is the displacement of the main spool and y armature is the displacement of the armature. Now, if we look into study this curve this is as you can see this linear and this is also we are getting linear whereas, this y p is not linear with the displacement and current. Obviously, when current is less then displacement will be much higher this is obvious you see this current is less means the load is less and that load definitely this less pressure drop. So, there will be more displacement it can be seen that the armature displacement becomes linear after some initial non-linear region at smaller current range suggesting presence of inherent non-linearity within this valve. You can say this this is in terms of current we have written because ultimately in the armature what is fed that is the current our input is voltage that converted into current and that current relations we find non-linearities here as well as there will be some non-linearities here also. So, from this to this you can say linear and this is we normally keep the operating zone from this to this that means about when the current is 0.7 to 1.6 it corresponds to roughly 2 voltage to 8 volts. So, now as you see this from this point of view we need to modify this our equations for in the usual form and what we find considering that the armature position for different input currents for different driving force that is for the different driving force is independent of pilot means spring stiffness. So, definitely we can examine if we change the spring stress spring stiffness what will happen of definitely the range of voltage might be it will change, but performance may not change very much as I told after an initial compression the spring almost act as a solid var. Consequently the pilot for a proper displacement may be expressed in terms of driving force pilot the main spring stiffness and the armature displacement. So, modifying equation 27 now the expression we can write in this form here directly we have the spring stiffness which we have measured and the force also we can estimate from our input voltage and others and we can calculate. So, with this we have this part we have replaced this one we have replaced by this force. So, now y p can be calculated and in the analysis the pilot flow rate is no longer an input it is not an input our input is the voltage we can say it is an unknown quantity and is to be determined from the analysis say. In fact, y p now we have to estimate for the estimate the performance the pressure drop across the pilot stage is to be evaluated before the evolution of the pilot flow rate from the force balance equations for the pilot stage. The pressure drop may be evaluated as now we can write down these equations this a p is this or if this area a f s is this ring area and we can calculate p c minus p d knowing these two force. So, now we have to finish very quickly. So, I would like to say the from the pilot stage force characteristics the pilot stage flow force is found to be negligibly small in comparison to the other forces. Instead of using equation 3 for the flow force it is quite reasonable to express it in terms of pilot puppet displacement and pressure drop assuming constant coefficient c d p and c v p the final form of the above equation now written in this form whereas, the c d p and c v p is the two coefficient of discharge at this points. So, these are separately evaluated and we can now write down these equations. Once the pilot puppet displacement and the pressure drop are evaluated pilot flow rate can be found directly from equation 14. The individual pressure are then evaluated using the equation 21 to 25 and here we have seen the three different plot. The analytical results what we have done actually we have estimated what will be the sensitivity the analytical results is plus minus 5 percent change in the pilot spring stiffness. This is purely theoretical analysis what we have developed with that why we have shown here you can see the change in pressure and this common voltage. This is 100 percent means the original spring and if we increase this stiffness by 5 percent then it is this one and if we reduce the stiffness by this one we will get this is the curve. This means that by simply changing this spring we will have different pressure range for different voltage, but the nature of curve is more or less same. Let us examine the other also that what will be the changes in q d what we find here for the our original spring this is more or less constant linear whereas, due to these two changes what we find it is becoming highly non-linear. So, and also if we look into the flow force correction factor we find that these two are also different from the linearity and then obviously if we want to use say for example this is 5 percent less we have to very careful probably this design will not be feasible whereas, by increasing the spring stiffness the 5 percent we can still use this. So, this is with this I would say that I wanted to show that how a proportional valve can be analyzed for its steady state performance. We have not yet shown what is the transient performance. Now I think you can understand this from the self study and there is of course the conclusion part which I am not going in details because you have to read it, but I have discussed throughout this presentations what might be the conclusions and finally these are the we these are the main source from where we have developed I have developed this lectures including our own research and thank you for listening.


Can you end your contract after 3 years and come back as a freelancer? Yes, you can come back as a freelancer, it's no problem. A freelancer visa, it's your wish you can come back. Yes, what about the steps for you to come back after completing your contract of 3 years with the sponsorship under the company and you wish to come back under the freelancer? What are you supposed to know? What do you need to know as a parcel? What do you need to prepare yourself? In this video, I'm going to let you know and share with you what definitely you expect and what definitely you should prepare with and what definitely you need to know. By the way, if it's a first time coming across the channel, don't forget to subscribe. It's from the next creation TV, from I am next giving all updates. My TikTok account is next creation at I am next giving you all the updates. Yes, let's talk about ending the contract. Ending a contract under what we call the work sponsorship. Yes, most of us we've gotten into a scenario that we don't wish to work for the companies anymore. We don't wish to work under the conditions of someone anymore. We want to be ourselves. We want to have our own housing. We have to have our own freedom. We want to have space away from the direction or directive or under the custom of someone's accommodation. That is under what we call the work sponsorship. So this is when you plan and say okay fine.  What you call a freelancer visa? Also something that you need to know about a freelancer visa. It's really not a free visa. It is in the custody of one of the nationals who is called a sponsor. But that sponsor that's not employing, does not give you transportation, does not give you food, does not give you accommodation. He only gives you what you call his visa to be used in his name or his company. You are under that company but that company does not employ you. It tells you go and look for your own work.  What his role as the visa owner is only to renew your residence permit because you cannot renew your residence permit by yourself. What you call the QID. So he has to renew your ID, what we call end of every end of the year. You want to take the medicals, he will be on those papers. So you call a freelancer. So when you want to come back as a freelancer, it's okay. You can come back as a freelancer, you have the right. But in this situation, look at very many things before you think about that. Yes, you want to come back as a freelancer. Because remember when you want to come back, you will first have to exit the country. To the nearest entry, then you can make re-entry. So if you've been under sponsorship of what you call a security company and you want to come back as a freelancer visa, what you need to do. This visa will first resign and exit the country. Then come back on your visa, which is a freelancer visa. And that freelancer visa, you will come back into the country. It will be processed into the country.  Then he will tell you, now go, start looking for your own work. But remember you are under my sponsorship, under no supervision at all. So what happens most of the times? When you want to come back this visa, which must be got from companies that are giving out visas. Yes, it is, who is that person to be trusted? That is the question that you need to ask yourself and you need to know. Yes, if you have that person that you think that company you trust that when you exit, they will give you the visa to come back. Yes, well and good. You, you pay for it. Then you come back in the country. You start the struggle to look for job, to look for accommodation. If you have money saved aside, it's well and good. You can start up for yourself. It's okay. But where the problem comes from is that most of the times we do not have the trusted people. Even those companies that we tend to trust, they do not give us exactly 100% or even 50% of what we need. So we end up getting in two tiers and having what we call regrets. The other disadvantage part of it all that we have what we call freelancer visa is that a company or what we call a company may give you this visa but the company has a lot of problems. The company will give you a freelancer visa for two months. After two months, you find the company is closing down. So you are left into the space like this. We don't have anywhere to run to. It's only that company where you have the visa will have to give you an NOC to go to another company for change.  You need to be strong and you need to be one person that can accept that if this comes I have an option or have part B that I can deal with this one over the other. Then you need to know that under the freelancer you are on your own. You will take care of your feeding by yourself. You will take care of your accommodation by yourself. All those are expenses but if you are prepared well enough for you to take care of those expenses there is no problem you can start up. You will have to look up a job of your own at that time. Remember all those ones are in bond by you the person who has a visa. You have to look for the job that is going to give you the amount of money or salary that is going to be paying your rent or is going to be paying you your transportation and will be taking care of the accommodation or what even what you call the medicals. So the person will ask me ending your contract and coming back as a freelancer visa it's okay you'll have freedom but there's a lot of things that you'll be born by you or there's a lot of things that you'll definitely you'll be paying as a person unless unless you are sure that you are going to get a very good job that has that money that will be able to cater after to cater to cater for you or to cater for your life otherwise that will be the only way that I can let you understand it in that kind of situation. Hope I've tried to share something for you. Thank you so much for supporting remember it's next on the next question giving you all the updates and giving everything that you need to know.


The presidency has blasted the Amnesty International for allegedly supporting the indigenous people of Biafra, IPOP, which it accused of stockpiling substantial weapons and bombs across the country. This was contained in a statement issued by Garbashihu, senior special assistant to the president, media and publicity, in response to what it called Amnesty International's later salvo at Nigeria. The statement said while the global rights group did not say anything new, it has decided to side with terrorists. The statement read in part, again, they have decided to side with terrorists before the liberty of those they injure, displace and murder.


Okay, so I'm Willow. This is Tamate. We're going to talk to you today about things being on fire. We all get to play with a lot of awesome things all the time, but because technology has become ubiquitous, we get to deal with it in disaster, in revolution, and in crisis now. And it provides some really interesting problems. So this talk is your disaster slash crisis slash revolution just got pwned. And these are your introductions. For people who are following on the Ustream, or not Ustream, what are we even, I don't know, following the stream or what have you, you can follow the presentation at Bitly Telecomics Guab, and you can also go there afterward and kind of go through. There's more information embedded in this than we're actually going to cover right now, and we'll keep updating it as more things come in. So a traditional response. Will you hit the button for me? I will hit the button for you. Yes. Okay, so traditional response in humanitarian stuff is super top down. It's modular, but it's closed source because there's a lot, it takes a lot of money to get a satellite up into the air in order to make imagery. It takes a lot of money to deploy people. It takes a lot of people to train people. And so it ends up being closed source and very hierarchical. It's not very distributed. But it just works. Just that thing. Okay, next one. But because it just works, it seems sometimes like you're parachuting in. It's white dude in cape, right? You show up and you're like, I'm here to save everything. Because you're saying what people need, how they're going to receive it, et cetera. But it also means that they've figured out some of the problems of how they work together and what not. Yeah, as we all know, there are hacktivists outside parachuting in at the moment in different crises and revolutions and anything. And an advantage of them is that they have opening lines of communication. They're open to the people who want to help. I don't know who I've ever tried to help with the Red Cross, for example. It's very hard to get in. It is a closed system. And it's much more easy to work in activist groups, well, at least not telecomics, but others. And this is one of the big advantages. Everybody can fallow and they have different tools and different risks with these tools. So when telecomics is offering a tool to people in Syria, for example, we tell them about the risks, what might happen. It might happen that you get tracked down, full stop. We tell the people we transparent with the risks. It is very important to be transparent on risks. And the closed system, the old groups are mostly not. They just there and popped and then they go. We try to leave at least a contact where they can contact us that people get informed what is happening afterwards. After they use our tools, for example. Is it still working? Is it still secure, for example? Yeah. So it's, oh, that did not work the way I wanted it to. Maybe? There we go. Okay. So because you are offering up new tools for people to use, there are things that we don't understand about them yet. So there are people who have done some of this wrong, so I have to look at it to remember where I'm at in the presentation. So crisis mapping is where someone who's on the ground can text in or they can tweet or they can post to Facebook or they can do whatever they like. And that information is pulled into a database and then it is parsed by volunteers to be translated, categorized, geolocated and verified. And then that populates a map that first responders can use to figure out, well, what roads are closed? Who's trapped where? Where is their food? Is there a generator somewhere? Things like this. And that's awesome except that you need to understand who is using the map. Do people who shouldn't have access to that have access to it? If you're talking about children being lost in a basement or you found some kids in a basement, you don't just want to tell everyone. That's a very bad idea. And most people who do crisis response think everyone is altruistic as they are and unfortunately it's not the case. And also if no one is using the map, then you've just provided a false sense of response to the person who's texted in. And then maybe no one comes, maybe you've just made a map and then who cares? There's also the idea of crowdsourced volunteers. There's this huge deluge of information that happens because everyone's super excited to have a voice in disaster crisis revolution, what have you. But who's using that? Who has access to your data set? It's very important if you have volunteers in your group that you build a web of trust. So there are people just jumping in, for example, and I see them say, hey, I'd like to help. And I say, well, great, but who are you? Why? So what are your motives to help? Why do you choose our group to help?  This is a very important question, the question to ask, who are you? Yes, groups need to be open, transparent, but in case of a crisis, there's a revolution. There are groups working. It is most times not possible to directly jump in while the group is working. This needs to be known that this just doesn't work. Groups need to find something else and to form. And it is very important that you don't give access to everyone just jumping in. We had a great example of bad software. It's archetype. There was a software, we got a mail of telecomics from the Fluid Nexus crew. They said, hey, we have a great software for activists. You should promote it for us. Because you were inspiring us and I was like, wait, the mail was reading like a cat and log. And we did not do anything without. Then there was a little hacker crew who thought, okay, let's have a look at this tool. And they needed about 12 hours to destroy it completely. It was destroyed. And then they wrote a paper about it and sent it to them. Hey, guys, please have a look at these bugs. Well, the whole tool was a bug. And then they went, instead of saying thanks for pointing out these bugs, they were arguing. They said, no, it's secure. Everything is fine. And the crew said, no, it's not. As proved here in this paper, at the end, someone had to left the Fluid Nexus crew. And it's still not back online. The software, well, there's a beta, but it says, do not use in the field on the web page now. Before it said, hey, use us in the field. It would be a great software. So when you're doing software for crisis response, please do it open source. Give it to hackers.  Let them break again and repair again until it's really done. It is. So as we hear on Hacker Congress, I know many hackers are here. Please be nice to those people whose software you have broken. It's way better to be broken by your friends than it is to be broken by people who don't care. Yeah.   And when you do software and someone breaks it, do not complain about that it's broken. Make sure that it's unbroken sometimes. Thanks. So your goals are that it's secure, then that it's open, and then that it's easy to use. If it's not easy, people aren't going to use it. Especially when things are on fire, the last thing you want to do is check the language. And if you dropped a semi colon, you don't want to do that. And so make friends with designers. They have silly hats, but they'll help it work. A lot of us working in a. At least no one on the ground likes to open up a terminal. No one likes this. They want just to click. And then it should work. So if there's if you have configuration for your tool, don't make an expert mode. People consider themselves as experts. Every time. And most expert modes, we can mess everything up. Don't do expert modes. Please ask the designer how the your eyes should be, how to be a workflow. What could you do that people feel comfortable with the tool? So don't throw an error with just null. Please explain the error to the people using it. It is very important because if I don't understand a tool, I will not use it anymore. It could be as great as possible. If I don't understand it, I don't trust it. I don't use it. And that would be bad. So make friends and accept the challenge. Okay. If you deploy in crisis, it's too late. People need to be using the things that you make already in their everyday life. The reason Twitter did so well and had so much impact during the Arab Spring is because people used it every day already. It was a part of their lives. And so what people already have, what they get is what they use.  It's the best time to request new data sets. It's the best time to push new initiatives through governments. The other team does this, so I feel pretty okay about being manipulative like this. Best example at the moment in the Arab Spring, people use Skype. Because it works. They install it. It gets through the firewall. They don't need to configure anything. It just works. Skype finds a way out of the computer. And unfortunately, back in too. We all know that. So it's not one way. We always say to them, don't use it, but we don't have anything else. So if we don't want the people to use Skype anymore, we need to build it. And we need to make it easy as Skype. So things are still on fire. So these are real people and it's real problems. These problems are universal. They're complicated and they're fascinating. So they're the best puzzles ever.   But no pressure, still try. And do all the tests. And wear pony shirts. So yeah, we do serious business outside. But we all should take breaks and dance a little bit. Dancey, dancey, dance. Yeah, it's important to have fun. This sort of work wears on you. I like to think of the things that I build as the zombie apocalypse tools and the things that I interact with. Because if you talk to people about lost children and things being on fire and we can't find your parents and your church collapsed or whatever, people get really depressed really quickly. Who knew? So having a sense of humor about this not only helps you keep your sanity, but it also helps you communicate to the people that you need to interact with. Yeah, take care of your Hacker friends. It's very important. Take care of them. If they are only working all the time, force them to go out. Just break into the apartment, kick the door, raise all the shoulder and wear them out. They need to get this. If they don't eat anymore, bring them food, cook for them, cook together with them. There's so much we can do for ourselves. We can take care for each other. I mean, we are not machines. Well, you are, but we are no machines.  And so please take care of your Hacker friends that they not die anymore.  Well, maybe two sentences of we're recreating ourselves through our technology. We can only create tools that are within our experience to create. We only address the problems that we see. And so any issues that we run into with what we build are really human problems. The issue is not necessarily the security of the code. It's that people will manipulate or use the security holes in the code. And so if you make a tool that gets out of the way of the people using it, you let them trust the people that they would choose to trust. Does this make sense? I don't know if I'm explaining it well. A little bit. Okay. Just a sec. Let me let me do a thinking dance. I have to move in order to think. Okay. Interpretive dance. That's my name. Interpretive dance pony. I'll get it. Interpretive dance cutie mark. What could possibly go wrong? Sorry, okay. So people will have a good gut instinct about who they should trust anyway. And so if you're creating secure networks where people have the choice of trusting the folk that they would anyway, then you've made a good tool. If that is intercepted in some way, then you haven't. But the issue is not necessarily the technology itself. It's how people use it. I think we all know. But it's good to say every once in a while. Tell me if I didn't make that clear. So, eh. Okay, let's move on. All right. Cool. Okay. I'm going to move on. I'm going to move on. Okay. The whole concept of open data and transparency on processes and how we work is in fact, political. So parachuting in like the Red Cross is a political act. And there are other hackers who say shut up and hack. So they see themselves not as political. And this is okay. Most people of ours are political in a way. And some really just say technology is neutral. And I don't care who's using it. But you can really, really work together. It's not exclusively that if someone's only hacker and doesn't want to use it in a particular way, that it can be used in a political way and the other way around, of course. We want to have this discussed later on. But we'll do that later. Yeah. You can get involved comma bitches. We mean that. We are in the last months, we have seen, oh, there are people working. And it's great. But no, I sit at home and don't do it. Anybody can do it. Form your own groups. Help people get things done. Help people on the streets. Help people locally. Help to solve their technical problems. And get involved. I mean, it's very easy. Do one thing well, then evolve to more things. And people will get your name. They will listen up if you say something. And they will ask you for help. So you did one thing well, then do well again. And again, and again, and again. You cannot expect that people on the ground will just trust you because you're there. Telecom is now gets contacted by people on the ground. When we started earlier this year, we need to contact them. So this all can change in the group. And if you have done well again, you can eat cake. But not before. So document and communicate. If you don't, if you don't document, no one cares. They're not going to be able to care. And if you don't communicate, no one will know. Again, obvious, but still needs to be stated. Also test and play. There's something coming up called, well, let's go in order. No, okay. Can't Roberts is happening, which is United States based, basically non non government organizations, nonprofits, military, private sector, etc. I'll get together and they run through a scenario. They actually have people out in the field running around trying to complete missions. It's like, find this thing. And it's an adult scavenger hunt. And it's awesome. And they see how all their tools are interacting and what people can learn from each other and what the next steps are of integration and etc. But this time, they've learned that there's a term called red teaming. There's progress. And so if you want to participate remotely and either attack or defend, those are the dates get in touch with me. And it will be super happy fun times. Yeah, on the other hand, they're, for example, random hacks of kindness. I'm sure you heard about that. This is great. People on the ground say what they need. And this will be done. It's twice a year, where people gather and I think 27 cities all over the world.  And then it's documented. It's released and people on the ground know that they can trust these tools because they requested these tools. It is really nice to help. And random hacks of kindness is a very good point to start to see what is needed on the ground. How can I contribute to that? And yeah, so get informed about that. It's very, very great and important to help there. And then there's the break fast. And random hacks is only two days long. So it's a minimal commitment. If you want to kind of go get your toes wet. Break fast. So in the spirit of breaking something before eating breakfast, but drinking a lot of latte in the meantime. Next weekend. So that's day the seventh, I think we're going to be at sea base and in the spirit of breaking things. So come and do an exploit and then we will feed you. Yeah, I guess that's it. So again, with the with the Internet's in the follow up and we'll do that thing. Yeah, so when you do something, when you contribute, or whatever, stay open. It is common. Meanwhile, the hackers seen that we do not talk about what we have done on great things. But it is important. Because if you tell that you're doing great things and help people, others may see, hey, I can do that too. And other people who need help will see, hey, these guys can do this or these guys can do this. So stay open. Stay open for other hackers. Stay open for for people who are in need and stay open for the problems. This is important. Stay open for the problems. Don't make the solution for a problem which isn't, which doesn't exist. We very often do this.   Telecomics is doing this via IRC. They coordinate themselves. There are many links out the side in the wild where you can find how we're working. You can try to get into telecomics, which is unfortunately not that easy. Well, we try hard. But it's not that easy. On the other hand, you may take the design pattern and make your own group, which is like telecomics with even a cooler name, maybe. What do you guys do? If anyone here doesn't know what you do, what does telecomics do? Yeah, what do we do? We started as a political body and evolved to an activist group. Now we do merchandise with activists together. You can buy shirts. In the Arab Spring, it started for us with Egypt and we provided modern landlines to the options when the net was shut down by Mubarak. Now, in Syria, we released lockfights of the blue coat routers to show the world what is happening there. We help people to circumvent surveillance and censorship. So and these are things you guys can do. Everyone who is a little bit a hacker can do this. Just talk to the people. Be there for them.   Get out photos, videos, whatever and release it to the wild. This is what we're doing the whole day. We talk to people on the ground and that we are there for them and they can share their thoughts, their ideas, their fears. And this is why we, on the other hand, the people we can talk to, to take care of ourselves. So you can, as a group, specialize to certain things, but then remember to stay open, communicate about it. Like we do, we have our artifacts. We talk to the media, for example, not everyone, but some of us. Some do presentations and lectures and this is all a group can do to get formed as a body, to show that they are existing and to do great stuff, which is good for the people. On the other hand, I'm with geeks without bounds, which is a little bit more structured. We do sort of project management for continued efforts on these tools. So promising projects that come out of a random hacks. We have a team of volunteers that will continue working on it so that it actually becomes deployed and trouble-shooting, etc. Yes. Yeah. Now it's, well, time for the thank you. Seriously, thank you. Thank you, all people here. You're great. It was a great conference for me. Thanks to the comics guys, to the school factory, to the Maxxian who wrote our abstract. I just, I rambled that at Ella and she's like, is this what you mean? Yes, it is. How do you do that? Thanks, Clip Mata. Thanks so much. Thanks to the break pass crew for destroying Fluid Nexus. Thanks to all the ponies making us a funny life. And at least now we want you and we want your ideas on how people can get involved, how hackers can get involved and which problems they fear that we maybe answer your questions if you would like to help outside. Thank you. Can you talk a bit about sustainability? So how do you get kicks to show up on the fifth meetup and a year later and, you know, how do you get over the hype and actually start doing stuff in the long run? Sorry, I had really problems understanding you regarding your accent. Sorry for that, but can please someone? The question was, how do you make sure that people who get involved will stay involved for a longer time? Oh, thanks. Well, this is not that easy. At Telecomics, it's a kind of identification with the system Telecomics. You cannot plan a long term. So you need to reform every time we do an action. At the moment, when we started with Syria, we had other people then now involved in this case because people jump in, help a little bit and then jump out. This happens and this is okay because we're open. We can process this. Some of us now since the beginning with Telecomics were just quite a long time now. So this is in a way a kind of core team and they try to get people involved and to talk to them. So at least we are not never sure if there is something coming up, if there are enough manpower to do this. This is a flaw in our design pattern of our activist group. We're working on that flaw, but every good bug because it needs time. I found that doing regular, like once a month meetups work out well. If you do more often, at least in Pacific Northwest, people don't go because they figure they'll go next time. It really helps to get people in the field actually to experience what it is that they're addressing because then it becomes a part of their life. But the main thing for continued engagement is making sure people don't burn out. It's a really hard thing to tell people to go and sleep. When things are really bad. So like right after Christ Church, we still don't know what all is going on. There are still all these people missing and we still had shifts set up and it was mandated you get off of the chat and you go and sleep because if you're exhausted you're no help to anyone and then you burn out and then the next time a disaster or what have you hits you remember how awful it was for you and you don't want to do it. And so making sure that you are taking care of yourself is absolutely necessary. Hello. I just have a basic question. Whatever I hear sounds like a split up that any group requesting communication to secure communication tools of course gets a tailored solution which means you have an awful lot of solutions just nowadays in the field which are different just for about two, five, 10 percent but you have a lot of things and if a group tries to come together we simply start at the beginning to discuss if we should use Skype or Java or whatever and I see a tremendous split of efforts and a lot of if you want to call it products or solutions it doesn't matter but an awful lot of efforts spend into quite similar things. Yeah this is true. We have way too much tool outside. This is most times because a coder is coding something and then another one comes and says hey I would love to do this 10 percent of your tool in another way and though they fork and the next one forks too and suddenly you have five forks the same tool and in the worst case which is normal they do not work together so when you're doing tools and you find other people tools which are nearly doing the same and it's just 90 percent of what you would like to do or would you do please keep the 90 percent and keep it working and don't fork it because of 10 percent which are most times not that important. So makes the sense. That's one of the cases where it's also really nice to have someone with field experience helping to guide things and as good as we all are at coming up with very strange ways of getting around something and so we think that we know best sometimes they just want one thing and they want it to work they're like no really you want this no they don't and so it's good to collaborate and to offer other suggestions but maintaining focus that's provided by a person who knows what's needed. Just wanted to add a quick observation which is that social coding practices actually actually make this a lot easier. The there's a lot of sharing on GitHub among the folks in crypto.is so there's a lot of pull requests go back and forth people will fork something work on their own weird little thing and then it gets flowed back into the the main developers tree. That ends up working out a lot better I from what I've seen than kind of the old school forks as it were so that might be one bit of advice to pass on. Awesome thank you. We have the tools just use them. I assume I got a tool that might be useful to the people on the ground. How can I get in touch with them? How can I find out if it is really that useful as I think it is? Something like Camrobats for example where they test tools where they have different situations which might happen on the ground are replayed and where it can contribute even from here. On the other hand well the beginning is not that easy you need to make contact to people. We did it with this modem things where we faxed faxes with modem numbers and now people contact us so do well, evolve, do well again and then eat the cake. It is very much a still a who do you know because the trust based models are we've actually sat down and had a beer together and so I trust you so I trust your organization things like that. I'm happy to play organic chat client and if you tell me the things that you're working on or sort of I'll try to put you in touch with the best person I know that you should talk to but it's not a very like it's the best system and yet it's not at all. What software does you use for the slides? It's Prezi is the movement through it I like it because I grew up on comic books and so the fact that you can actually zoom out how do you You're in presentation mode but normally you could zoom in and out and everything and then I drew all of this other stuff so see how it's like one thing so I drew all the stick figures and stuff I broke my arm on on November 1st my motorcycle and I got in a fight with a car and not being able to type as fast as I can think really upset me so I took up drawing so now there's this thing If that's not clear raise your hand if you have a question you had a slide you wanted to have discussed right? Yeah Wow I wasn't Oh yeah I can't get this It was about this topic we asked you earlier that we wanted this topic so I hope you all have thought about that and I'm sure you all remember yeah so Hacking is a political act Hacking is way more politically than most people think or on the other hand nope it is not and it is important for us for our work to get to know how the hackers feel about these both tithes that we can deal with it that people who are working with people on the ground know in which way they need to ask and which kind of software they might expect so any comments, remarks on that I would be happy to hear them Not from the internet as you usually relay from the internet I think it's very diverse as in I see lots of different groups here either just caring about doing the technology bit and some just doing the technology because of the what have a political thing to do and some people see that the desire for how do you can use technology as a political act in itself and I think you have yeah not quite a diversity in that Super diplomatic response No it's good So any oh next remark I think if you make political decisions then those of course will influence how your tool needs to be designed and during the Kastor protests against the nuclear waste transport in northern Germany which is something that happens every year for 15 years now just for people who are not familiar with it there is a tool called Kastor Ticker which was basically like a Twitter feed on its own web page so it's a tool used to dispatch short messages with links and location data for where stuff was happening where people were needed and they had this one really strange and really funny message where they said that they were working on the DNS problems that had arisen for an IP range used by the police so the way that I think people were meant to understand it was that they had shut out police DNS ranges from using the tool which must have made quite an impact because police were known to use this tool and to find it more reliable than their own internal than their own internal ways of communication you know radio messages because those are all top-down and known to be really slow and so on the one hand this is a hacking decision you know to shut out an IP range is a technical problem but on the other hand of course it was based on the political factor of we do not want police in this case to be able to access this information so these questions you know they kind of influence each other and if you program a tool you have to think about could I possibly want exclude people from using this tool like the military in some case or like government agencies so you might leave some space for political decisions even though you don't want to make them I'm hoping that some of the tools that are coming out that are inherently transparent and inherently node structure will be subtly disruptive to all of these top-down systems because people look at them and they don't know how to use them and just by learning how to use them they learn the values of transparency that makes me happy in certain ways that's okay how do you manage the tension that exists here between having tools that for example need to interact with military structures or police structures like the classic example is crisis mapping and tools that want to be kind of you know sort of oppositional to authority kind of oppositional to hierarchies like how can you build relationships with those communities while also trying to kind of work around the sort of bad aspects of them well at least tools like crisis mapping have well a merit on the floor the merit is that anybody can see where is something going on after a disaster like an earthquake, tsunami whatever this is great this is helping everyone that helps the parachuting in troops who do well yeah the Red Cross whatever the technicians to see okay we need to work here we should need to send medics there and so on in a revolution I would not suggest to use such a tool if it's if a tool is highly transparent like disaster mapping you should not give it into the wild then you need to run it on dark nets or whatever which are not accessible by the not meant persons this is something we need to teach people on the ground in an ongoing revolution this is why they need the activists group from outside who built this for them in most cases so the same tool can be used in different ways and it is very important that people who are on the ground and find a tool somewhere on the net that they understand that this is not meant to be used in a revolution for example but I think this should be a little disclaimer somewhere in big red letters on the screen do not use in case of revolution something like this you see Facebook is well a wallet garden we know that it is easy to use it is very easy to use it is in a way not secure for people it is way too complicated to use in in cases of privacy issues but it is the best that people have we haven't built till now something better or something saying easy for them so they use what they have and we can complain as long as we want we just do not build better tools for them so they will use what they have all right for the people who know it it wouldn't be a surprise but I didn't think that it could work to control who is using your data because well digital vital management is just bullshit but my question is do you want to talk about the use of the tools or do you want to talk about also the design processes and the design process of the tools and at least both okay yeah I just wondering how the thing about don't use for revolution and but like using the tools use other tools or tools differently when you have a revolution line up with working together with military organizations like that's camp robert's okay so when you're dealing with when it's oh sorry when it's thank you when it's in a disaster then you have you are going to interact with the military no matter what hopefully in a way that's collaborative in revolution you're also going to interact with the military no matter what but in a different way and so until we have the ability that as technology becomes ubiquitous and as we're more able to help ourselves instead of asking for outside help we're from one organization especially the military the military is really good at moving things which is vital in disaster they're really good at shipping things it just shows up and it works but yeah it's it's treacherous territory of well if we made friends with you over here for a flood but then there's also refugee camp in the flood area then who are and was the military a part of why there's a refugee camp there it's it gets really shady and so it's not just about the the technology tools that we're using it's not just about those complicating factors it's also about the complicating factors of the people involved so there are no easy answers but that's why it's awesome okay first is Johnny I think we should we should finish awesome so um yeah thanks a lot for being here for listening to us for giving us input I hope you enjoyed our talk a little bit with the slaps and everything have a good last day here at the congress and see you all next year