Good afternoon. It's nice to see everyone here. My purpose today in talking, I will not be discussing any cases that Jennifer Granick and EFF talked about earlier today, so that kind of fits in well with what they presented. My purpose today is to give you some cases and things that have happened in the law and present it from a perspective of what the judge is looking at. So I'm going to be talking about the facts that the judges are looking at in their cases and the rationale that they're coming with so you can see how they are dressing and how they are treating this technology thing that is still new to judges but old to you. It's nice to see everyone. I was having a conversation with Marcus Sacks back in DC and I said, you know, it always amazes me how many people actually come in from the technology field and want to see what's going on in the law because these packs are always talked. And it's always nice to see you people here. And then Marcus said, yeah, all the other rooms are filled up. They got to go somewhere. So I said thank you for that endorsement. I appreciate that, Marcus, on that. But what you may want to see but what the courts do see is that you are very special. In this case back in 2005, to enhance a sentence two degrees, they said that using computer skills and a nefarious method can increase your sentence by two degrees on the scale. Some of the examples they also said for people using skills to commit crimes, pilots, lawyers, and I like the demolition experts, too. So you're in good company with those folks. One aspect that just got nixed was that if you used a proxy, they were going to change the sentencing guidelines to say that is a skill requiring you to get a degree enhanced sentence out there that did get knocked down. So if you're using a proxy, that doesn't mean special skills. The agenda. A couple of cases came out before I gave my CD to DEF CON. So we're going to talk about a couple of the latest, greatest cases that came out. Look at some cases talking about an encrypted hard drive. Consent is always a big thing when you're doing computer investigations, destruction of evidence, revoking that consent. Some border searches. Earlier, EFF had mentioned that they wanted to do this conference on a cruise ship in international waters and thought that would be very interesting. And that'd be great for all the things you could do in international waters, not violating any crimes. The problem is when you come back, yeah, that's when the border search comes in and there's been some interesting cases going on with that. A hot topic has been cyber warfare. And I've lived that in the past, so we're going to talk about some aspects of cyber warfare and the definitions that we use when we go in there. And one of Jennifer was commenting on how she won a case and all dealt with a comma. And in the legal world, definitions and the word you choose is critical. So we're going to talk a little bit about that. Look at a cyber spy, some cases, some ex-spouses cases, putting keystroker things on there. Always give us some good cases to look at. A little bit on responsible disclosure. What makes a hacker? Hey, that was the Klexi case with the two operating systems. So we'll skip right through that.  And I just want to give a little bit of a tip on what I think for the future holds for both the legal world and the tech world. I am with the government, but I'm here in personal capacity. But anything I say is all personal. Any errors I make reside with me and not the government. So I got to give you my disclaimer. And one other aspect on that disclaimer. If you have a town with one attorney, an attorney can make a good living. If you have a town with two attorneys, they can make a great living. And that's kind of, we'll touch upon that a little bit later too. And that's because if I ask you all what 1 plus 1 is, a lot of the scientific and the math background that you'll give me, you'll say 1 being a positive number, 1 being a positive number, that sets 2. If you ask a lawyer what 1 plus 1 is, they'll say, what do you want it to be?  I worked for a judge for many years and we used to schedule our motions on Wednesday afternoon. And when we had tough cases, we'd schedule 2 for about a 6 hour period. They check in. The attorneys would tell me about their case. I had an attorney come in and give me all his facts. And I had another attorney check in giving me all his facts. I called the case and they both stood up and I was amazed. I swear I thought they were in different cases. And that's an interesting thing that you need to tuck away when you're doing this. When Jennifer was mentioning that a TRO, a temporary restraining order, was filed on a Friday afternoon after hours so no one could respond to it, that's how all temporary restraining orders are filed. You do that on a purpose so that you get the injunction that you want without the other side being heard. So you need to remember these things on how this works back and forth between attorneys. Your attorney is going to take your facts and give them to the judge in the best light they can. The other side being corporate counsel or counsel that the corporation has hired are going to give the facts in the best light to the corporation. So when a corporation comes in and says, yeah, these guys are punks.  It's very important you understand that that's how they're going to be represented. Now who looks better in that light? The guy who calls them punks aren't going to look very well at all if they're sitting there in coat and ties. They go to MIT and they've got professors backing them up. So that's one of the things you need to understand how you present your case to an attorney. One other aspect, I'm not your attorney. I do not provide you legal advice. So by all means, if you need an attorney, go talk to EFF. They do great work because at the end of the day it's very important. You need to understand something. Giving money and power to the government is kind of like giving whiskey and car keys to teenage boys. And so from that aspect, you need someone to keep that checks and balances that are going on there. And at the end of the day, if whatever the party may be, can't win that case, then they probably shouldn't have won that case. So they do great work and they're much needed. If you have a question, please feel free to ask it. I will try to answer it. If I mention your case, it's not on purpose. And if I forget to mention your case, sorry, get me afterwards and I'll work it in here. This area is huge. You could have a question that goes all over the place for internet and computer security law. Not everybody can know the answer. If I don't know the answer, give me your email address. I will research it and get back to you. My background, I was a legal advisor to the Army SIRT for several years. Jumped over, jumped ship, so to speak, and went and was the legal advisor to the Navy CIO. Stepped up, went and became the legal advisor for the US SIRT, left out of that office. So I'm no longer an attorney with the government and that's why I can stand here in a personal capacity, but I'm still somewhere in DHS. First case, I always like to come up with a case that's got some interesting facts, and this one really just jumped out June 30th. It deals with blogging, and the case is too much media versus hail. Sometimes the facts are more interesting than the case, but this one was dealing with anonymity and the right to actually blog, and it did present a case of first impression for this jurisdiction, and it's about posting defamatory comments on a blog or an internet message board and whether you could protect that information or who the source was to that. In this particular case, the blogger sued for defamation. She basically is a life manager, but the case deals with too much media and they have a software product called NATS, and NATS acts as a financial connection between two websites so money can go back and forth, and there was a vulnerability in it and she found out about this. Now, the defendant operates two websites and she kept a blog and she has a private investigators license. She's a respiratory therapist but no journalistic degrees and she's not employed by any news agency and never has been paid for any publication. Again, let's look at how judges are looking at these are the facts they take into consideration for where they're going. She has a website called Pornafia. Now, at some point during her business venture she became aware of cyber flashing. Apparently it's using webcams to expose yourself in a very quick method and that goes off. She got incensed by this and started investigating this. So she was going to launch this website and collect information. She never kind of got it off the ground, but she did join a couple porn web blogs to do research and she used a headshot of herself for her avatar or another one which showed the lower half of a naked woman with her wearing spiked high heels lying on her back with her legs partially spread.  I want to use the shield law from New Jersey which has apparently a very broad shield law so I don't have to reveal my source. These are the facts the judge is looking at. So she is saying that I have responsibility to inform the public on this. Now, the shield law protects people who are engaged or employed by the news media and they do keep that kind of broad for what a news agency must be. Newspapers, magazine, press, news agencies, wire service. So it's pretty broad but the judge keeps going through the case and he says, the rate the internet's grown, you've got several universal sources of news now but we can't sit here and expand it to everybody who's got a blog. I mean, it's a digital soapbox but we're not going to take this and move it that far. You've got a private investigators license, a degree in respiratory therapy. You're not connected with the news media at all. So having a self-titled web page does not make you basically part of the news media. So basically the court said, we're not going to let you use the shield law. You're going to have to take a deposition and you're going to have to basically tell all that's going on for that. So again, how courts look at the facts, if you're blogging out there and you're blogging as part of the computer security industry and you defame one of your colleagues, don't try to claim that you're part of the news media and informing the public because right now that's not working. Zango versus Kaspersky Lab. How many people have heard about this one? I kind of thought you would. This is an interesting case. Kaspersky was blocking through their product Zango's products coming out. It's interesting where you see where people fall down on this. EFF filed a Mika on this for Kaspersky. Interesting on that one because it blocks the Zango product. But again, it depends. Zango, during this case, one of the footnotes they drop in here is their FTC settlement that they had a while back, which means if you're going into this case and you've got an FTC settlement for deceptive practices for spyware, you're probably going to lose this one. And that's where it came down on this. They used the Good Samaritan Law under the CDA to say, no, no, no, you've got a lot of software vendors out there that can block malicious, spam, bad traffic, and we're going to allow that to happen. Especially they made a point that with all the companies that are going to be growing on this and the software products that are going to be going out there, we're going to allow this to stand. And so basically Kaspersky was on solid ground blocking the Zango spyware on this one. Those are two cases that recently came out. One of the cases I was waiting for for a long time was this Inray Boosher case. And it started coming across the border with the laptop, which is always a bad thing. And they were directed to a secondary inspection. They opened up the laptop and started looking at it. And they came across part that was encrypted. So they asked Mr. Boosher to come over and say, could you open this section up? Which he did. That's mistake number one, is volunteering to agree to do this. And while they do this, they saw some images they thought were child pornography. So they stopped doing their search at that time, shut it down, took the computer, got the warrant. And then when they went to reopen it up again, they found out that the hard drive or that part of the hard drive was encrypted by PGP and they couldn't open it up anymore. So they asked Boosher to provide the passphrase so they could get into the encrypted hard drive. Now I had a question a couple years back here about searching for different things. And someone asked if they're searching for a hard drive on my property and I haven't locked in a safe, do I have to open that up for the cops to get at? Now when you're searching something, you have to search those areas where it can reasonably be found. A hard drive is one of those things that's small enough that could be in a safe. And I said that's a very good question on that. Obviously if you're searching for a hard drive, you would have to open a safe. Now in the magistrate dismissed, he quashed the subpoena on the first case. And that's what we were waiting for. We were waiting for the appeal on this to come out because you knew the government was going to appeal it. And when it was quashed, that's what the judge seized on. And when the question was asked to me, I kind of missed a point on this, the question becomes, am I asking you to produce a key to the safe or am I asking you to produce the combination? And that's been one of the things that the magistrate looked at. If it's a combination that goes to your mind and that's a testimonial that he says, you know what the combination is in there, so you know what's in there. If I ask you to produce a key, which is just a physical aspect that exists, I'm really just saying, do you know a key exists? And yes, okay, that's not incriminatory. So give me the key and I'll go open it up and see what's in there. Now the magistrate kind of said the same thing on this too when he looked at it. When it got to the appellate court, they said, no, we're not asking for anything that the government doesn't already know is there. They saw two images on there that were child pornography. If there's more images on there, then are they asking for something that they already know is there, or are they not asking for something that's already there? It's an interesting question. On appeal, they said, no, no, they know it's there, so we want the unencrypted hard drive. They changed what they were asking for from the passphrase. So they know the grand jury said, now I want you to just give us the unencrypted hard drive. Like, that's a lot different than just getting the passphrase, because obviously to get the unencrypted hard drive, you have to know the passphrase. And so they said, you know the existence, the files are there, so you're not asking for anything new. And the other aspect is, by giving us this information, you can't authenticate that this is, these documents, or this hard drive unencrypted, is connected with you. And the government said, no, no, no, we will prove that by other evidence, so we won't use it for authentication, but we know the files are there. He already showed us and cooperated, so he should provide it. And they said, you're right. And so now the case is being appealed again by his counsel, who's doing a great job in this, and so now we have to wait to find out what the next court's going to rule on as far as whether this is going to stand or not. I don't know how this case is going to go. Both arguments are very good on this on both sides, so we're going to keep an eye on this in terms of providing a encrypted hard drive. I don't have this one in my slides. I apologize. It happened to do with a border search, and again, it dealt with a passphrase. This was an interesting case. A guy came across the border, they searched the computer, but when they turned it on, its pass were protected, so he logs in so they can see everything.  And so, you know, when you've got them in front of you, you're trying to figure out who's telling the truth or not, and he says, no, no, no, I didn't consent to giving them my passphrase. Cops saying, no, yeah, he did because he showed it to us. And so they looked at this from the aspect of the border search, and they said, well, it's a border search. We can do anything at the border. The government's interest, and this is the aspect, because border searches are really coming up. The government's interest in preventing the entry of unwanted people and effects is at its zenith at the international border. Time and time again we have stated, searches made at the border have that long right to the sovereignty being able to protect itself are reasonable simply by the virtue that they occur at the border. There's legislation pending right now to try to make it that you need a reasonable suspicion to search laptops at the border. The part on this is reasonable suspicion are non-routine searches. Just so you know, non-routine searches are body cavity searches, strip searches, X-rays of persons are all non-routine searches. I used to work at the counter drug command, and they used to do the X-rays of guys smuggling in drugs by swallowing them in balloons. So it's an interesting aspect on this. What is interesting, again, to give you how judges are thinking about this, the court is not persuaded by the defendant's contention that this is more intrusive. Incredible amounts of personal and sensitive information are already subject to scrutiny at ports of entries in people's wallets. Purses lock gloveboxes and lock containers and luggage. People carry personal items such as social security cards, state and federal identification medicine and medical records.  This is weird because I'm usually a, I had a lot of professors that said I've never seen a bad search, and usually I'm out there on that one, but I think this whole aspect of searching hard drives is a little bit different than peeking in my wallet, especially the amount of information that I can have on there. So that's how courts are looking at your border searches. So if you are traveling internationally and coming back in and bringing those things in, they are subject to search. The question is the aspect on the Boucher case, because there's an aspect on this on contempt proceedings. What if he forgets the password so he can't give it to it and he's frustrated?  That's the other aspect. This is the Webster Hubble thing with Clinton. This is where he wouldn't produce the records until he threw them in jail for a long time until he produced it. You know, that's the aspect, and that's the other part of this case.   And so that's an interesting point on that one. And the other aspect is, when I was looking at contempt of court, frustration is, hey, I forgot the password. I mean, let's be serious. You know, you get so many passwords, and we're told good security practice don't use the same password everywhere, use a different one everywhere else, and don't write it down. Judge, I was told don't use the same password, don't write it down. I got thousands of them. I forgot it. What can I do? And of course, he's going to escort me off to jail until I can remember on that. All right. So that's some bad things going on. Let's look at some fun cop cases. When cops don't have enough information to go get a search warrant, they will come and do what's called a knock and talk. This is very important for you guys because we're going to deal with scope of consent here, okay?  You know, it's amazing how much law we get coming from child porn. And they would come and they'd do a knock and talk. Now, when they're greeted at the door, obviously being cops, they don't say, you know, hi, Mr. Richardson, hi, Mr. Parsons. Hey, we're investigating child porn. Can we come in and talk to you?  They come up and they say, hey, now Richardson was interested. They came in and said, we've had some problems with credit card misappropriation going on on the internet. Can we come in and talk to you about that? Okay, mistake number one. Mr. Richardson says, sure, come on in. One other key point here. If a police officer ever comes up to you and says, hey, can I talk to you? Most of my friends who are defense lawyers say the answer to that question is no. It's not that hard. It's just just say no. This is a new mantra for you guys. Well, he comes on in and they sit down. And an interesting case, they're talking about this misuse of the credit card information and he volunteers that, well, when I was over in Germany and his wife's sitting there right next to him, we had a problem with child porn being on our computer from our credit card being used. We went and talked to the authorities over there and the FBI. Now he brings up the aspect of child pornography so we can see where the judges are going. That's not true. That's a red herring. Don't follow it. They keep talking to him about this misuse of the credit card. Keep going on that path. They'll say, can we, you know, image your hard drive and take a look at this? Mistake number two. Sure, go ahead.  Scope of consent.  I'm searching for a shotgun. Yes, that's where I can't go back and look in the safe that's this big unless it's a really small shotgun. But if it's not, if it's a normal sized shotgun, I can't open that safe because I have to look in places where it can be because that's the consent that you gave me to search for. And in this case, the court said, no, you came to search for evidence of credit card or misuse of credit cards, not child porn. That's so far of a ruse that's outside the normal scope of things. We're going to grant his motion and dismiss the case. It was an aspect where the ICE agents in Pennsylvania, both of these cases are out of Pennsylvania, got shot down. One of the next cases in the Parsons case, they want so far as to say, you're allowed to use ruses, you're allowed to fib a little bit, but it can't be a material misrepresentation that would actually overcome the voluntariness of the consent. It makes an involuntary consent by using so much of a lie. Mitchell. Mitchell was another ICE knock and talk case. And this is one that you can tuck away on an aspect if someone comes and knocks on your door and takes your stuff. The interesting aspect of this is they came, they did knock and talks.   And so, but they did, so ICE, the agents are getting better because they said, yeah, we are investigating child porn. Invites them in, says, yeah, they got them here. They imaged a hard drive and took that with them on it. Now here's the aspect. When you seize property, and again, this was a knock and talk, so they didn't have a warrant yet. It sat three weeks, and they didn't do anything to move it forward. If you come and you seize property, you have to within the Fourth Amendment make reasonable steps to search or secure a warrant to search that property. And it sat for three weeks, and they didn't do anything, and the guy went TDI, he went to a training course for two weeks, and they said, well, couldn't someone else have done it? No, I'm the guy that does it. I'm the only one. And the judge actually vacated the case saying, you didn't use any diligence whatsoever to move this thing forward. The fact that you went on a training thing for two weeks is no excuse for it. Now, they did specifically say, we are going to look at cases on a case-by-case, fact-specific case. So, if they come and seize your hard drives, and they don't do anything for 21 days, don't just start waiving this case, say, hey, y'all want it dismissed, come and give it back. And one other aspect I should point out, if cops show up at your door and knock and say, hi, we're here investigating child pornography, can we come in and search your computer? Now, this is something to tuck away.  I said, yeah, come on in, not a problem. They didn't say anything about seizing all my zero-day exploits that I've got sitting in my box. So, just tuck that away. Very good point, very good. All right, nighting. Oh, and one other aspect. So, if they come and knock on your door on this, don't start deleting evidence. Nighting, they came, knocked on his door and said, again, we're investigating child porn and he invites them in because can we see your computers? And so, he shows them two computers, one downstairs, one upstairs. So, he goes up to the upstairs computer with them, shows it to him, turns it on. It has an automatic program that will start washing and deleting cookies and files when he turns it on. Now, I think this is a slight miscarriage of justice because the guy's consenting, he is cooperating but the fact of the matter is he's coming up some of the evidence that was actually on one of the boxes. So, it's kind of like, you know, I always had my cops, they'd come and, you know, they'd say, we want to charge this guy with a resisting arrest and you're like, why? Well, when I went to arrest him and identify myself, he ran.  That's in your job description. You're supposed to go chase them. You know, there was only one time I actually didn't do that and that's when the cop was putting him in a new cop.  You know, great case, but you know, the cop never put a guy in the kid without putting that arm across the throat in the next time. But this one, what did you expect him to do? And the judge elevated his sentence two degrees because it was obstruction of justice because he turned the machine on, which the cops asked him to do, and started washing a lot of the evidence. So, again, interesting things, interesting facts. Meg Head, this is revoking consent. This is an interesting aspect and with computers, I've always been, I've been waiting for the case on this. The case that this falls under that they used for the precedent for this was a case where a taxpayer turned over his records to the IRS, consented to give them to him. The IRS made copies of the records and like a couple days later, the guy thought, wait a second, I just helped the case. I revoked my consent. I want my documents back. And so the court said, yeah, you've got to give him, he has an expectation of privacy, he consented to this. You've got to give him the documents back. Oh, but you don't have an expectation of privacy in the copy that you made. So we don't have to give you the copy back. And here the cops are investigating this guy for kind of terrorist things making bombs. So they had a search warrant and they got the consent to come in and search for everything that could be related to bond making, which using the computer to do information or do research is one of those things. The dad gave consent to this. This is a third party consent. Dad's got control over a common area. You can give consent when you've got control over a common area. They're the third party consent. We talk about it a lot. So they take the computer. Well, they make a copy of it. They image the hard drive. And dad and son come down there and say, we want to revoke consent. We want the property back. And so the judge said, okay, you can have the property back, but you don't have an expectation of privacy in the internet history files that have already been copied and they're searching them. Now, it's not quite clear from the case when that image of the hard drive was made or whether they started searching that image of the hard drive. That's about the only area that could give you some wiggle room and saying, okay, they made the copy, but they hadn't started searching it yet, so I revoked my consent so I want it back. Those facts haven't been presented, but it's something to kind of keep an eye on. Cotterman, this is the moving, I think, of a computer. Yeah. These are the border search cases again. And the interesting aspect about this is where can you do a border search? They came across the border, went to a secondary spot, based on some information that, you know, he had had a conviction years earlier. They start searching the computer or they want to search the computer, but of course the forensic stuff isn't there at the border. So what they do is they decide to take it from Tucson, which is 170 miles away, to search the computer. And there's a difference between where can I do the border search? Well, the functional equivalent of a border can be, you know, the ports and entry or your airports where you're coming in on international travel, but the judge said, you know, no, you needed to bring the equipment from Tucson down to here. I'm not going to move the functional equivalent of a border from here up to there to do the forensic search of it. The comments on this have been, if I take your computer and you're in the holding area, how do you know where I'm looking at it? You know, it's an interesting aspect of you mean tell me I've got to go get the forensics and bring it down here? I mean, typically it's not at the border in a border town. It's going to be up in Tucson in a bigger area or something like that. So there's a question on that aspect, but the judge here said, no, you need a reasonable suspicion, back to that reasonable suspicion, to move the border on that. This is going to be appealed, we think, and it'll be interesting to see. I would not be surprised if a judge said, no, this is reasonable under the border standard for you to do this.  One of the things that is in my neck of the woods and nape of the way has been this whole thing about cyber warfare. I didn't submit this year on this topic because I thought, eh, no big deal. And then in June, everybody in the world started, well, actually, thanks to July. Something early in July happened to some federal websites you may know about. And everyone started screaming, the sky's falling, the sky's falling. We're being attacked. This is one of the areas where I do get a pebble in my claw on what is an attack and what isn't an attack. To do, and cyber security, I hate the word cyber, to do computer network security and how the government does it, we're allowed, you know, to protect you'd want us to protect the network. This is a definition here in terms of what we are to protect. There's no words that say for the federal government, defend your network. There's FISMA, which gives each department an agency responsibility. DOD has a statute where they're told to do it. But for the federal government, it doesn't exist because multiple agencies and multiple authorities are used to do computer network security. For DHS, it falls on the Homeland Security Act. For each department agency under FISMA, they're supposed to defend their properties. And you see where the principal authority is for the Department of Homeland Security to do this. The debate becomes when, what you're dealing with. And this is where, as professionals out there, I would ask you to choose your words carefully. Again, being back to that lawyer thing about what word you choose, because when you have an event, that can determine who's supposed to be responding to this. And what I always used to get was when my guys would come running in and they'd say, hey, one of the sensors went off, we've got porn. And you're like, surprise, surprise. Now, I mean, it never fails. The guy in the military doing porn is like the general's aide. He's right next to the flagpole. And it's his computer. It is amazing how close to the top they're at. But it's always the aide. Go figure. Now, so when it hits, now I've got to pick up my phone and I've got to call cops, because I've got an incident where I've got basically cis admins and acceptable use policies and employers who are going to want to cover this. But I've got cops because I might have a crime. And so I pick up the phone to my cops and I say, hey, one of my sensors went off and it's porn. And they all say the exact same thing across the board. Is it child porn? I don't know. I didn't look at it.   And if it's not, then cops are gone. They're not even there. And so here's the thing. What could have been an investigation is now just an employer and a system administrator acceptable use policy violation of your policies. So each incident can be one of these things. It can be have law enforcement, intelligence. So who has primary jurisdiction over what's going on is very important, whether you've got an event, incident, intrusion, or attack. You know, these attacks that are going on, a couple years back a judge ordered the Department of Interior to disconnect from the internet because they were so hosed up and they had an Indian trust fund that they were responsible for and they were being sued and actually were told disconnect from the internet. If you're under attack and feeling so much pain, at what point are you under attack or I just have to disconnect from the internet and suffer a pain here so I can correct my own house? These are interesting things and interesting choices of words. This is one of the better law of law articles I've seen and this is the distinction which is important for the computer security field. Security, computer security for the government is done by the Department of Homeland Security. Defense is done by the Department of Defense. If you're under attack, you know, the Department of Defense and its mission is to fight and win the country's wars. Where does that fall in the cyber aspect of life?  That's where definitions come into play. Definitions are very important. When I first got into this business, I had two peers when I first got into this business. One who gave me a lot of great knowledge and another one who basically just tried to give me a headache as fast as possible. And he said, what's the law of the internet?  Now, being brand new and having thousands of acronyms, I had no idea what RFC was. I do know. And so I use this for my definitions from the RFC. But when you go into some other definitions, computer network attack, actions taken, disrupt, deny, degrade. Now, early in one of the talks, and I actually had to pull this out again because I like Scott Mutin, and Scott and I talked a while back. And if you want to know what's like to be sued and arrested, go talk to Scott. Scott got away with this. Well, it got away. At one of the EFF talks, they were talking about unauthorized access to cases and what qualifies for it. And in Scott's case, he was doing some security that he was supposed to be doing. And he was pinging a network to find out what the vulnerabilities were and what was open. And he's doing a ping flood on this one. Now, how Scott got away from this one when he got sued is the defendant agreed that the degration on their internet was minuscule. That's kind of changed a little bit. Scott said that any diminutive part that's going on there is going to be a degration of your services, so we're going to say that that's unauthorized access. Scott actually won because he said, well, there was no degrading of it because he was doing his ping flood here. He said there was no degrading, so we're going to dismiss the case, and Scott won this case on this. But he did end up getting arrested and having that fun stuff. So it's Scott Mutin versus VC3. It's not that hard to find on it. Well, is a denial service an attack? Well, if it's an attack, then computer security, homeland security is over. It's called DOD.   Can you help me? So you mean to tell me when you've got a denial service going on, you're going to pick up the phone and say, well, it looks like a cyber attack. Come take care of it. That's not actually the direction we go. And these things are being debated on who's supposed to be doing it and where. One of the aspects that I find going on now that I've also seen is this hyperbola of a cyber attack.  And you look at, let's see, what you guys are included in the conversation, organized crimes included in it, terrorists, and nation states. Then you look at who would want to do this. All right? Well, you guys could do it, and you may want to do it, but if you do, like all your colleagues are going to get really pissed because they're not going to have internet access anymore. And do you really want that unwanted attention for it? Well, we'll get it a little bit into responsible disclosure, but do you want that much attention? Organized crime. They're making money on this thing. It's just past the counter-drug trade as the most profitable business in the world. By the way, I used to work for DOD counter-drugs, and then I worked for DOD in Army Security, Computer Security. I think the problem might be me. So if I go work someplace else, find out what that is, because that might become profitable, might be the next step. So crime folks aren't going to do it. And so what you're really looking at is a nation state, but again, this thing is like nuclear weapons.  So you've got to use it sparingly when you're going to be doing that. This was an interesting article that came out talking about the 10 things you don't know about cyber warfare. The one, and there's been a huge, huge conversation between private sector and public sector saying, look, this hasn't been defined. We have not set up what the rules of engagement are. We want to be included when we set these things up. And I have to kind of back up and say, no, there's been a lot of research and things written on this. The nice aspect of this that I always liked was when private networks are hit, DOD will assume control. I'm sorry, but this goes back to the 1934 telecommunications law for basically when the president's going to invoke, things are so hosed up, he's got to take them on for a national vital interest. So the law goes way back there, and that's where it's going to go, but it's going to have to come from the top on down from that aspect. Back to my point of the fact that there's been a lot of legal research done on this, the use of force, different aspects on this. There's recently been blogs on it. Well, wait a second. If I'm a private company and I know this is going on, and I block that traffic, can I do it? And there's law of neutrality, law of neutrality for states. Once again, my first slide I said, Internet security law is all over the place. It's very wide. Well, yeah, so is this area, and there's a lot of research that basically hits all these areas when you're talking about it. So my point on this is, if you're calling it cyber warfare, if you think you're cyber warfare years or war years, DOD is cyber warriors, so I don't think you want to be grouped into that. I mean, so you guys go off and find the group you want to do for that, but that's the aspect on this, is who is in charge and who's doing what when you're getting to this level of an attack. Yes, sir? Yes, sir. We see as a U.S. cyber company, and the word cyber space, for better or worse, working its way through the nomenclature and maybe into the statues. My question is, it's being treated as a war-fighting domain. For better or worse, it's being treated as a war-fighting domain, and the Marines you call are going to say, this is a war-fighting domain. So my question is, it's this, why shouldn't the crime-fighting versus war-fighting puzzle that you're talking about be solved the same way as it is in land, air, space, sea, under space, and in planetary space. It's a war-fighting domain. I'm not presuming an answer, but I'm saying some Marine is going to say that to you. That's the question. Well, interesting aspect, and I heard it shout out over here, posse comitatis. When you go, let's see, well, you don't even hear that word in law school. When you go to the JAG school and become a young military lawyer, you go in and learn military law in a wonderful, I think mine was a 10-week course, fortunately they've expanded it more.  And when you get that guy to sit down, you say, no, posse comitatis. And it's using the military to do a law enforcement function. And as you're going through the JAG school for that first time, they tell you, don't worry about it. You're never going to use this. You're never going to have to be worried about it, because there's just very fine people, finite people who are going to have to deal with that. So on my second tour, I found myself at the counter-drug command, which I'm very proud of now at the JAG school, when they put up the two examples of violations of posse comitatis with a counter-drug command where I was at, and I actually got to investigate those things because we had some guys who thought they were cops and it went out a little too far. Balancing cybercrime, this is the aspect of what do you have? Event, incident, intrusion, or attack. Who has primary jurisdiction over this? Who's going to come in? And you know something, sometimes those even conflict where every time we had a hit where the cop said, it's a crime, I have jurisdiction, and you have the intelligence community saying, no, it's a foreign IP address. I have jurisdiction because it's foreign. And you got cops going, excuse me? Do you really think just because it's a foreign IP address that it didn't start here somewhere, which was the famous case where they thought it was in Israel and actually turned out to be in two teenage kids, I think it's in Montana if I remember correctly. And so from that aspect, getting all these people to work together in terms of what it is between being law enforcement, intelligence, or military is a challenging thing that we're working on right now. Yes, you have a cyber command being stood up under DOD. The aspect of that is to get things a little more organized from the military's point of view on that. Who gets primary jurisdiction on that? Again, it is very fact specific on what was hit, what was targeted, what was the effect, and what was the exploit. So there are some aspects of talking in those wonderful closed rooms to say, where do we think this is going to go and who has primary jurisdiction and who has an investigation opened up on it already. FDC versus Cyber Spy. This caught my eye for a reason going back to what was called the Sony case. When Sony first came out with their video recorders, they came out with a fine distinction to let these things go forward where if it's got a legitimate use, then we're going to let these things go forward and be products on this. On this one, you could argue they had spy, well, I'm sorry, that was the wrong word, remote spy, they had monitoring software that you could put on a computer to surreptitiously monitor the computer. And they got an injunction from the FDC to stop selling it because, well, basically they were marketing it from the aspect of, hey, get this and you can put it on a computer and no one will know it's there. Which is a little different than the way a lot of the other companies monitor their parental controls and the different products that are available for that.  You got to dismiss it and he denied it. So you've got the TRR going on. So we're keeping an eye on this litigation and it didn't help that these guys, again, were in front of the FDC earlier solving some of their problems that they had going on. I saw the 10 minutes, so I want to go through a couple things here. I think I'm into my, yeah, this is my cases and marriage cases. A lawyer's ex-wife installed, basically, a keystroke logger onto his computer, sending the virus there to do it. And the question becomes, is this a violation of the wiretap law or the Story Communications Act or Computer Fraud and Abuse Act? So this is very important. When you go and put your keystroke logging on someone else's machine so you can, you know, steal passwords and things like that, there's not a wiretap problem right here if it's not contemporaneous with the transmission of it. And that's the big thing for this aspect of it has to be contemporaneous and in transit while I'm stealing it. If it's just on the box and the computer there, they held that wasn't a violation of the wiretap act. The Computer Fraud and Abuse Act did survive and it did move forward on that. Other interesting aspects that we're seeing noted on this one are these cases that are not so much computer crime cases, but the research and the things that they're doing. Wendy May Davis basically killed her husband and she did some Google searches that might kind of give it away. One of the Google searches was decomposition of body in water. So they found that out and on that, Lee David Harbert, basically let's see, his searches were Autoglass Las Vegas, Auto Parts, Hit and Run, Reporting for Insurance Purposes. He did a Hit and Run, nailed somebody and killed them and by searching his computer and his Google searches they found him out. Justin Barber might be my favorite. His Google searches dealt with trauma cases, gunshot, right chest and Florida divorce.  An interesting aspect. Responsible disclosure is always an interesting aspect. I get an extra five minutes. Alright. I'm going to go... Ah, okay, no, I'm just kidding. I want to talk about responsible disclosure. I know EFF really hammers away on this and I just want to point it out from this aspect. They put up a slide they're saying about, you know, if you're getting into this, what are you getting involved in so you know it's tedious, it is grueling and nobody enjoys it. That's not really true. Attorneys live for this stuff. I mean, they're enjoying it. They're talking about my two attorneys in the town thing and again, when you're going to do this, you've got to think what your motive is for doing this. Now, again, my first rule, I hated the movie, what was it, did you say I can't remember it? Tom Cruise, A Few Good Men. I hated it when it first came out because I was a jag at the time.  And so we did the same thing in A Few Good Men. Except for one, well, then you find out there's several things that are really accurate. Like when he's telling the guy, look, it's two years, it's six months, it's a hockey season and you're out and I actually had to use that same thing on a guy who was accused of rape in Germany and he was going to go away for 25 years and I said, it's eight years. You'll see your daughter's third birthday and the one thing in that movie that's really accurate is when he goes in the courtroom and he's leaving and he goes, oh, so this is what a courtroom looks like? You know, that's true. You never want to see the inside of a courtroom. Never. So when you're going to do this and you've got a responsible disclosure aspect of life there, that's one of the things you've got to think about. What am I going to give up if I do this? I mean, you know, the case I got here, Dr. Munier Perdue, he taught computer science. One of his students reported a webflaw in one of the applications on the physics department. He reported it. Two months later, the place was hacked and cops came knocking on his door to say who was that student and he's sitting there thinking, I don't want to name who this was, responsible disclosure on this and so when he refused, the cops basically do what cops do. They started pushing him and you want me to get a court order? You want me to take you into court? You want me to get you arrested? So you've got to think when you get into this, what you're willing to give up and what you're willing to get in return and how important is this? I know Juniper pulled a presentation this year that dealt with ATMs from that aspect. We all know about Michael Lynn. You know, beforehand, Apple was getting nailed because they weren't fixing some problems with Java. So the aspect becomes why am I doing this? Why should I do it? There's different things for researchers and employees that you've heard. Employees, you do have an aspect where you could be revealing trade secrets or theft of trade secrets.  Researchers, depending how you're doing your work, you're going to be looking at the Digital Millennium Copyright Act, things of that nature. So I will agree with the first thing that they said, if you're in this line of work and you're doing this. The one thing I've always said in this field is that you need to take the technology and explain it to your attorney at a third grade level. Because he's going to take that and he's going to explain it to a judge or a jury at a first grade level. Now, it sounds silly. It gets a little laugh, but the aspect of this is it has got to be done and it has got to be done. It has got to be done. It has got to be done. It has got to be done. The aspect of this is it has got to be dumbed down so a judge or a jury can understand it. And that's why you've got to get your attorney involved early. Educate them. Tell them at the third grade level, but then educate them on what's going on, why it's important, why when I change that zero to a one, it changes from a normal honey pot to a fully operating honey pot. There are different aspects where I'm trapping everything. Where now I've got a wire tap issue going on, as opposed to maybe just, you know, capturing some information that's not in transit here and there. It's very important to be clear what you're telling your attorneys for that so they can tell people. Kalexy, they went over this. You got some last from this one. Kalexy was the case that they handled up in Boston where the kid had two operating systems and he was a hacker. So go figure. If you missed it, like I said, there's a first presentation on that one. A kid got complained on by his roommate and they went and seized all his equipment. Again, this is where bad facts end up with bad things. This is where the cops who actually executed the search warrant probably should be facing some liability on this one. Now you get the government immunity and good faith when you rely on a warrant, but when you're still outside the scope of what your employment should be, you can actually find, get personal liability. Now cops have, all the associations they belong to, they have insurance so when this happens to them, they have an attorney that is hired for them but the aspect on this is cops do face the liability if they act really outside the scope of the warrant. Side note, there's a great case that came out where cops were executing a warrant. It was like six months later. It had to do with a drug case and so they went to the address and in the warrant it specified they were looking for four African-American males, they kicked down the door, they go in and there's a couple in bed and they order them out of the bed with guns drawn and the guy says we can't, we're naked and the cops screams like a cop would do get out of bed and the wife and the guy get out of bed. They're not African-American, they're white and so they order them out of bed and the guy keeps pleading, can my wife at least get a robe and he says yeah, go get the robe so after keeping them there they finally let him get dressed and they go in there, they do the search and obviously what happens is four guys they were looking for had moved out four months earlier, I mean the warrant was that stale on it and of course these two people turn around and sue the cops and the cops won. It was a good faith basis that they had on a warrant they went in there, it doesn't necessarily when you're dealing with drug cases mean that you're going to find anything, something dangerous could have been under the bed so when you're talking about getting outside that cop aspect of things it does get a little hard to get out of there. One thing to point away on this this is Goumen versus Klein. This was a very litigious case it had been in five years earlier that had been some orders of preservation of evidence and finally when the defendant I'm sorry, when the plaintiff got the defendant's laptop he thought it had been tampered with and they hired a court forensics expert to look at it and he came in and said yeah judge, basically point blank this thing not only were files deleted but they actually went back in and then changed the time stamps on it to say when the files were actually there or deleted and it was a pretty, pretty harsh case and the judge has to figure out what to do when you're spoiling evidence and there's sanction so you can give to the attorneys, you can get attorney fees, things of that this was so bad the judge actually gave them a default judgment meaning when the plaintiff came in and said I'm suing him for whatever dollars the judge says yeah, you're entitled to it it was that bad of a case again, aspects of where forensics are coming in very important computer fraud abuse act, cases have been used to basically say when you're leaving a company and you take information from the computers you've exceeded your access and your authority based on an agency law relationship we're seeing basically the case is suing the other way, we're court just saying you know something, sum under an agency theory we're not going to let you use the computer fraud and abuse act for this anymore independent news goes back to the blogging aspect if you're a blogger, kind of try this one is in the materials on the CD that I gave you there it gives you the five things to look for to determine if you're going to get protection or not in a defamation case or if they're going to let somebody who's got a screen name actually find out who the heck you are behind that screen name contact information if you have any questions please feel free to contact me you know it's a DHC don't hack it that's why I didn't give you mine so by all means I hope you enjoyed it if you have any questions we're going to 104 I guess on that thank you very much


Hi all, now what I'm going to be doing is using JMRI's panel pro is install a small section of mainline track with a couple of turnouts and a passing solid in and running through how we actually get that onto our panel pro panel. So to start off with what we need to do is install our turnouts. So we start off by moving up to the top left hand side of the screen clicking on turn out and we'll click on the right hand turn out first placing the cursor onto the left hand side of the screen holding down the shift key on the keyboard and then left clicking on the mouse and this installs the right hand turn out in our screen. Next what we need to do is install a left hand turn out on the opposite side so that we come back up to the top of the left hand side the screen click on left hand turn out holding down the shift key again doing a left click on the mouse. You'll notice that the left hand turn out is a orientated the wrong way so what we do is do a right click on the circle here in the turn out scroll down to rotate and we enter with a rotation angle of 180 degrees click okay and then that orientates the turn out around the right way so we'll just move this out to the right a little bit move anything that we've placed on the screen it's just a matter of holding the cursor over the object then doing a right hand click holding the right mouse key down and then we can move that around. Then what we're going to move on to is installing our first section of track in between our two turnouts so you'll see the anchor points on the turnouts here are red at the moment so then what we need to do is install a track segment so we move up to the left hand side click on track segment want to be picking main line so ensure that's ticked and then moving to the right hand turn out moving through the straight section of the turn out holding down the shift key left clicking on the square and then dragging the cursor across to the other turn out and then letting the mouse key go and you'll see that we install that first section of mainline track you can see that it's worked by the anchor points in our green on both sides now what we want to do is we want to install some mainline track here this side of both sets of turnouts and what we'll do is say that we can install two blocks on the approach to each of the turnouts we're going to install two separate blocks at the side so to do this what we need to do is install anchor points so we click on anchor point at the top left here again holding down the shift key left mouse click there's one two three and then four and now what we can do is install our mainline track between each of these anchor points so back up to track segment ensuring mainline's ticked shift key left mouse click to the first anchor point shift key again and then back to here you'll notice that whenever the track's been installed correctly we'll get these green anchor points now again moving over to the other side shift and left mouse key click and again you can see now that we have our two sections of track or two blocks either side of the turn out now what we want to do is we want to install our small passing siding so what we can do here is we just add another couple of anchor points just get the passing siding a little bit further away from the mainline track click back on track segment now what we want to do is unclick mainline and this will install the passing siding and see how the lines are a lot thinner than the mainline track and this will indicate that the track's actually a passing siding what we can now do is we can alter the angles of these by doing a right mouse click and then dragging these tracks out a little bit and we can therefore drag the distance out and change the angle of the track until we just get the geometry right and now you have it now we have our section of mainline track on the top here with two blocks approaching the turn out block in between and our small section of passing siding on the south side of the mainline so in our next video we'll be going through how to install the sensors for each of these sections of track


Let us now start with the description of the dynamic programming algorithm. So what one does in a dynamic programming algorithm is one does the following. So I will explain the dynamic programming algorithm in the form of a proposition and we will then do the proof of the proposition as well. So the proposition is as follows. For every initial state for every initial state x0 the optimal cost remember we had denoted this by j star of x0 is given by last step of the following algorithm. So the last step of the following algorithm what is the algorithm? This is actually the dynamic programming algorithm. What one does in this algorithm is the following. So one proceeds backwards in time. So you define jn of xn in the following way you define jn of xn as simply the terminal cost which is we define jn of xn as gn of xn and this is so for we write this for all xn. So we want to write this as a remember we need to write this as a function. So jn of xn is declared to be identically equal to gn of xn. So for all values of xn then for any then as I said we will proceed backwards in time. So this is at time n. Now what we will do is write this for times k less than n. So at any other time k before that we write jk of xk as we write this to be equal to the minimum over all uk where uk belongs to has to be in the actions that you can take at time k. So uk belongs to capital UK of xk and we take now the expectation. So the minimization is of this expression the expression that I am about to write now. This expression is the expectation of the stage wise cost at time k plus the this function jk plus 1 that you evaluated jk plus 1 evaluated at fk of xk uk wk. Now recall again that fk here this here was my dynamics recall that okay recall let me write this let me write this here recall that the dynamics was given in this form f of xk plus 1 is equal to fk of xk uk wk okay. So we want this. So here is the expression. So here is the algorithm at time n when we declare jn of xn to be equal to gn of xn for all xn. At all other times k we write jk of xk to be equal to this and this again is for all xk and this is also for all times. So all k from 0 to n minus 1 okay. So we so this therefore tell this algorithm basically as such to the following it says we you take the you write j you declare you find or define these functions you define these functions jn jn jn minus 1 jn minus 2 and so on for all for so in other words jk for all k from 0 to n jn is defined as equal to gn of xn that is what was given to us it is the terminal cos jk of xk for k less than n is defined recursively it is defined in terms of jk plus 1 that that we have. So the way this would work is that you have jn already written up through that is through the through the through the terminal cos then you write using that you find jn minus 1 using this because in that you would have jn here out here then you write jn minus 2 using the jn minus 1 then you find the jn minus 3 using the jn minus 2 and so on. This would eventually get us to j j 0 for every initial state. So that would this would eventually give us j 0 right j 0 of the at every initial state. So this would land up at land us up with j 0 of x 0 and what the proposition here basically tells us that is essentially saying that j star of x 0 is is nothing but j 0 of x 0. So it is the last step of this particular algorithm. So you do you apply this algorithm backwards in time starting from time n and at when at time at time 0 you evaluate this at x 0 and that tells us what the optimal cost is starting from time time 0. Now there is also a second part to the to the proposition which I will write that out here. The proposition also says that if u star k equals mu k star of x k minimizes the RHS above. So what is the above expression? It is this expression which minimizes this RHS for each x k and k then the policy pi star which is given by mu 0 star to mu n minus 1 star is optimal. So now let us reflect on this a bit.  So I just said that j k is defined recursively in terms of j k plus 1 but how exactly is it defined? So it is defined by do you what you do is you do a minimization with respect to the action u k at time k. So when we are computing when we want to compute the left hand side here j k of x k or when we want to compute this right hand side here we are fixing an x k we are fixing x k to be any token state. We let x k be any any state at time k for any such state we compute this expectation and minimize it over all u k that are that can be chosen in that state x k.  This minimization will give us a u k star. This minimization gives us a u k star which is the optimal action but that u k star would be different for could be potentially different for different x k that u k star is going to be a function of x k because in this minimization problem that we have here x k is a parameter.  Now it is and let us denote that function as mu k star. So this minimization defines for us a function that maps x k to an optimal action and what is such a function? Well that is that function is a decision rule it is a Markov decision rule it is mapping the state at that time to an action. So what this theorem is also telling us is that you put together all these Markov decision rules which is mu 0 star to mu n minus 1 star put that then gives us a Markov policy and this policy is actually an optimal policy for the for our problem. So here is therefore the summary for every initial state x 0 you if you want to find the optimal cost is what you do is you solve you do go through this recursive algorithm and at each step in the recursive algorithm you what you do is you minimize this particular expression this cost if you recall the so what is this cost this cost is the stage wise cost plus the cost to go the cost to go evaluated at the next the cost to go is evaluated at the next state the next state is written out as a using this function which is using the dynamics. So the next state is expressed using the dynamics as a function of the current state the action and the noise right and then so then one minimizes this so you take the expectation with respect to the noise. So this expectation here is with respect to the noise w k and one minimizes this expression over u k you minimize this over u k you get u k as a function of x k let us denote that function as mu k star and you and you do this over for every for every k going from k equal to 0 to k to k equal to n minus 1 till k equal to 0 and the claim is that well you are the optimal cost at x 0 is simply given by this function j 0 of x 0. So it is the it is given by the last step of this particular algorithm. Now let us so let us dwell on this dwell on the efficiency of this particular algorithm as to why this is actually helping us save some effort. If you see the initially when I when I mentioned that we you know if you look at the problem of choosing the optimal policy over the set of all Markov policies the set of Markov policies turned out to be a humongous number turned out to be a raise to b raise to b raise to n right where a was the number of actions b was the number of states and n was the number of precision epochs or the time horizon this was the number of policies. So if you if you had to search over all of these policies this is the number of choices that you would have to cycle through. Now let us see how many how many choices do we need to cycle through when we have when we are doing this when we have to apply the dynamic programming algorithm. So what one does here is suppose once again we have we have a actions and b states right. So this optimization is a choice over a actions that is the number of actions that we have. So there are a choices here. So one has to basically compare a numbers. So there are by that can be done by computing all all a of them and finding the least. So you so this so this for every every value of the state xk can requires a a computations. So if there are a actions this would require at most this can be accomplished by by doing a computations at most. Now and this has to be done but this has to be done for each state for each value of xk. Now xk itself can take b possible values since xk itself can take b possible values this this computation has to therefore be done for for b such values of xk. So you need to repeat a calculations for b values. So therefore the number of computations you need to do is at most b times a. So and this is the number of computations one needs to do for each stage. And now this has to be done for each k since remember this we have to do this for k equal to 0 to n minus 1 which means that we need to do b times a calculations at each stage. So that and there are n stages. So there will be the total number of computations that we need total number of computations becomes roughly a times b times n times some constants. I am ignoring all these all the trailing constants here. But this tells you what the total number of computations is roughly going to scale like. So it scales like and it scales as the number of actions times the number of states times the number of stages. If you compare this with the complexity of listing out all possible policies the problem of listing out all possible policies was basically involved as doing these many listing out these many possible choices a raise to b times n. Obviously this is a dramatic reduction no question about that it is very evident that we have truly simplified the problem by doing this. So how has this simplification come about? This simplification has come about by exploiting the additive structure of the cost function that the problem our problem definition involved a cost that was defined stage wise. This additive structure gave us a recursive way of computing the optimal policy which is what is given in terms of the dynamic programming algorithm that what this is also done effectively. Another thing that you need to note that has happened in this is if you recall that I mentioned at the start of the course that any stochastic decision problem although it involves finding optimal actions which is finding vectors the stochastic decision problem by its very nature forces us to think in terms of not actions but in terms of strategies or policies. And therefore the problem any non-trivial stochastic decision problem basically becomes a problem of finding the optimal function over a set of functions. Indeed our policy set like pi md, pi hd etc these are also sets of functions and when I when we do calculations such as a raise to bn this is also the set of the number of functions that we have from a set of from a set of size b to a set of size a. So it is really a so the problem that we had defined was really a problem had was essentially a problem of finding an optimal function over a set of functions. So that is what the stochastic problem basically reduced to. Now because this these things because the problem is that of finding an optimal function one could the first instinct is to ask how many set of functions and try to solve the problem in the space of functions itself. But then that is that what we realize here that that is not the best way of approaching this problem because there is more structure to this problem that we can exploit. And as a result of this structure we get the dynamic programming algorithm and if you see what is happening in each step of the dynamic programming algorithm is that we are not really finding functions at all. We are not finding many functions at all we are really find what we are not optimizing over the set of functions all optimizations that happen in the dynamic programming algorithm are vector optimizations we are finding optimal actions not optimal functions. Of course we are doing this for every x but that is still that implicitly defines for us a function that is that is true but that is still far less complexity than searching over the functions directly. So what this is effectively done is reduce the search of reduce what was what was essentially a search over functions to search over the values that the function can take which is which is the UK's essentially and through the values you end up defining the function. This is this is this is a this is an extremely important and dramatic reduction. As we will see later in this course that there are this sort of reduction is something that we would all like we would like to aim for in every possible problem however there are significant limitations that come up later when we look at the information structures and so on. But nonetheless this is a this is this is a victory to saver because we have we have been able to we have been able to bring down the complexity quite significantly. So let us quickly run through the proof of this of this particular proposition. So it is the proof will use basically the idea of induction. So I will write out the proof here. So let pi be a policy be a be a policy and let pi k pi superscript k denote the truncated version of this policy. So you look at the policy from mu k to mu n minus 1 this be the truncated one. Now let denote j star k of x k not j k remember j star k let this be the optimal cost of the n minus k stage problem. So the problem that starts from stage k and ends at time n. So j star k is basically the minimum over all policies all these truncated policies the expectation of the terminal cost plus plus these stage wise cost starting from k up until n minus 1. So this is j star k. Now what we will and and similarly let j star n also so we want this of course for all x k let j star n also be defined as g n of x n and this also is true for all x n. Now what we will do is we will argue we will show j star k of x k is actually equal to j k of x k where what is j k well j k is are the set of are the sequence of functions that are that are coming from our algorithm it is these functions j k are these functions. The functions that come from the algorithm are j k what we will show is that these functions are nothing but the optimal cost the optimal cost of the n minus 1 n minus k stage problem. And so we will argue this by induction we show this by induction to show this by induction. So suppose so we already know this for n it holds for n. So for k equal to n we already have that j star n of x n is equal to j n of x n and these are both equal to impact g n of x n. So for k equal to n this holds the induction hypothesis holds.  Now notice that we can write pi k the the truncated policy pi k as in this in the following way we can write it as mu k the decision rule at time k and the truncated policy from k plus 1 onwards the truncated policy pi k pi k pi k plus 1. So notice this. Now if we if we notice this then we can write j star of j star k of x k this can be written as minimum the minimization over mu k comma pi k plus 1 of r expression which was g n of x n plus summation i. So in fact I let me I can write this much more. So we can we can write j star of x k in in the following compact way we can write this as we pull out the stage wise cost here we have also the terminal cost g n of x n and we have then the remaining stuff the remaining stuff which is going from i equal to k plus 1 till n minus 1 g i of x i u i w i. So now we are minimizing this over mu k and pi k plus 1 but then notice that mu k is mu k actually comes up only here. So what are we doing here well your u k is in fact mu k of x k and u i is mu i of x i. So in other words your mu k out of these mu k and pi k plus 1 the mu k only appears here the the ones that appear here are all the mu i is from for i equal to k plus 1 till n minus 1. So they they are the all the later the later mu's are the ones that appear here. So as a result of this I can actually write this in the following way I can take the pi k plus 1 inside. So I write this as minimization over mu k I have the my expectation g g k of x k mu k of x k w k plus minimization of over pi k plus 1 of the expectation of g n of x n plus this summation which is which is which is i from k plus 1 till n minus 1 g i of x i mu i of x i w i. And well what is this particular expression well this expression is is this expression here is simply the optimal cost j star k plus 1 starting from the state starting from the state x k plus 1 that will result from the quality from from from the state x k and the state and the action mu k of x k. So in other words this here I can write as I have j star k plus 1 of f k of x k mu k of x k comma w k. But then by induction hypothesis we we had assumed that this j star is in fact equal to j k we had assumed that j star k is in fact equal j star k plus 1 is equal to j j k plus 1. So this j so this j star can be removed I can in fact I can erase the star here and the expression is still valid. So this is still equal to so this is therefore this equality still holds. But then now I I can after having removed the star what I am left with is this right hand side and this right hand side is nothing is nothing but by by the dynamic programming algorithm this right hand side is nothing this it is actually this quantity. So this is the same as the right hand side of this dynamic programming algorithm and that is nothing but j k itself right. So this quantity therefore is equal to j k of x k. So in other words by the induction hypothesis the induction hypothesis holds for k equal to n and then it holds we have assumed it holds for some k in between and then from there we conclude that it holds for for any for the next k as well and then and by hence it holds for all k for so in other words we have for all k j k of x k is identically equal to j star k of x k and this therefore completes the proof because now for I just apply this for k equal to 0 and x k equal to x 0 and then that tells me that the dynamic programming algorithm has actually produced for me the optimal the produced for me the correct cause. One can go through this argument further and also show that very easily that the policy that comes out of this that means the optimal mu that comes out of this is in fact also an optimal policy. This is a quick proof of of the dynamic programming algorithm. In the next class what we will do is we will apply the dynamic programming algorithm to an actual problem of inventory control.


Today was another session, public session, of the January 6th committee hearings. They met today, focused primarily on, you know, Trump trying to induce Pence to desertify, to refuse to certify the votes that were coming in, the constitutionalality of that, who influenced Trump to do that, the response of Pence, all of that was kind of discussed today. And, you know, again, I don't think there was much new other than the extent to which this was corrupt, the extent to which the people advising Trump knew that what they were advising him was probably illegal. And here you primarily, what's his name? Eastman. I mean, he was so convinced of what was advising Trump was illegal that he actually asked that Trump pardon him before he'd ever been accused of a crime, pardon him in advance for the advice he gave him, because he was afraid that one day he would have to be in court trying to defend something that he knew was illegal. Now, I know John Eastman. I've met John Eastman, I've had conversations with John Eastman. I think John Eastman, yeah, maybe introduced me before a talk that I gave. He was, he was the Dean of the Law School at Chapman University for a few years. So I met John Eastman. I was very shocked that John Eastman was involved in what, with Trump, involved with Trump in the way that he was, that he gave Trump the kind of advice that he gave him, that he supported Trump's attempt to steal the election, that all of that happened, very disappointed in Eastman. I thought he was a better guy than that. But it turns out that he was giving this advice. He knew it was wrong. He kind of, you know, Trump's going to be Trump and I'm going to tell him what he wants to hear. I know it's illegal. I want to get pardoned. Please pardon me. Please, please pardon me. So I don't have to ever face the music for what I just did. It's going to be interesting to see what happens because when he was actually asked questions by the committee about issues relating to January 6 and about his advice to Trump and about what everything else was going on, he played the fifth to everything. He basically played the fifth, I think, 100 times. So he gave no answers. So it's going to be interesting if ever there's a case brought against him what it actually does. But look, Trump tried to illegally, illegally in null and election and take over the American government. I mean, he basically tried for coup. He didn't get away with it because Pence didn't go along, because the military probably wouldn't have gone along, because he probably couldn't have gone away with it. But he did what he could to try to get away with it. This is the guy so many of you admire. He wanted to basically wipe out a legal election. And everybody in his administration was telling him, other than Giuliani and a few other kooks, everybody in his administration was telling him, and this is what we've seen time and time again, is you lost. You just did. You lost. There's no basis for overturning this election. None, zero, null. None, nada. Be a man. Recognize this. And not only did Trump continue with the lie, try to put pressure on his vice president, and was conceiving all kinds of ways to use the National Guard to seize ballot boxes and machines and do a whole variety of illegal things. From the perspective of the Republican Party, he got away with it. The Republican Party has basically said, yeah, we're fine with that. We have no problem with it. Trump's a good guy. We're all behind Trump. Even though the guy's the first guy in American history, as far as I know, that actually tried to illegally overturn an election, seize control illegally of the US government. I don't think that's ever been tried. And the Republican Party is like, cool. We're with you. It doesn't matter. You're still the best guy possible. Now, that is insane. Now, just take the fact that during, you know, people are writing at the Capitol, they're breaking windows, they're using violence, they're rampaging through people's offices. Pence and certain congressmen are calling Trump and saying, we feel like we're in danger. This is a real danger. Something really bad here was happening. And Trump does nothing. He doesn't call the National Guard. I mean, he's the commander in chief. There's an insurrection, and he does nothing. He just sits there, watches television. And it's only Pence who calls up the National Guard, which is in and of itself illegal. It's just mind boggling.  We'll vote for him again. How? How is that possible? How is that possible?  He makes Richard Nixon look like, like the most honest guy ever. I mean, he is a thousand times worse than Richard Nixon. And I was glad to see Michael Lidwig, no, not Lidwig, Lutig, Michael Lutig, L-U-T-T-I-G. He's a former pellet judge, a staunch Republican, a staunch conservative. I'd probably disagree with him about issues all over the place because he's such a conservative. On the short list of denominations of Supreme Court a number of times, including I think on Trump's short list, he came out with a statement lambasting Trump today, lambasting Trump today. But more importantly, lambasting the Republican Party.  I'm not going to read it to you, but you know, those who think that because America's a republic, theft and corruption of our national elections and a electoral process are not theft and corruption of our democracy are solely mistaken. America's both a republican and representative democracy and therefore a sustained attack on our national elections is an attack on our democracy, our political theory, otherwise notwithstanding. Accordingly, if and when one of our national elections is actually stolen from us, our democracy will have been stolen from us. To steal an election in the United States of America is to steal her democracy. And in a sense that he means democracy, I agree with him completely. Whoops, what did I do there? It is breathtaking that these arguments, the arguments about, you know, overturning the elections, that these arguments were even conceived, let alone entertained by the president of the United States at that perilous moment in our history. Had the vice president of the United States obeyed the president of the United States, America would immediately have been plunged into what have been, what would have been tantamount to a revolution within a paralyzing constitutional crisis. The former president's accountability under the law for the riot in the United States Capitol on January 6 is incidental to his responsibility and accountability for his attempt to steal the 2020 presidential election from the American people and thereby steal America's democracy from America herself. This set willful ignorance of the law and the fact is neither excuse nor defense in law willful ignorance less as neither political nor legal excuse or defense available to the president of the United States as allies and his supporters. On January 6, 2021, revolutionaries, not patriots assaulted America. The walls of all three of our institutions of democracy were scaled and breached on that appalling date. And almost two years hence, one of America's two political parties, he's a Republican member, one of America's two political parties cannot even agree whether that day was good or bad, right or wrong, worse. It cannot agree over whether January 6 was indeed or not needed or not. Pause for a moment and reflect on that. The former president and his party cannot decide whether the revolt at the United States Capitol to disrupt and prevent the constitutional counting of votes for the presidency was needed. And therefore, whether another vote might be needed at a future date to accomplish that which the previous revolt failed to accomplish. The former president's party cynically and embarrassingly rationalizes January 6 as having means something between hallowed, legitimate public discourse and a visitor's tour of the Capitol that got out of hand. January 6, of course, was neither and the former president and his party know that it was not legitimate public discourse by any definition, nor was it a civics tour of the Capitol building. Though that day proved to be an eye-opening civics lesson for all Americans, I wish, I wish. January 6 was rather a defining and a redefining day in American history. Defining and redefining of America itself.  So bloodshilling was that day for our democracy that America could not believe her eyes and she turned them away in both fear and shame. Even so, many have already forgotten and many more have chosen to forget. Some who rioted and occupied the Capitol that day had already decided how this war for our democracy must end. While others of the account compatriots upon sober reflection afterwards decided that no, this war must end now before there's further bloodshed. And he goes on, it's a pretty long statement. But he says, America is a perilous crossroads. Who is it that we have become and what is it that America has become? Is this who we want to be and what we want America to be? And if not, just who is it that Americans want to be and just what it is that America wants to be? Not always well-written. Let's see if there's some. Now what he really is afraid of, what he points out here, is that Trump and his supporters are basically set up to 2024 elections for them to steal. No matter whether, if he loses 2024, he's now got people in position in various parts of administrations at the state level who can not certify the elections, reverse them, send different people to the Constitution Convention, constitutional convention to the Electoral College, sorry, to Electoral College. And he is terrified that in 2024, Trump will steal an election. He tried to steal the previous election, failed. And now he's going to try to steal this election. And he's right to be terrified. If you watch and you see the kind of people being elected by Republicans or some of these primaries, it is truly scary. It is truly scary. So it's going to be interesting. There are going to be more revelations that make a big deal now of the role of Judge Thomas' wife in the proceedings. I've met her too. I've heard her speak. I've met her. She is not. I don't like her at all, never have. I like Thomas. I like many of his rulings. I do not like his wife. She was a horrible, populist, Republican way back. But it is interesting to see what her role will be in this. Hopefully Thomas had no involvement and it was not kind of guiding things in the background or whatever because I'd hate for him to leave the court. But yeah, I don't like the wife. I don't like Judge Thomas' wife. So it's going to be interesting. I think this is crucially important that the Republican party, not the American people, the Republican party comes to terms with January 6th. And I don't think they are. And I think as long as they don't, it's basically a disgrace. It's basically a disgrace. Ian says Ted Cruz cloaked for Lutig. That's interesting. That's interesting. Maybe Lutig can give Ted Cruz a call and give him a chewing out over this issue because Ted Cruz is one of the bad guys here. The Republican party better wake up before they are responsible for the end of freedom, political freedom in this country. Thank you for listening or watching The Iran Book Show. If you'd like to support the show, we make it as easy as possible for you to trade with me. You get value from listening. You get value from watching. Show your appreciation. You can do that by going to iranbookshow.com slash support by going to Patreon, subscribe star locals and just making a appropriate contribution on any one of those, any one of those channels. Also, if you'd like to see The Iran Book Show grow, please consider sharing our content. And of course, subscribe, press that little bell button right down there on YouTube, so that you get an announcement when we go live. And for those of you who are already subscribers and those of you who are already supporters of the show, thank you. I very much appreciate it.


Richard Branson was born on July 18, 1950, in Blackheath, London. Richard struggled with dyslexia from childhood and had to struggle with educational institutions. So, he was academically poor. Having no interest in studies but desiring to become an entrepreneur at a young age, Richard eventually dropped out of school at age 16. After he concluded a school was not where he wanted to be. On his last day at school, Richard was told by his headmaster, Robert Dresden, that he, Richard, would either end up in prison or become a millionaire. What a frustrating farewell statement. Richard attempted to grow and sell both Christmas trees and Bodgerigas in England, but he failed. Instead, he launched a youth culture magazine named Student in 1966, though the first issue was published later due to some frustrating factors. The first 50,000 copies of his magazine were disseminated for free, but subsequent copies of the first issue earned him almost $8,000. Richard gradually rose to success as his net worth rose to about 50,000 pounds in 1967. In 1969, Richard found himself within a community surrounded by the drug scene and British music. This influenced Richard into launching his Mill Order Record business in Oxford Street, London, England. He intended to use the fund from the business to promote his magazine efforts. Richard interviewed some famous personalities of the late 1960s and advertised popular records in his magazine. This brought Richard an overnight success. However, Richard was arrested in 1971 and charged for selling records in his store that had already been declared export stock. And it was so early in his business days there was no way Richard could repay the debts and the charges led to his mother having to remulgage the family home. When Richard was in his late 20s, he got stuck in Puerto Rico, trying to get a flight to the British Virgin Islands to visit his then-girlfriend as the flight was cancelled last minute due to lack of passengers. Richard was desperate to travel and his last chance was to chatter a plane but he had no money on him. An idea came to him. He picked up a small blackboard and wrote Virgin Airlines. $39 one way to be the eye on it. He sold the tickets to the people who wanted to go to the Virgin Islands. Not only did he get the money to pay for the chattered plane but that was also the birth of his Virgin Airlines and the rest is history. Today, Sir Richard has an estimated net worth of $4.1 billion. For young Richard Bratzin, dyslexia was a big obstacle and he could have ended his life struggling to fit into the academic world as having a degree is a God in our present world. Many of life struggles is as a result of fish trying to fly. As Albert Einstein allegedly said, everybody is a genius.  Most of us can do great stuff with our lives but if we are operating in a world where our strengths cannot shine, we're fish trying to fly. So the first step toward overcoming life's obstacles is to know who you are and where you belong. Another big lesson we can all learn from Richard Bratzin is that life isn't straight. Even if you're a bird, flying would still not be easy at first. You'll have to train your feathers, try flying and fall many times. This is because every great thing takes time. Just as Warren Buffett said, you can tap a baby next month by impregnating nine women today. While some of us need to stop trying to swim as fish, others just need to learn how to patiently endure the pains that come with learning how to swim. Richard Bratzin decided to quit school because he could never be a great student. You have to know where you belong and choose your fight according to your strengths. Bratzin went through several failures trying to build a business. Most times, all you have to do to overcome obstacles is to hang in there. Just as Roy T. Benek said, your hardest times often lead to the greatest moments of your life. Keep going. Tough situations build strong people in the end. If you like this video, do subscribe to this channel so you'll be notified when we publish our next videos. Also, like this video or share it with your friends on social media. Thank you. We love you.