And I guess without further ado, let's welcome Justin here to talk about threat modeling My name is Justin Goodheart. I'm from Olympia Washington part of the only mega group here hanging out helping out and I'm here to talk about threat modeling And try not to do feedback So if I lean forward I started out with doing development work for about 13 years and then at one point they shifted and pulled me over into the security team And so I got a chance to start trying to help developers write more secure code Better quality code and over the years. I've been able to help out with threat modeling and help out with secure code static code analysis different talks and pretty much just trying to be A good member of the community How many folks have done threat modeling before show of hands? Nice Those who didn't raise their hand. I could probably guarantee that you have done some form of threat modeling Good example is with traffic driving around obeying the speed limit signs doing maintenance on your car Being able to keep an eye out for the drivers around you Especially those who are driving erratically or who are on their phone while shaving and putting on makeup So what you're doing is you're putting in different controls to try to reduce the threats that could go against you So obeying the speed limit signs keeping your distance from the car in front of you making sure your Vehicle has been properly maintained so it doesn't break down on the side of the road those kind of things is what we are trying to encourage the developers in doing when they're building applications and When they're taking a look at implementing new systems. We want them to See what kind of threats are there see what kind of things to avoid see what they could put in place in order to try to reduce the Risk to the application. I missed a slide There it is So starting out I was going to talk about application threat modeling and then I have a couple of slides on network threat modeling as well Kind of a new area. I'm diving into Threat modeling is what I have most of my experience though So application threat modeling is approach for analyzing the security of application or system so good opportunity in order to be able to take a look at how it's documented how how it's built how you have put in the different mitigations in place and It also helps with the developers to get a chance to work with the security team In order to learn more and do cross collaboration because there's things developers have figured out to make things better They could help security and then there's areas where security gets a chance to collaborate with the developers to help their code That their systems be more secure So the process threat modeling process is pretty much breaking down the system Then what you do is you determine what threats are and then you go through and you identify the counter measures So mitigations or controls you can put in place to reduce the risk Potentially also eliminating risk Usually that means getting rid of the feature but Most time what we do with app case threat modeling is we start with the data flow diagram a good conceptual diagram of the system using some simple shapes the different shapes are external entity so a different system or Potentially like someone another company systems or another internal system that you're using or interfacing with Maybe even a third-party service You have a process. This is Where the work is actually done in the system So a function could be a web service. You can look at like the application itself as its own process The data flow so where the data is going back and forth and that's what you're trying to focus on And then the data store where the data lands where the file shares are or your data store like your database Maybe a flat file that you're storing somewhere with some data and then trust boundaries is something a little bit different from the Traditional data flow diagrams that threat models use and that shows going from one security context to another So like a good example on a web server You have different rights that you're running as then you would if you're connecting from a browser Or the settings that you have on a database is going to be different than your web server So you have different contexts that you're transferring from and so we want to show those lines In order to show when you're going from one context to another Good example of a data one of the diagrams for a threat model is just one of the canned ones I found online from Microsoft and This one shows a user browser the users coming in through a user interface service Goes over to user profile service that has its own data store And it also incorporates in a news feed service that it also has its own back-end data store But also can push out RSS feeds to the internet What we do is we start out with the diagram here And we sit down and we label each and every interaction going from one Process to the data flow or from the data flow across the trust boundary or going into another data store and We want to make sure and stuff that we could actually reference that one pinpoint and this was kind of a sloppy Normally the numbers are much better and you break it down More detail, but this was kind of overlaying Then once you have your interactions on the diagram you go ahead and you sit down and you show it each one of those steps where it crosses over from Across trust boundaries cross processes and you identify the stride stride is a different threat categories But each one has each of the different processes external interactors data stores, etc. Have a different potential threat area Let me go into that a little bit So stride is spoofing tampering repudiation information disclosure denial service and elevation of privilege and We'll see if I go back one Probably should shift these slides around so that I go through stride before talking about the matrix so Old school what we do is we sit down with this matrix and we break down After we've identified all the different elements on the diagram and we'd figure out what threats were there And so we sit down and we go okay We're going from this point to that point and we sit down and go okay They're spoofing and there is Repudiation and then we move on to the next one and so it's kind of a manual process using this matrix Later on I'll show you a tool that Microsoft provides for free that helps determine the threats automatically make it a little bit easier So spoofing is trying to pretend that you're someone or that you're something that you're not So a good example is if I was to go up and say that I'm Bill Gates I'd have to prove it and usually we do that through some sort of factor authentication Sometimes multi-factor sometimes single factor and you're trying to prove that entity Well, sometimes you're interfacing with another service some third party That third party you want to be able to prove that that really is who you're talking to and so you're trying to reduce the potential of An attacker or someone or maybe in a mistake of mis-configuration and talking to someone that you're not supposed to be talking to or Be someone that they're not Tampering this is where you're changing the data either across the wire or at rest or you're editing it when you're not authorized to do so so being able to Capture it across the wire injects something Also potentially compromising the files on the network share something like that Repudiation is basically a legal term for being able to prove that something happened Usually we do this for law mitigate it through logs in order to prove Usually also the third party a good example When you're buying stock and you go in there and you say okay the stock is coming down It's about $15 a share and you go ahead and you buy a hundred shares, but then you see it drop another $5 So you call up the company you say hey, I didn't buy it at $15. I really bought it at 10 Well in order to be able to reduce the someone trying to pull a scam or something over They have a trust of third party that time stamps the interaction How much it cost the time and you could prove that when you bought it you really bought it at $15 a share That's a good example to also the checks in the mail So you call up to or the Collectors call you and you're talking them on the phone. You say well the checks in the mail We'll wait for them to prove that the check was in the mail on that particular day the post office will stamp The envelopes that are going through the post office with their own time stamp And they are a third party that doesn't care if you pay your bill on time or not And so that works for non-repudiation another good kind of fun example Information disclosure is very similar to tampering except this time is unauthorized viewing of the data So you've been able to gain access to a file. You've been able to see what's going across the wire that when you're not supposed to Now this has also a lot when you're getting into confidential data that a lot of folks are not authorized to see Denial service is always fun. This is where Being able to prevent something from running be able to prevent someone from getting to your service being able to prevent it from someone Get into your website Denial service also has fun stuff with the distributed DDoS attacks or What happened last night? I guess with the wireless where? conveniently went down for a little while Elevation and privilege and this is where you can inject something in in order to be able to get more rights than you were authorized to have so some folks do this through Probably sequel injection cross-site scripting be able to gain access to different areas or be able to change something They're not supposed to be able to change or to try to change the context that they're running as in order to be able to have more rights admin rights other rights back about 2003 I think it was a trustworthy computing initiative that Bill Gates put out with a simple memo They started working on being able to show different ways of Identifying a scale for the risk of the system and they use an acronym called dread and it stands for damage repeating Reproduce ability I could say it exploit ability Affected users and discoverability and the whole goal was as you sit there with the big room of folks And you go down each one of these given it a scale of one to five And so you could sit there and you could debate over is it really a three? Is it a four? who wins and What ends up happening is is you end up going through and identifying what the risk score is for that particular threat and Lessons learned they ended up shifting it because there was too many folks fighting over the different scales To be able to go for a high medium low So if you sit down in the group and someone goes well I think this is going to be really bad because it will impact us it will affect 10,000 users We're going to set it as high and it's a lot easier to sell a high medium low than it is to go through each of these and have D of Five and a r of one and a e of three and what does that mean kind of thing? So high medium low works much better when you're going through threat models Then you go in and you start addressing each of the well Kind of bring it back Make sure that what's going on in my head you guys are actually understanding too so You've gone through you've documented the system you created a conceptual diagram You've now marked each of the interactions you've gone through and you determine what kind of my threats are Happening to each of those interactions and you've gone through and you've identified the risk of that particular threat Now it's time to mitigate it So there's four main ways of mitigating threats and it's kind of it's very similar to dealing with risk And you can mitigate the threat by adding in a control some way of you know to reduce the potential of that threat being exploited You can eliminate the threat, which usually means you're getting rid of that feature. You're getting rid of that system Sometimes program folks would come up to you and say we really need to have this system in order to track this data and Then they just want to be able to put it into a Microsoft access file Put it on the network share and think that it's going to be safe or even better Someone in the office admin assistant knows how to build access forms and they lock it down with a password But they keep forgetting that you just hold on the shift key Open up the access file and bypass everything so a little the risk is there so Sometimes the better bet is to either get rid of that particular data store and say maybe there's a better way or Be able to transfer it over like the next one where you shift it over to another system Or you add an extra insurance in order to be able to deal with the risk or you deal with a third-party tool Trying to transfer that particular threat over somewhere else and then there's always accepting the risk and accepting the risk could be very dangerous Folks are usually Quicker to accept the risk of a system a threat or of a bad system Then they are to actually address it because I think it's going to take more time more energy a lot more fighting just to do it right and so managers usually will Just unblindly accept the trick there is to make sure you document it Make sure they understand what the risk is and make sure that they understand what could happen if it goes wrong And even better is when you could get the development team to come back later And no doubt how they would fix it if they were told to go fix it in an event of a breach or some sort of incident But another kind of thing I picked up in one of my studies Sometimes worry is a sign that the risk hasn't been fully accepted or that risk acceptance was inappropriate So you start going down the path. They've already said we're going to accept the risk and Then now the manager is a little worried about it or the dev team manager or someone else release manager And they start to question whether or not That risk is worth it You should probably try to circle back around and reevaluate to see if there should be some other control in place Or what you could do in order to be able to reduce that risk So if you decide to go ahead and mitigate There's two main ways and stuff that you can mitigate a threat Design the security control that will protect it and that's where you go through the different common mitigations like sequel injection threats sequel injection threat use parameterized queries Your threats gone you make sure you could use Third-party tools like Andy the NAD framework, which does parameterized queries behind the scenes You can in some cases when you're doing more to the dynamic script incorporate something like sanitization and also input validation But the best bet is to use like parameterized queries and you put in that control of using parameterized queries that threat goes away Identify that we are accepting the risk And this is the second option and this one I also kind of note it's really good to document it and also what you would do if it was exploited because that Having that list there it helps you reduce the time after you've identified that there's been an incident Before you could have a fix in place or a hot fix in place another good thing when you're going through threat modeling with a team is to Sit down with them and say what are some of the common ones that we have and as you start going through the threat models Start making a list of the different threats and how you would How you mitigated it in that particular project This list eventually builds up into a nice library a reference library you could refer back to How do we fix it in the other project? What did we do last project or last year and you can start seeing okay? We saw this again. How do we fix it before this is a real quick easy way? Or how can we make it better and circle back and fix the application from last year? And so you get a chance in order to use this as a reference library But it also builds up the team because as you go through it more often they have a point of reference They can study up on it. We had lessons learned and then another good thing to do is to look out at the different articles and blogs and different feeds that come in talk about security related issues Because that Brent builds an awareness with your dev team Security team as well being able to know what's out there. What kind of events are happening What kind of threats are on the horizon? What are folks finding with the new technology that's coming out and What it does is it helps build that team up with their understanding and the better the understanding The more they could collaborate when they come across a particular threat in the system that they haven't dealt with before So an iterative approach. So just when you think it's over you get to go through it again in my organization a Lot of the developers They'll build the threat model and then they walk away from it and then they go build something else That doesn't exactly follow the threat model. That's a very bad approach So I'm constantly trying to get them back in the room when things are changing to Re-evaluate how they've addressed that threat what the system looks like Maybe you even recreate the threat model after the fact in order to make sure it's more accurate And then help identify if there any other any threats that we did not mitigate or we didn't know we're there and so Practice makes perfect and it really pays off And so as you get a chance to go through a few it also builds up more confidence with your dev team Because they've gone through it a few times. They're more familiar with it. They get faster at going through the threats and This is a diagram I pulled for more of an agile process But the idea is that you have that requirement that vision that you want to build Comes in you model it create the conceptual diagram You go ahead and you think I didn't identify the threats you figure out the controls You're going to put in and that's where you enumerate through the threats and Then you go ahead and you build out your mitigations And then you do a validation step and you could use different tools for the validation step like static code analysis Peer reviews are really good You also have the Chancellor and Poland security team if you have one in order to take a look at the code at the system helping them with the validation Quality assurance testers are really good allies to have when you're dealing with the validation step too Because they could find functional bugs that would also resolve in a security bug because if it's not working right maybe it could be exploited and So some essential questions that we want to ask while we're going through the threat modeling process What are you building? What does it look like? What is it using? What kind of platforms? What could go wrong with it once it's built are we going to deploy it out to the wild and just let it go or do We have a plan to maintain it What should you do about those things that can go wrong? So If you know that there's going to be the potential that Your internal server that's underneath someone's desk could go down Maybe you should move it to one of the servers in the data center or go to the cloud Which is a fun buzzword and then you go ahead and ask the question of did we do a decent job of the analysis? When we're going through this threat modeling process have that retrospect Retrospection of how it went How did we? Communicate as a team. How did we address the issues where the one areas that we need to improve in? Do we need better models? Do we need to do a better job of working together across the different teams? And get a chance in order to figure out how to make it smoother quicker and easier When we're going through that I kind of explained the more of a manual process of doing the diagramming Microsoft I mentioned earlier and a few other companies have some tools that make it a lot easier So that you could just do the diagramming and then it helps you with identifying the threats and then also documenting how you're mitigating the Microsoft threat modeling tool 2016 which they also now have a Prototype a preview for their azure version of a threat modeling tool to help out when you're doing azure type systems This one is free and it it works a lot like a visiostensils You just do the drawing of your system and then it determines the threats for you And you just go down and you show how you're going to address those There's another one called threat modeler threat modeler has a cost to it But they have three different edition Editions to use you have standard edition where you get a chance to draw everything out more of a single use on a single machine license You have a dev ops edition, which is supposed to help with The devs get a chance to connect they do their role security folks connect and do their role And you get a chance to kind of track it through your life cycle and then the enterprise edition is for more of the distributed keeping track of multiple systems multiple different projects and Then some other possible threat modeling tools that you can look up the secure CAD Iris risk, which some folks say is really I haven't got a chance to dive into it, but I've heard good things about SD elements by a security compass, so that was the application side I also want to note on the website for tour camp. I also have two other resources a Guide that talks about the different types of threats for the stride threats And then a list of their mitigations the common ones to use is a guide in order to help with the conversation And then also I have a networking resource guide in order to help with some of the questions that you want to ask to that So kind of shift gears a little bit from the application side And you're going to see my novice work on the network threat modeling side, so a Lot of research and to trying to find Someone else's work because plagiarism is cool And so I found really good presentation that talked about Documenting segmenting and then restricting is the kind of the roadmap for how do you address network threat modeling? the concept is Keeping your documentation up to date on your network map how the systems are configured so that you could use it as a Reference guide in order to make sure that things are right because that helps with the validation step When you can circle back later The segmentation in order to be able to make it so that it's not one big flat network that Everyone can't talk to everyone unless you have other controls in place like the certificates and There's some new stuff that's going on now where you don't even have to worry about firewalls and I don't know I saw some stuff at the RSA conference that was pretty out there But with the segmentation you don't want to be able to have something that has like confidential systems Or if you have secret or top-secret type stuff being able to be on the same network with all the Public information you want to be able to separate those out so that someone who gains access to the public systems Can't necessarily gain access to your more sensitive networks and then restrict and Instead of going with the defaults for your rotters and switches instead of going with the defaults for your servers Be able to configure and lock them down so that folks only have access to what they need to to get the job done And only to the areas and stuff that they're supposed to be able to get access to Some additional considerations So how many different devices are you talking about a home network where you're talking about an enterprise with? 19,000 plus employees with different servers and devices across the whole How many different versions of firmware you have to deal with if you have five different router types But they're all dispersed across and they all have different firmwares Is there maybe a chance there in order to get them all in the same firmware? Are you using the recommended versions in some cases? folks in different organizations personal experience Forgot to kept the routers up to date on the latest firmware And so a couple years goes by and you find this and it's a firestorm in order to go through and try to get everyone up To speed get it all the firmware to the right level and then do you have a good change management process in place? You know to keep track of the different versions the changes Where they're at and then also you don't want any hidden surprises So one day all of a sudden everything's available through shodan and you're scrambling to figure out why and there's been no changes At least nothing in your logs and then all of a sudden you call upon the group that works on it And we're actually they're now off the internet again So it's kind of weird when that happens magically Without any logs or any change or any record that they made any changes on the network or firewalls And so it's kind of scary because you never know when something might just pop up Another option I've seen some examples where folks have taken a network diagram for their network Threat modeling and they just converted it over to a data flow diagram and then use the existing tools that they had in place but they used it more with the strides and the dread and Some folks say that that is challenging because Application processes aren't exactly the same as the network So so questions Good please Very good question. The question was is how long how much time do a developer spend when they're on threat modeling when they're building a new feature and Depends on how hostile they are Some groups Haven't done or haven't been forced to do a lot of threat modeling before and so they'll drag their feet and they'll make Seem like it's the worst idea in the world just to convince management that they shouldn't do threat modeling in the first place It does happen but I've have Worked with multiple teams now stuff where we could get a new threat model knocked out in about an hour and Sitting down and just get a room together make it a team sport Pull in the folks that are working like the BA so they can answer some questions Pull in if you're dealing with like databases operations of the server's configurations Pull the operations folks into the room sit down and you just spend that hour going through and knock out the threats Make sure it's diagrammed accurately and then run with it There are the question was Between application diagrams and network diagrams the differences is that right? Yeah So with the application diagram you permanently are focusing on the data Where is it going in the system with the network? You're looking at The different IP ranges your different firewall rules Where things get diverse back and forth what kind of traffic you're looking at? Do you have a quality of service? configured so maybe streaming a video goes different than Someone trying to send an email but usually what you end up with is There's the logical network diagrams where you could show The IP address is going from one router to a switch or Traversion to whole network and then you also have some folks that will do their whiteboard network diagrams Which look like clouds with lines and some little brick walls and so it kind of varies there On the network side, but usually what you want to do is you want to have something that's accurate So make sure that they validate the diagram and then you just sit down and say okay Do we have the right versions of the firmware? Do we have it locked down properly? Do we have the right firewall rules in place? Have we worked with the firewall team and are to make sure that the configurations are there or is it set to any any? Which some folks still do but Yeah You remember The question was about how we see the threat modeling impacting the cyber insurance world and The cyber insurance world is dealing more with the risk management than the threat management of the applications But it still comes into play because some folks will say That they'll just go ahead and pay a little bit more for the insurance or a third party through an SLA will insist that they have their insurance a High enough in order to cover the expenses of the system or potential damages or how it would take in order to get it up in them a natural natural emergency or Some sort of attack The first part again real quick Audit compliance So kind of breaking that so the difference I think the question was So kind of the different what I understand and correct me if I'm wrong So when you're dealing with How much time do you put towards auditing and compliance? How much time do you put towards training and best practices? How much time do you put towards doing a threat modeling? Is that kind of a summary? Good So when you're dealing having those learning opportunities where you're saying that we're just not making you do this because we hate you We're doing this because we love you and we want you to grow Which threat modeling sometimes gets that way so Most of the time making sure to reiterate making sure to be open when they are hostile So you go into a dev team and they're First thing you want to let them know when you're the first time they have to go through a threat model They say that you're here to help you hear it in order to make it easier This is going to be a team sport, but then you want to make sure and stuff that Kind of try to carry them at the beginning go to the extra mile be there for questions be there for Walking them through it, but then also be able to point them to some good resources They can find on their own so the best practices and training side And then at the same time Being able to just actually tell them You're going to be audited later at some point You're going to be audited and this will help make it so that those are easier so you don't have to worry about that as much That helps with the app dev managers too because app dev managers don't like dealing with audits The downside though when you're talking about threat modeling sometimes they don't see the importance of it Sometimes they're hostile towards it or at the resistant And so get a chance in order to try to make sure that their managers are involved and that they understand that there's a Value added to the team and that's where it also helps with documenting the systems Because if they create a threat model and the data flow diagram and you say that that's good enough for their application diagram It helps them go wait. I don't have to create more documents I could just create that and then check it in with the code and I'm done please That's a very good point so sooner the development lifecycle the better Good example, we had a privacy office come down with their own system and so the developers were screwing in order to look good to the privacy officer and They sat down and they finally listened to me I'm like do it at the very beginning before you write up the system because that far too often they start coding They would have something in QA. They'd possibly have something in production and then they go wait a minute We're supposed to do a threat model on this, weren't we? that happens and so As soon as they know what they're kind of a concept of what they want to build Do the threat model right there at the very beginning and it's going to be much easier on them It's going to be much easier on everyone because it's no longer now a stop cap It's no longer a hurdle that they have to jump through. It's now just part of It's like a guide It helps them get a better picture of what they're going to be building how they're going to be coding it And so usually they actually like the threat model at that stage opposed to being resistant to it So, yeah, please The way I explain it to work You have your conceptual diagram of your system and then different features could be added on without actually changing the conceptual diagram But if there is a feature change that does change, that's when you want to circle back and revisit the threat model During the threat model conversation, we don't usually go all the way down to the weeds Usually we're talking more conceptual high-level, but by having the data flow diagram They actually know a little bit better what their process is going to be like and so we could talk about them when we're addressing the high-level stuff So it's a chance to be more familiar with like how is that function going to happen? How are we going to authenticate? How are we going to log? What events are we going to log? So those things are already been talked about in the meeting And alongside in there The developers always have my phone number, so they usually reach out, but that's a good point Yeah, if you're dealing with an external, sorry, the question was this for every process Do you have to necessarily have it in the threat model or you could go higher lab? If there's an external interactor, so you're dealing with it someone else's API You want to make sure that's captured because every time your system talks to someone else's that you want to make sure it's on the Diagram is a external entity But when you're dealing with the system itself usually what I tell folks is to aim the data flow diagram world Somewhere between a level zero and a level one to keep a high enough level to where it's not 5,000 threats. It's usually more like a hundred threats that you have to go through What is it happening is you could go all the way down into the weeds and talk about each and every function And you could diagram it and you could put it into like third modeling tools Or you could sit down with the matrix and identify all of them And it becomes bigger than the project itself. And so you end up having to go through a lot more paperwork a lot more Mitigations and you have to document so much that the whole team kind of gets bogged down But by bringing it back up to like a level zero level one right in there and enough in order to know kind of the main functional areas Like this is our web front end our web server area We're going to have our web services here and then we're going to have our data store in the back And so you have understand how the system flows and then you can talk about how you're going to deal with authentication with your authorization with Something like your logging with See what else also redundancy Resilient systems like load balancing different ways of handling the potential denial service attacks how those configurations are going to be When you're doing your whiteboarding What did that then need to software that could you know, you currently get higher and higher jail? Yes, it's very good point So I'm not as familiar with the the ratings as much but by having it done You could actually check that off. You could document it You could show it in an audit or review and so that helps when you're dealing with Trying to show it like auditors or trying to get ratings on how secure the systems are Yeah, because going through the steps being able to show that you've gone through the steps And especially when it comes to an audit But most importantly being able to talk through the with the development team be able to work with them And on how they need to improve their controls to make the systems more secure Yeah, it's a team sport you learn from the developers just as much as they learn from you And you get a chance to figure out how they approach the different issues any more questions So I have some additional resources again the slide deck is already posted on the tour site I have some threat modeling tool download Microsoft's secure development lifecycle resources and then also a book reference This is a pretty good book on threat modeling that I found before so Thank you very much for your time and have a good tour camp


Yeah, so thank you and welcome to this last talk this evening I think there will be a film at Zero o'clock, but the last talk for this evening is for Maxwell to antenna arrays You probably all know Maxwell's equations the four equations I actually like the idea that was for more less simple equations. You can really explain a lot of stuff And I'm a communication engineer, so I will stay in three dimensions Back when I was studying I actually also visited the lecture about relativistic Electrodynamics which is all this Maxwell in four dimensions and I also I passed it somehow, but yeah, what you can see here on this nice picture is A am broadcasting station with an am antenna array. I think it was medium wave here In Brazil, it was I think in Rio or Sao Paulo. I was more working with stuff like this At the moment I work as a science journalist And it's quite interesting how a lot of stuff like mobile broadband and also things like radio astronomy Coming together in the field of antenna arrays, so I will get the the topic to this and Also, I think for everybody some fundamentals of wave propagation and how antennas are working which now everybody is has in it His or her pocket. It's very handy in many situations So Here are for Maxwell equations. We have Gauss law. We have Gauss law for magnetism We have the law of induction paradise law of induction. Oh, I think could it be that this microphone is on? No, okay, good and the fourth one is I'm past circuit law here and a bit more details so Gauss law of Induction actually describes the relationship between a static electric field and the electric charges that cause it So here we have two point of charges And the static electric field points away from the positive charge on this side here towards the negative charge and Very easy example as a capacitor You all know this you have your two two sides of the capacitor where the charges are and then you have the electric field in between a little bit of mathematics so here we have the This nabla operator with the C that is the divergence of a vector It's a dairy rate of each value In in space so in X Y and Z coordinates And then they are added up So actually this measures the magnitude of a vector fields source or sink at a given point And if we later come on to free space propagation This row here so we have no charges in free space So this row becomes zero and you can simplify this equation So the next one Gauss law for magnetism is the divergence of the magnetic flux density equals zero That states that there are no magnetic charges or magnetic monopoles You all probably know what happens if you break a magnet into two parts So you've got two magnets with a plus and minus pole Yeah, and the this equations state that the magnetic field lines so the circles here Neither begin or end but make loops or extend to infinity and back The third one is paradise law of induction This one describes how a time varying magnetic field creates or induces an electric field This lengthly term here is the curl of a vector. This actually describes the direction So it's the direction which is like orthogonal to the other ones a good example is Where this law is working is an electric generator So for example, it has a rotating bar magnet which creates a changing magnetic field and Which in turn generates an electric field in a nearby wire so you get your electricity by moving your magnetic field and the last equation here is Ampere Ampere's law with max worth addition and this one states that magnetic fields can be generated in two ways one way is by electrical current and this was the original Ampere's law and Max worth addition then added that also by a changing electric field a Magnetic field can be generated and this addition So this is this part here like the the e field the electric field Derivated to the time so the change of the electric field This is especially Important because it shows that not only does a changing magnetic field induce an electric field So this was the law of and that law of induction But also changing electric field induce Magnetic field and therefore these equations allow ourselves sustaining electromagnetic waves to travel through empty space So on a whole we have those four equations, please keep them in mind for a moment. I will come to back to them later First some history because it's exactly 150 years ago that the These equations or max worth paper a dynamical theory of the electromagnetic field were accepted for publication by the Royal Society but some remarks what was going on and About technology at this time So here the average lifetime of a light bulb at 1870 was around 10 hours The first central station providing public power is believed to be one at goddamn Sorry in the UK and it was switched on in 1881 so probably Maxwell didn't had electric light when he write wrote this paper There was also a lack of mathematical fundamentals. So already Faraday which which had Which were who was also researching a lot in this field envisioned in 1830 and mysterious What he called a mysterious invisible electronic state surrounding the magnet what we were today called a field or a vector but vector calculus was not invented yet Faraday also Realized that light itself was a magnetic wave, but shaping this ideas into like And a complete theory was way beyond his mathematical abilities So actually makes or also didn't had 20 equation for equations, but he had 20 equations So you can see some of them here on the right side and it took another 20 years until they were understood by someone else and It was this actually self-taught British engineer metametrician and Physicist heavy side who put the equations then in their present form like and to this four equations Some years later Hertz Heinrich Hertz brought the Experimental proof of Maxwell theory He verified that electromagnetic waves exhibit like light like behavior of reflection refraction diffraction and polarization and Also that the speed of light and that of electromagnetic Radiation seemed to match up pretty well. So the proof came up that light also is a an electromagnetic wave So back to Maxwell's equations If we come to free space propagation In a vacuum we have no charges and we have no currents So this row here in Gauss law equals zero and the J in an ampere circuit law also equals zero So the equation simplified to this one Which looks pretty Symmetric Except of here's the miners and here are this permeability and permittivity Which can be summed up to the speed of light here see When we then want To come from those equations perhaps to something that looks more like a wave like we know this waves are like Cosinos or senors What we do is we take the curl of the curl equations I put those Maxwell's equations here and to the side I will show it here for the law of induction for the if a if field Electric field for the magnetic field. It actually works the same So we take the curl of the curl equations Here Do some vector calculus? So the curl of the curl of a vector equals this one is the gradient of the Divergence of a vector minus the square gradient of this vector Then we come to this equation here Here our divergent we see this up there equals zero though all this stuff equals zero and this part here Pretty much looks like this part here, so we can change this actually the beamers stealing some lines I think so this is also a division here And we end up in Then we put this to the other side and we end up in those work hard the wave equations This are still two-part share differential equations The simple solution of those equations is a plane wave, which then you can see here or Something is happening here Yeah, and they are already pretty much looking like waves like we get Here our amplitude here the e zero we get a cosy nose like the the wave form Then we get our omega like the frequency Depending on the time the K here is the wave vector and here we get our dependence on the location and a face This wave number K actually represents the rate of change of the face and is also pointing in the direction of Propagation a plane wave can be seen here for example, so We got a e field and an orthogonal magnetic field plane waves are defined like to have a constant frequency The wave forms are parallel planes of constant peak-to-peak amplitude and all this and normal to the face velocity vector and Such a plane wave always have a pointing vector The s here the pointing vector represents the energy flux density of this wave And is Also in the direction of propagation, which is always orthogonal to the boat to the two fields to the e and the b field Then every wave has a polarization the polarization is defined as The alignment of the e field the electric field so for here for example, we have a horizontal polarization And we have a linear polarization here because we have only parts In one direction There are also other forms for example here. You can see a circular polarization And this occurs when we have two orthogonal e components components with exactly the same Amplitude which are 90 degree out of phase and those two waves actually then behave like a wave circling around For example here is an antenna which can be used to receive a circular Circular wave It's called a qf h at what three feeler helly Coedal or something like this antenna and I built this one for receiving like some No, I weather satellite pictures which are sent out in FM and it's kind of very cheap to build this antenna with some wave some waste pipe some copper cabling and The receiving can be done for example with a really cheap software radio such an RTL SDR And with this you can see Europe kind of from above you can show you one One picture, which is also not so good on the beamer here. So this is the RTL SDR This is this qf h circular polarize I polarized antenna in the countryside Here you get some open source software for receiving the signal. This is the program is called GQ RX Which is really does nice FM demodulation and then there's a program to to To calculate from the signal the satellite Picture, which yeah, it's just an FM modulated signal and here for example there are a lot of clouds here It's this is Italy like the boot of Italy can be seen here and Yeah, here's What this is the Mediterranean Terrainian with some clouds and this is kind of here central Europe So Was kind of 20 25 euros you can just see Europe from above. So if you have some spare time You should really go out and hunt for some satellites But back to some propagation first So we got the the vertical and we got the circular polarization There's also elliptical polarization that comes up If you've got also two components like the circular polarization, but they have different amplitudes So we don't have the circle, but the ellipse elliptic ellip. I don't know I'm Regarding polarization if you want to receive for example a horizontal polarized signal with a vertical polarized antenna You always lose some signal power Now for example, if your circular antenna Is circling in the wrong direction of the signal? Um It actually you got something It also depends on whether you are in or out or because every reflection and all the scattering and stuff Also manipulates your your signals. You don't only have a vertical component But often it makes sense like to move the antenna a bit if you have bad signal or in many modern Equipment you have like to receiving antenna that do some kind of receiver diversity to get both components of a signal if we take a look On free step is free space propagation in the real world We assume we have a certain distance between the transmission antenna and the receiving antenna and It's good to assume that this distance is Exceeds the antenna length and also the wavelength by several multiples because in this case you can You can your Pointing vector like the s from before Seems to radiate from a single point and We can use the Fraunhofer far field approximation just called which simplifies a lot because We can divide our term of propagation like the point The the energy flux density here In a spherical propagation part so you can This can be seen in the figure here We can divide the propagation the area on a sphere cross So here we get a small area and then we if we move farther away from our transmitting antenna here in the middle the area on this fear grows proportional to the square of the distance and At the same time if we use the density this one drops inversely proportional So this behavior is the 4pd Square in this part and then we have the three-dimensional profile Coming from the antenna pattern So on the whole this becomes quite easy for propagation You also know that Higher frequency do not reach as far as lower frequencies and this is caused by the antenna aperture the a Here equals the pattern gr the antenna pattern gr and here Lambda square or wavelength divided by 4p And the antenna aperture Determines how well an antenna can pick up power from an incoming electromagnetic wave and a tire frequency Can we seen like that the antenna in proportion to the distance is smaller and therefore we Cannot pick up as much power And then yeah, we can put in here No, that's afterwards then at the receiver here we get the power PR This equals the energy flux density, which is like the wave in the in the free space Multiplied with the antenna aperture then we can put all the stuff here the s and the a In here and we got this term for our receiving power At the receiving antenna now dependent on the distance and also on the frequency and Then we one term which is often used is a freeze Transmission equation that defines the ratio of power available at the input of the receiving antenna to the output power of the transmitting antenna And Here the inverse factor of this equation is called The free space loss which is actually the minimum loss you always have if you have two antennas Sending around something Mostly you get additionally Reflections diffractions at a nation's from the atmosphere and so on but yeah, this is the minimum loss you have when it then Comes to antennas We always like this antenna patterns because they describe like how much of the energy is sent in which direction This pattern depends on the current distribution on the antenna Because here we really we have mostly some metallic materials, so we get some current so j isn't Equal to zero for example here we get a half lambda dipole The calculation of the pattern is then based on max-worth equation again You normally work with a vector potential and everything in circular coordinates and It becomes a bit complicated So fortunately, there are a lot of nice programs who do the work for you This year was calculated with for neck to which is a really nice program. It's free and I think it's not open source, but It's also for windows, but it works also fine with wine and the linux It is based on the numerical Electromagnetic code, which is the neck here in between And the code is based on the more method of moments Solution of the electric field integral equation Um Neck was originally written for the US military and is then put under public domain It's a bit complicated to build your own Antennas with this so it's it's possible, but yeah probably There are lots of very expensive program, which makes it easier But the cool thing about this program is that it has many many example antennas with which comes along with a program So for example also this QFH antenna I showed before for receiving the NOAA weather satellites Was also already included in the examples so here you can see the main window of the program Then you can go here to calculate then you get this windows here you can choose Yeah, I want to calculate the far field pattern of my antenna then you can just go to generate and Then you get a nice you get 2d patterns, but you get also get a nice 3d pattern for example here it can be seen this antenna is For this weather satellites who are running like above you from horizon to Horizont so you want to have an antenna pattern which also goes up from horizon to horizon and Which also does the circular polarization so this Fits pretty well An important principle when it comes to antenna patterns is the interference between different signals So if you get for example two waves you always have There's always constructive and destructive interference so for example When it comes to interference here, you can see a swimming pool Interference done by I think this is a French astronaut who is doing this like putting two Arms in the water and then this the waves coming from two sides are interfering by each other so we got here we got some peaks of the of the water and Sometimes it goes down Here if we got two waves and they are in phase so which means they are Starting at the same time and location they are causing constructive interference and if those two waves are 90 degree out of phase which can be seen here you get destructive interference so they cancel each other and Yeah, for anything in between you get also get some some interference in between which makes this Resulting signal a bit smaller or a bit better a bigger depends I also found this nice picture of two interfering waves coming from two points here on Wikipedia So can take a deep look Okay, thanks a Very descriptive Antenna for explaining the interference stuff is a Yagi antenna You can see here for example Yagi antenna built for the Freifunk wireless Network like to get a directional antenna for two point fee for gigahertz You always got a driven element which is this one in this case and then you get some parasitic elements Director here now the directors are in front and a reflector here in the back The parasitic elements are receiving the signal from the driven element and at the same time also sending it out Again and they are not exactly resonant, but somewhat shorter or longer than our half lambda Wave length and this creates a capacitive or inductive reactance and this reactance modifies the face of the elements current with respect to the to its Excitation from the driven element so You can see this for this two element Yagi. We got the driven element and the Emission from this element and then we get the director and the emission from the director is Out of phase in such a way that here to the front of the antenna we got a constructive Interference so the signal is getting getting bigger and To the back The backward emission we got a destructive interference So we get less power to the back and more power to the front as wanted So What would for example happen if we connect all this Yagi elements here to a source and then we could for example Manipulate the face of each element in G individually So we can see this here This is called then a phased array Here for example, we have a lot of small antennas then we have a face shifter. So it's in German here I only found this in German and Then by manipulating the face of each antenna we can change the direction of this array or The direction of propagation Here is another example we got two antennas if We put signals on each antenna with the same face the main lobe of this array equals The main direction of each antenna. So it's going straight forward in this direction in the other case if we Delay the other face of the upper antenna slightly Then the lobe moves up the lobe of the antenna array moves up and The gain of the resulting antenna Always consists of the gain from each single antenna and then there is an array factor So if you have a lot of antenna you can create Very high antenna gains and by manipulating the faces you can then move the lobe direction as wanted There are different techniques to do the Face shift the first one once were in hardware. So you get just longer cables for example Carved in and brown invented this technique in 1905 Then it was mostly used as often for military purposes For example, it is still highly used in radar systems It was later then also adapted to radio astronomy Leading also to a Nobel Prize for physics for Anthony Hewish and Martin Ryle for their interfore metric radio antennas But more on this later An interested thing is When you mix or like some time ago software define defined radio this technique came up in a large Scale and if you mix this was antenna arrays you get a really a lot of flexibility Into this faced arrays You can for example Manipulate the face of each signal and software You get a very flexible for example beam forming Depending on the face you set in software you can change the direction of the beam and also mix this with MIMO techniques so with MIMO multiple input multiple output you additionally do some pre-coding on each signal from coming from from each antenna And with this pre-coding you try to take advance of the Channel properties for example in a very scattering environment a channel Has a lot of different uncorrelated path is so you can Increase the data rates for example. It's also used within the newer wifey standards It's also getting cheaper. So Not only the military say I can use it now also like the mobile for mobile broadband They are doing a lot of research at the moment for example for 3d beam forming This is can be seen here in this picture. So we got our base station when we get one beam here down and several beams to the skyscraper here and the idea is for example To cover different levels of a skyscraper with different beams on the same frequency So they are always afraid to how they shall transport all those data those mobile data So they can actually reuse frequencies with this beam forming So the latest headline came from ZTE and China mobile Which who did a test with the 2d arrays with the total of 128 antennas Yeah, as I already told this software faced array technology It's also used in radio astronomy There it's for receiving signals and that's also very general An antenna always behaves the same no matter if you if it's used for transmission or reception. So also You if you you know that you need a really precise time stamp of each signal on each antenna and then you can like Process the signal from the different antennas with different phase shifts Depending on which direction you want to you want to receive the signals from and Yeah, you can get a really good Antenna gain by using a lot of antennas And that's also important To distribute them on a long way the radio astronomers actually have the problem That to explore signals at lower frequency The telescopes need to be really really big to have a good resolution And it becomes quite Unhandy like if you if you see the The dishes They already started like building this dishes in wellies But then it becomes quite unhandy like if they want to get a signal from another galaxy Which is not right above the dish, but at some other location. So it's just Not possible to move it anymore And The angular resolution of a telescope here depends on the wavelength Divided by D D is either the diameter of the telescope or it's the baseline So the length of the maximum physical separation of the telescope in the area and a nice example is for example the Lofa the low frequency array Because they want to observe radio frequencies from 10 to 250 megahertz So you got really kind of long wavelengths from 30 to 1.3 meter So what they do they build a lot of different Stations and distribute them over half Europe It's in a total it's around 25 down small antennas Concentrated in 48 large Stations, they are also still building new stations. I think the last one was Kind of in last summer. They they built the latest station in Germany near Bremen or Bremerhaven something like this Within Lofa the angular resolution Goes down to zero point two one arc seconds and the wider space line is something like 1,000 Kilometer and at the highest frequency And if you build such stations In software it's also built with the software radio technology also the data processing becomes quite interesting Because perhaps you remember you get your audio CD you get 80 minutes of music you get around 700 megabytes of data You can hear From 20 to 20 Hertz to 20 kilohertz. So you get like around 20 kilohertz audible bandwidth Nyquist told us that we need the double sampling rate And so we often use the forty four point one kilohertz 16 bit and two channels Here we got frequencies from 10 to 250 megahertz Which makes it quite? Bigger bandwidth and we get got like 25,000 antennas which all generate a Lot of data what they then Do is they do a kind of preprocessing of the data at the station already Like they have to decide before which direction they want to to get the signals from and then they do this Correlation of the signals already partly At each station and then they sent the date to the Netherlands to Groningen Where a blue gene supercomputer does the final processing from the distant stations then This loafer telescope is also a pathfinder project for the square kilometer array This one is in pre-construction phase at the moment It's a It's planned to be built in Australia a part in another part in South Africa The plan is to cover a frequency range from 50 megahertz up to 14 gigahertz in The first two phases of the construction So here you can see an animation. It's not really built of the dish antennas And phase one shall provide ten percent of the total collecting area at low and mid frequencies by 2020 20 by 20 20 and phase two then Shall complete the full array at low and mid frequencies by 20 25 and then phase three shall go up to 30 gigahertz It's actually three telescopes because of the of the huge bandwidth So two dishes here you can see the animation of one of the dish antenna arrays and For the low frequencies you get an array of dipoles The maximum baseline of this antenna are 3,000 kilometers and the collecting area is one square kilometer. Therefore. It's called square kilometer array And within this project also the main challenge is the quite huge amount of data. I Had an interview with the technical director of this SKA earlier this year and he told that they are they are Blending to have more data than the internet carries today on there all together on their stations and All this data has to be processed transported and made available for the scientists They plan to deploy like fiber optic with the length that would reach around the world twice And they actually trust in most law to process all this data though They wait until they buy the hardware until Yeah later It's really needed Um the scientific goals of this this Array this telescope is Between others the 21 centimeter hydrogen line that shall map a billion galaxy Out to the edge of the observable universe They will do research in the processes resulting in the galaxy formation and evolution will be done And research and the evolution of cosmic magnetic fields and The epoch of free in ionized ionization after the Big Bang But yeah here all This stuff is again connected somehow to relativity creation of the universe So I will end here Thanks for your attention Yeah, and if you have some questions I can try to answer them Okay As always there's four microphones one there one there one there one there just line up if you have any questions Maybe you need a little refreshment and vector calculus. Maybe you just want to know some physics Just ask Do we have questions from the Internet? Oh The Internet is already asleep. Okay. Go ahead when when you were getting the Images from the satellites, could you rely on good documentation or was it a lot of trial and error? No, there's actually a kind of good documentation in the Internet Yeah Just a search around for no satellites and SDR I also wrote an article about this in the hardware hex, but it's not online unfortunately So you have to buy the magazine Okay Does the software you presented? consider cases of non-free propagation so if Electromagnetic active medium is present in the near field This antenna software I Don't think so actually You can you can do like areas like what's the name? Flächen anten in German But I think that don't it doesn't support like different materials of the surrounding space But I'm not quite sure so there's also a lot of documentation on the website from for neck to perhaps Better have a look there Thank you Okay, to the right, please. Okay in the plot with a Yagi antenna the empty field amplitude of the Passive element was higher than the field Field of the amplitude of the driven element. I wonder how that could be. Is it magically? Producing some energy or where where did this bigger field size come from in on that plot Yeah From Wikipedia No, actually it shall be smaller because yeah, you always have some some losses When you when when the element received and then again sent the stuff. So yeah, you're right Okay Yes, how do you deal with noise being generated by the antenna itself? Okay, can you do other ways to actually lower them and the noise of the antenna itself or are there other ways of Making sure you have the maximum Secret noise ratio You mean in a faced ray or in this yagi or for example or with with the with the dish antenna like In the later square kilometer array. Oh I don't know actually I'm not so much Into the technology I think they have to deal with it because probably they will catch up a lot of noise but yeah, probably Yeah, often like often your noise have some your regularities. So you you collect Large amount of signals and then you can kind of calculate the noise out So that's how you normally do it and yeah Okay, internet We have two questions here one is Is intercontinental SS TV possible and if yes, which type of antennas would there Needed two twosies and how big would these antennas be?  Yes, someone said yes Okay, I Actually, don't know what slow scale TV is No, as a TV is moving less TV is possible an HF so intercontinental as a TV is possible but You need time because it's extremely slow because of the low frequencies So you use this ionosphere stuff reflecting stuff at high frequencies. Yeah Okay on 20 meters the right place Maybe I missed something but What is the connection between all this Maxwell stuff and the face area stuff? because this face area you can use with Conventional waves like ultrasonic or something Where's the connection between is this Really used for this face array. This is only a superposition of Elementary waves in the far field. So I don't see the connection to the Maxwell equations there So the Maxwell equations like explain or wave propagation So it doesn't matter if you have radio frequencies or light. So they are kind of explaining the wave propagation and then I Try to explain what you can all do with a different field of this wave propagation and regarding to antennas but the This what you use afterwards It's not not a property or it doesn't use a property or as a unique property of radio frequencies For this beam forming stuff. So this is Without your waves for example, yeah That's right. So, okay Okay It's on would you all will be always be the case that I would need multiple receivers to make any use of a receiving array or Could there be any way to use this one receiver? with an internal array And somehow Calculate the direction So just if you just use one receiver of the antenna ray and and to do what to I Don't know if you want it like a directional reception or something like that This is always the case that I I need to one receiver per one part of the antenna Yeah, you need some kind of construction that does the directivity So you can you don't need an antenna array. There are also other forms of antennas which are directional but within the array like you need different signals to get This different phases like to to create your directivity then Please go to the mic if you want to say something because the stream can cannot understand you Well for the case of antenna arrays You don't need several receivers at every antenna part You can also combine the signal and hardware with the phase shift is like she said and After you have combined the signal over some power combiners. You can just put it into one Single receiver, but you have to do all those fancy phase shifting stuff in hardware And that's hard is and to combine the signals after you have digitized them. Thank you Okay, thank you any more questions, okay internet Yeah, I have one question about the Maxwell equations and This question is is the second equation meant as statement on a specific point or of the whole file On what on a specific pulse On a specific point or so who filed You mean field a field. Yes You It's it doesn't need to be a point. So for example, it's also if you've got capacitors you can have rectangular or whatever form of I Know this was the first one. What the second Maybe just show the slide so we know what you're talking about So so it was the second equation, right? Yes, and then if it's one point or if it could be a field If if this equation is meant as a statement on a specific point or who field Sorry, I don't understand the entire field B is the magnetic field Not a magnetic point which does not exist Thank you Technically this is a statement about the sources of the magnetic field So the second Maxwell equation just says that there are no sources for the magnetic field Which basically means there are no monopoles Do we have more questions? Okay, thank you. Thank our speaker again, please


The Nigerian Security and Civil Defense Corps have dissolved all anti-vandal teams nationwide. NSEDC Commandant General Med Audi said that the dissolution was part of the reorganization efforts of the Corps and the way of redeeming the image of the service. He added that an investigation is still ongoing the issue of extortion of oil marketers by an official of the service. Hello. Hope you enjoyed the news. Please do subscribe to our YouTube channel and don't forget to hit the notification button so you get notified about fresh news updates.


I'm Cyrus Hagee, I was the past president of Portland Rotary. Portland Rotary came up with the idea to do this clock project as a way for us to give back to the community. We were looking for a project that would be something to be visible that people would recognize Rotary for, and this became the project. I had a chance and I have a tenant named Scott Nash who is the illustration instructor at Maine College of Art. And I said to Scott, I got this clock project, what do we do? And he says, I've got these artists and they're going to design artwork to put on the clock. So if you remember last winter, we kept changing the clock faces to draw attention to it. And it actually was so successful, it actually solicited unrequested donation, maybe $5,000 was mailed to us without even my getting to go knock on their door. Thank you very much for doing that. So we did the yard, we drew attention to the clock, we raised the money, the clock is here. It's a very interesting clock. Inside is not a motor that turns the hands like a normal clock. Right inside here is a digital transmitter that reads the GPS network every minute and then adjust the hands according to the GPS network. So come daylight savings, it will correct itself or going off daylight savings will correct itself. The power goes out by 12 o'clock noon the next day it reassets itself. So it's virtually maintenance free. It will be a long, long time until we need to go to Portland downtown district to dip into the maintenance fund. But the most amazing thing was getting the chance to work with the city. And we've got some gentlemen here from public services. I'd like to give them a round of applause. They were able to, with virtually no instruction from us, translate the plans, put a new foundation in, put a base that the plows won't hit. And when we brought the clock in, we swung it in the position and set it exactly down perfectly.  How do we get it off?  A week later we ran wires over from that panel there and had the clock activated. What a team effort. Much, much appreciated. It's a real pleasure to work with you gentlemen. Charlie Poole from Union Wharf came up with his boom truck to swing it into place. It was sort of, everybody was here having a good time. Plus we had lots of fruit sellers and veggies being sold on the same day. So I'd like to just briefly recognize the donors. Just to say thank you. Obviously the City of Portland was one of the major players in the foundation work. Portland Downtown District for the maintenance, Key Bank, Estonal Suspense and the Press Herald, Main Community Foundation, Drummond & Drummond, J.B. Brown, Portland Museum of Art. That was a real fun ask. I was asked about that the other day, how I did that. Since they always ask for money and never give it away. Portland Rotary, Justin Alfon, Jensen Beard, Gardner Henry, Bobby Monks, Harry Sawyer and Nan Sawyer who obviously passed away recently who would love to be here. So give her a nice thought. Alessandro Renau, a long fellow of books, was here day in, day out providing us a ladder so we could get up and change the clock faces and use their storeroom. Joseph Powers, UBS, somebody named Anonymous, Bernstein Schur, Freddie, Freddie Flaherty, Oldport Wine Shop, David Snow, Norman Nelson. And thank you very much for your donations. We were able to raise the full $25,000 to boot the clock. And without your donations we couldn't have done it. Now in honor of this project I have prepared a token to give to the city of Portland. It is a golden hex wrench. Since the clock does not have a key, I thought why not have a golden hex wrench. So to Mr. Mayor, here is the key to the clock. I want to thank Cyrus, the Rotary, all the other people that contributed. You know, things like this happen in the city of Portland because we have partnerships and because we have all these people in the community that step up and say we want to make a difference and they want to focus on something. And this is an iconic structure in this part of Portland and it deserves this kind of attention and it deserves this type of renovation and we're just tremendously happy that the Rotary and all the other civic organizations and groups stepped up to make this happen. And I do have a key to the city that I give out to people all the time. This is the first time I've gotten a key to the clock that is actually a wrench. But we'll make sure that we put it in the appropriate place and if we ever need to use it, we'll be able to. So thank you very much. Mr. Mayor, thank you so much for coming and that's all folks.