So, welcome everybody to session 1 of day 6, there are two talks today in the morning, the first is by me and the second is on database security by professor Sudarshan that is the talk that begins at 11.30. So, let us now talk about protocol vulnerabilities. So, this is hardcore network security and we also have two demos associated with this presentation. The first is on Nmap and the second is on Nessus. So, we need to understand what are the vulnerabilities in different networking protocols. So, this is a little different from the vulnerabilities in the protocols we had discussed earlier. So, if you recall we had various security protocols. So, another word for security protocols are cryptographic protocols things like SSL, IPsec, Kerberos, Needham Schroeder, the various authentication protocols for wireless communications in cell phones and wireless LANs etcetera. So, those were really cryptographic protocols and there were various vulnerabilities in those protocols such as the replay attack or the parallel session attack or the man in the middle attack and so on and so forth. Today's session is a little bit different it is on regular protocols that you are very well familiar with TCP, IP, ARP, DNS etcetera etcetera. So, almost all of these protocols has some vulnerability or the other it does not appear to be a vulnerability, but if you look close and hard you will find it and the goal is to try and see how we can exploit it and later on in tomorrow's session how we can defend against some of those attacks. So, let us get back to the slides. So, this is an important saying over here once we know our weaknesses they cease to do us any harm. So, we should know the vulnerabilities in these networking protocols both in the design of the protocol as well as in the implementation of the protocol. So, let us look at some of these vulnerabilities. As I mentioned there are vulnerabilities almost across the spectrum the 7 layer stack starting from ethernet 802.11 and ARP, IP and ICMP, TCP, UDP, DNS etcetera etcetera. One point is the vulnerability may be in the protocol itself it may be in the implementation of the protocol. So, the software that implements the protocol might for example, have a buffer overflow vulnerability. One of the most well known such attacks is the denial of service attack and there are various manifestations of it. One set of denial of service attacks is due to certain attributes of various protocols and another application based denial of service attacks. So, here we are going to focus on protocol based denial of service attacks and various protocols might actually be the cause of this. For one thing the TCP protocol may be exploited to create what is called a sin flooding attack or you might have exploitation of the UDP protocol for UDP based denial of service or even an ICMP based denial of service. So, we will look briefly at some of these. So, first a sin flood an attacker sends thousands of TCP packets to the victim with a sin flood a sin flag set. So, the intention appears to be to establish a connection. So, to establish a connection as we all know in TCP because TCP is connection oriented there is a three way handshake. So, the first packet is a packet with a sin flag set, the second packet is from the recipient to the initiator with the sin and act flag set and the third packet is just with the act flag set. So, an attacker sends thousands of TCP packets to the victim with a sin flag set. The victim innocently thinks that these are legitimate requests for TCP connection establishment that is to say the first message in the TCP three way handshake. Now, in response to each message the victim reserves buffer space eventually the victim's communication link and or memory are exhausted or perhaps even the computational capability. So, the victim are seriously crippled because of the flood of sin packets. So, to review this is the three way handshake the initiator and the responder. The first packet is the sin is with the sin flag set there are six TCP flags sin fin reset etcetera. The first one has the sin flag set and it has some value in the sequence number field some random value it is supposed to be random random value set in this set in the sequence field. So, let us say that value is x what is the responder do he sends a response message with the sin flag set and the act flag set. He acknowledges the receipt of this packet by setting the acknowledgement field. So, there is an acknowledgement flag and there is an acknowledgement field. So, that acknowledgement field is set to be x plus 1. So, x plus 1 is over here and then he also randomly sends one value y. So, both these values x and y are random and the actual random number generator is decided by the operating system. So, this is an operating system a dependent implementation issue what are those random values x and y. And then the initiator response with the third message saying I have received your acknowledgement and now let us start to talk let us start to send and exchange data. So, it sends the third message now only with the act flag set the first one was only the sin flag set the second one was both sin and act flag set. And the third one is only the act flag set and the value in the acknowledgement field will be y plus 1. So, I have received your message with sequence number y and now I am acknowledging it and saying that I am ready to receive y plus 1. So, this is a very standard three way handshake which most of you are familiar with in a computer networks course. Now, let us see what opportunities exist for attacking or exploiting some of these. So, one possibility is the attacker sits down over here the victim is over here there is a single attacker single victim he sends one sin packet. So, these are called sin packets the first packet in the three way handshake he sends one sin packet he keeps bombarding the victim with sin packet after sin packet. And the victim does not know what is going on he thinks these are legitimate requests for connection and to each one he responds with a sin plus act flag set. Now, the only thing is not to be discovered what he does is he spoof the source IP address. So, instead of his own IP address he put some other fraudulent IP address and as a result these packets go off in a different direction the packets the second packet in the three way handshake for each of these request packets the response packet does not go back to him, but goes back to the supposed source of this packet with the somebody else all together. So, it goes in a different direction he does not really receive it and he does it. So, that he is not able to be detected. So, one feature of the sin flood attacks and indeed dose attacks in general is you are trying to hide the identity of the sender by spoofing the source IP address. So, besides exploiting TCP you can also exploit UDP and attacker sends a large number of UDP packets to non-listening ports on the victim. So, the goal is to slow down the victim. So, what you do is you try to waste his time doing what send him UDP packets to non-listening ports. So, what does he do this causes the victim to respond with an ICMP message stating host unreachable for each of those packets each of those UDP packets that it receives it responds with an ICMP host unreachable message and that of course, wastes CPU time. So, that is about UDP and then we can also exploit ICMP through a well known attack called the smurf attack. An attacker sends a very large number of ICMP echo request messages to the victim's network. Now, what is interesting about this is that the destination IP address of all these packets is the special broadcast address. So, he sends just one packet the attacker sends just one packet with the destination IP address as the special broadcast address. So, this packet receives is received by all of them because it is broadcast everybody on this network and he spoofed the source address he makes it appear that the victim has sent this when actually he is sending it. So, the source IP address is the address of the victim. So, what happens is everybody thinks the victim is saying echo request and everybody responds to this victim and as a result the victim has to process each of those packets the victim is slowed down. So, this causes the victim to be inundated with echo reply messages from each host on the network. So, this is another example of a denial of service attack where it is not very serious perhaps, but at least you slow down the victim because of receiving so many packets being able being and the necessity of processing all these packets and then responding to them. Now, let us make a denial of service attack a little bit more sophisticated using what is called a distributed denial of service attack. So, what exactly happens in this case there is the attacker as you can see out here and he actually compromises several hosts as you can see.  And then each of these hosts does a similar kind of thing he compromises a whole bunch of what are called zombies. So, once again he sends the infection transmits the infection like it is done in the case of code read for example, through a standard payload and each of these is infected and is commanded basically to do what he wants. And what is the command the command is to attack one of these victims.  So, this is this has the feature of being distributed. So, distributed denial of service attack. So, some features of DOS and DDoS. So, sin flooding it is an example of a DOS attack caused by a vulnerability in the TCP possible abuse of the 3 TCP 3 way handshake. So, some features of these attacks very often you will find that the source IP address almost always the source IP address is typically spoofed. There are multiple attack sources especially in the case of a distributed denial of service attack. So, multiple attack sources the victim reserves buffer space for each connection request. So, you have to reserve some amount of memory to accept packets from the source and it might lead to memory and bandwidth exhaustion, but also computational power might be consumed unnecessarily. So, there is a possibility of memory exhaustion of bandwidth saturation of computational degradation in processing because you are spending so much time in processing those fake requests. So, these are some of the features of DOS and distributed DOS. Now, we would like to come up with a simple model to see how serious this problem is. So, that we can take remedial measures via some sort of an intrusion detection system. So, we look at these various parameters to model the effect of this attack. So, one is the communication bandwidth of the victims link. So, let L be the communication bandwidth of the victims link. Let B be the maximum number of buffers reserved for TCP connections and let T be the maximum amount of time that the buffer can be reserved for a half open TCP connection. So, we actually describe what these things mean the maximum amount of time to be reserved for a half open TCP connection. And some more parameters these are attack related parameters R is the aggregate rate at which the victim receives sin attack packets from the various sources and P is the sin attack packet size in bits. Now, the question is what harm can this cause and we can be quantified through a very simple model. So, we can use more complicated models, but I am trying to come up with a very simple model to find out when memory can be exhausted or when the link can get saturated. So, what are the conditions for each of those? So, for that purpose let us write down some of the this notation from the two slides and then we will try to write down two equations which can capture memory exhaustion and bandwidth saturation. So, these are some of the parameters we are trying to model the effect of DDoS on the victim. So, once again L is the communication bandwidth in bits per second B is the maximum number of buffers utilized by TCP. So, do not forget that TCP is implemented as part of the operating system T is the maximum amount of time a buffer may be reserved for a half open TCP connection. So, let us try to clarify what this thing means in a second R is the aggregate rate at which the victim receives sin attack packets from not just one zombie, but from all the all the zombies that are attacking it and P is the sin attack packet size. So, let me clarify what is meant by the maximum amount of time that a buffer may be reserved for a half open TCP connection. So, the attacker sends the sin packet the victim responds with the sin plus act. So, this is the attacker this is the victim now this victim is waiting for the third packet of the handshake. So, it hopes to get it sometime by say this point in time. So, this is the time line it hopes to get it by sometime over here it waits it waits it waits patiently does not get it what does it do it times out and resends the sin packet sin plus act packet. So, this is resending it. So, resending the second packet in the three way handshake and it waits again patiently to receive this thing waits and waits does not receive it again it waits for some more amount of time before it resends. Now, this amount of time that you wait before resending and the number of resends both of these are operating system dependent. So, these depend on the implementation of the OS. So, all of this time before it just simply gives up. So, it will resend may be three times and then it will give up. So, all of this time between receiving the first sin packet and waiting and waiting and waiting until you give up this is the time that we refer to as t in this. So, now with this notation we would like to find out two things what is the expression what is the condition for bandwidth saturation or link saturation and then what is the condition for memory exhaustion. So, first link saturation. So, that should be pretty straight forward it is related to which of the three things it is related to the rate of attack packets it is related to the packet size and it is related to the link bandwidth. So, the rate of packets multiplied by the packet size is greater than what the communication link can hold then the link saturates. So, rate of packets multiplied by packet size and bits if that is greater than or equal to the link bandwidth then of course, the link can no longer hold anything and basically they can be no communication supported anymore and that is exactly what the attacker would like for the link to saturate. So, that is the condition for link saturation let me write it down again clearly r times p greater than l the link bandwidth what about memory exhaustion. So, this should be somehow related to the rate of packets that time t that we just described and the number of buffers that the operating system reserves for TCP. So, the rate of packets multiplied by the amount of time that is that the packet that a buffer can be held if this product is greater than or equal to the number of buffers then memory is exhausted. So, now we have no more memory to support TCP and either the operating system tries to get some more memory or there is a great slow down in the receipt of packets. So, either of these cases seems to satisfy the attacker. So, he is hoping that the bandwidth the link might saturate he is hoping that memory will be exhausted and of course, the third thing is computation. The victim is spending a lot of time in processing these useless packets and the CPU will slow down greatly. So, all of these are the effects of a DDoS attack and we will see later on tomorrow how we can do two things number one is how can we detect this and how can we try to prevent it. So, these are not foolproof methods, but at least we can try and once again the distinction between detection and prevention. So, before I continue there is one little thing I would like to say and that is how did we get this particular thing. This is an example of what is called little's law in networking and it is a very useful law that is used again and again in different contexts. So, I will just briefly illustrate this thing. So, in a typical network you might have. So, think of this is one of the switches you have got several buffers in these switches. So, think of a router or a switch over here. So, these are different input buffers. So, packets are coming in and packets are going out you might have input switching you might have output switching you can have shared memory switches and all kinds of different switch designs and then this is connected to some other switch here etcetera. Now, the neat thing about little's law is you can draw a boundary anywhere. So, you can draw a boundary around one switch you can draw a boundary around a single buffer you can draw a boundary across multiple switches and in either case ask yourself the question what is the average number of packets. So, suppose I draw a boundary across these switches ask yourself the question what is the average number of packets in this subsystem what is the average number of packets inside the subsystem and that is related to the arrival rate into the subsystem let us call that lambda. So, the arrival is from various sources if you consider the boundary like this. So, look at all these fluxes the rates into the system from different directions these inputs. So, this rate we are talking about and multiplied by the average time that a packet spends inside the subsystem. So, the average rate of packets into the system multiplied by the average time it spends into the system is equal to the average number of packets inside the system if in any point in time I just look and ask how many packets are there. So, there are two packets in this buffer there is one in this there are three in this and so on and so forth and I look at there is one that is getting ready to go out and so on I just look at the average number in the system at any point in time. So, I do this experiment again and again and again I look at the average number I look at the average aggregate rate into the system from all these different sources and an average time that a packet spends in the system then I have a very interesting relationship between these three things that the average number in the system is equal to the average rate into the system multiplied by the average time each of those elements of packets spends in the system and this is independent of the statistics of the arrival rate the arrival rate could be points on it could be anything else and still this relationship holds. So, this is the relationship I have used in deriving the little expression for memory exhaustion. So, once again link saturation when the rate of attack packets multiplied by the packet size is greater than the capacity of the link l and memory exhaustion when the rate of attack packets multiplied by the time for reserving the half open connection I explain what is that capital time it includes everything from the receipt of the first sin packet to the time when the victim gives up after having resend the message several times he gives up he is not received the third message of the handshake he keeps trying again and again until that time we refer to that as t that interval is referred to as t. So, r times t is greater than or equal to the number of buffers reserved for the TCP protocol. So, now that we have talked about the attack and the effect of the attack just a little bit about actually we will talk about this in great detail tomorrow during the session on IDS, but what are the possible mechanisms what can you do to handle a DOS and DDoS. So, you could have prevention mechanisms detection you can do neither and just respond to the attack. So, you are not proactive over here, but you are reactive you respond to the attack and then you let the attack happen let the effects of the attack happen and then say I am going to figure out who was responsible for the attack get to that person and possibly throw him in jail. So, you want to trace back find out who is responsible who is behind this attack. So, we look at different strategies for prevention detection response and trace back. So, we look at that in the context of IDS tomorrow we continue with the different kinds of network security protocols that could be attack we have looked at ICMP, UDP, TCP and now ARP. So, the next thing is ARP spoofing. So, you might have seen this some of you might have actually experimented with certain tools to do ARP spoofing one of the well known tools is cane enable for example. So, the first thing about this aspects of this attack it exploits certain features in the address resolution protocol it results it could result an ARP cash poisoning and in MIM attacks. So, that stands for man in the middle attacks session hijacking and so on. So, these could be very dangerous attacks where an adversary on the local area network that you belong to is actually trying to hack in and look at all the messages that you are sending may be even change them in a standard man in the middle attack. So, what is this most of you have already seen it. So, we just recap very briefly what is ARP it is used to resolve an IP address to a MAC address. So, we had just briefly talked about DNS where you resolve a domain name to an IP address. Now, you go one step further and you resolve an IP address to a MAC address. So, I have the IP address of a certain party and I am trying to find out what is that person's MAC address. If a station A needs to send a packet to B it is not sufficient that A knows B's IP address A should also know B's MAC address. For this purpose what is typically done as part of the ARP protocol is ARP broadcasts on the local area network and ARP query containing B's IP address. A station that has or knows B's MAC address responds directly to A. So, the first thing is a broadcast and then it is the direct communication to A whoever is knows the answer to that will respond to A. Now, the only thing is there will be multiple guys who know the answer to that question what is B's IP address and multiple guys might respond and then again it depends on how this ARP is implemented ARP might just look at the first response and neglect all the other responses. So, the IP address MAC address translations are cached. So, I often need to talk to somebody and I need to two different people actually and I have the IP addresses and I want to know the MAC addresses where do I look. So, typically I look into a fast memory and as everybody knows fast memories are called caches. So, I look into the specific ARP cache to quickly obtain the parties MAC address. So, these translations are typically cached ARP cache entries have a lifetime because they might change you might change the IP address views DHCP and so on. So, the IP address could change and as a result ARP cache entries should have a finite lifetime stations periodically send out ARP requests to update their cache entries. So, what is the current MAC address of somebody and so on any node X may send an unsolicited reply. So, these caches need to be updated now some guys might try to be extra helpful and what they might do is for example, node X may send an unsolicited reply to a node A regarding the MAC address of an arbitrary node B. So, I never asked you what is B's MAC address still X will send to A a message saying that B's MAC address is so and so. These are called unsolicited replies I never asked you for B's address, but you simply send it to me. So, this feature ARP referred to as Grotutus ARP is a serious vulnerability. So, there are actually two different things over here number one is when A requested for B's MAC address as I said before many guys might respond to A saying this is B's MAC address. In particular the attacker might also respond and he might try to be very fast. So, B itself might respond. So, once again the question is A is asking what is B's MAC address and there could be several guys who are responding one of the guys responding could be B, but you could have responses from others as well. So, what might happen is A might just take the first response and ignore all the other responses. In particular X may also respond and X may respond fast. So, this is not unsolicited this was solicited A actually asked what is B's address MAC address and every many guys responded including X and X happens to be the first. So, X's response will actually be cached the other situation is where it is unsolicited. Nobody asked for B's MAC address, but the attacker X actually sends a message to A saying that B's MAC address is so and so once again the MAC address is a 48 bit string as you all know. So, now let us see how this particular feature gratuitous replies and unsolicited replies might actually be exploited to launch some kind of a man in the middle attack. So, I will just show in a picture. So, here you have a LAN and you have three entities of relevance there is an A guy a B guy. So, these are innocent victims sort of and then there is an attacker X. So, how does this attack actually proceed. So, the first thing is a gratuitous or unsolicited response from X. So, message number one a gratuitous response from X unsolicited saying that B's MAC address is little x. So, to clarify this notation the IP address of this guy is capital A and the MAC address is little a. The IP address of this entity is capital X and the MAC address is little x and the IP address of this entity is capital B and his MAC address is little b. So, the attack starts with an unsolicited response from X saying that even though A never asked for it he sends it unsolicited response saying that B's MAC address is his own MAC address just imagine. So, this is a lie that B's MAC address B's MAC address is actually this thing little b where he says it is little x and he very humbly and meekly accepts this and he updates his ARP cash. Now, the second message he does the same thing to the other victim B. He says that A's MAC address he is telling B that A's MAC address is little x. So, once again B updates its ARP cash. Now, a few minutes later they want to communicate with each other who wants to communicate with whom A wants to communicate with B and B wants to communicate with A and in general they would get the messages directly through the LAN. A would talk to B and B would talk to A without any interference from the attacker, but because their caches have been spoofed what happens is when A is trying to contact B this is the message it sends to B this is the data part this hashed thing over here is the data part and this is the header and as you can see the source IP address is A. So, A is sending the message and he wants to talk to B that is B's IP address and he wants to know what is a B's MAC address and because his cash has been poisoned thanks to this message he puts B's MAC address as x and as a result the LAN will actually the LAN switch or the LAN hub will actually route this thing to x. So, x receives this message what does he do he can read this he can change it etcetera assuming it is not encrypted he can read it change it etcetera. So, that is message number 3 which is intercepted in a sense by x a man in the middle thing and then message 3 prime. So, he receives it reads it possibly modify something over there and then does a little bit of work he changes something in those fields. Now, he changes the MAC address back to little B so that we can receive it the original packet had little x he has changed it to little b and. So, the LAN routes it to B. So, B has seen the message for the message from A as pass through x and possibly been modified by x and exactly the same thing for response from B. So, he sends a message with the source equal to B that is himself and the destination equal to A that is this guy and the MAC address equal to x because his cash is also been poisoned. So, the MAC address is little x that is intercepted by this guy it is actually routed through him he reads all this stuff possibly modifies it changes the MAC address back to little a and then ships it out. So, you can see this is a standard man in the middle attack cause due to some problem with the ARP protocol the ARP cash has been poisoned and as you can see the vulnerability is also that you have messages that are not authenticated over here. So, that is one of the vulnerabilities you have these gratuitous unsolicited messages floating around. So, what could be the possible solutions one thing is this allow gratuitous ARP responses another thing is. So, one of the features that caused all this in the first place were these unsolicited responses and so on that is not the end of the story though that is only one scenario the other thing is allow only authenticated ARP replies. So, this might require support of PKI or some kind of Kerberos system then do not allow caches to change value of course, that is not very practical use ARP caches that are static which ignore updates sent by random machines. And then finally, there are switches built today that can handle this problem intelligent switches which learn which MAC addresses and IP addresses are mapped to which switch port. So, you find some strange thing coming in from a certain port I never see this port containing MAC address little b, but today I find it I get suspicious or I do not find little x today I find little x as the MAC address I get suspicious and I handle that packet I probably destroy that packet. So, use intelligent switches which learn which MAC address MACs maps to which port and which IP address maps to which port. Also monitor IP address MAC address pairings and ethernet frames and an ARP replies and check for any inconsistency with what has been learned by the switch. So, for example, I might get suspicious if I see a mapping like this destination IP address b and MAC destination equal to little x I have been I have been used to thinking of little b of capital B and little b over here suddenly I find b and x I get suspicious and I try to handle it by probably destroying the packet of something. So, these are some of the possible solutions you can ask yourself what are the pros and cons of these different solutions how easy is it to be to implement it how effective is the solution etcetera how cost effective is it and so on. There are also attacks on DNS they follow along exactly the same lines just like you have an ARP cache you also have a DNS cache and the cache can be poisoned due to unsolicited responses and so on and so forth. So, I will skip these you can just read them there are any questions do get back to us. There is also solution to this DNS set that is implemented on many different routers and many different systems which use DNS. So, those that is one possible solution to DNS cache poisoning and all the DNS attacks and then finally, before we start with the demos I will just mention briefly about vulnerabilities in LANs. LANs are probably the easiest thing to exploit and the reason for that is there are very standard protocols it is a common access medium. There are standard protocols that depend on the good behavior of all the entities on that LAN if some of them decide to misbehave the entire operation of the LAN can get crippled. So, an ethernet and 802.11 LANs for example, there are very well defined rules governing when a node should talk how long he should talk for how many nodes should handle how nodes should handle collisions etcetera etcetera. You very well know in CSMA CD for example, if there is a collision or even an 802.11 when there is a collision what exactly should I do should I back off for how long should I back off etcetera etcetera. The smooth functioning of these networks depends on the stations on the LAN strictly obeying the MAC rules otherwise in the worst possible case you could have one particular guy who jams the entire network. So, nobody else can talk nobody else can understand what is happening on the network. So, such problems are serious problems if some of these guys misbehave. So, there could be several attacks due to vulnerabilities in the MAC protocol which can be exploited by these bad guys. There are rules governing when a node may transmit after sensing a collision or rules related to inter frame spacing for example, in the case of 802.11 if these rules are violated stations on the LAN or the wireless LAN will see garbled messages. Frames may also be spoofed. So, there are several attacks there are several tools that do this you can ask your students to look at those tools and implement it if you have got a wireless LAN on your campus. Frames may be spoofed leading for example, to premature disconnection of a communicating party of two communicating parties. For example, a party has set up a connection with access point and suddenly that connection can be terminated because of an illegal the authentication frame or disassociation frame which has been spoofed by the attacker. There are several such attacks which are mentioned in section 17.4 of the text. So, with that brief introduction to various vulnerabilities in normal protocol these are not cryptographic protocol just your normal protocol and how these could be exploited. We will now turn to two particular demos one is on N map. So, the basic goal over here is to find out. So, this is in preparation for an attack what should I do I should try to find out on this particular network which are the hosts that exist which hosts are alive and once I found that out which ports are open on those hosts and then once I found out which ports are open whether they can be attacked whether any vulnerabilities behind the application or the service on that particular port. So, there is a sequence of these demos which we will do partly in the we will actually do in the lectures and the those demos will also be repeated in the lab. So, those demos are a full sequence of them today we will do Nessus and N map and tomorrow we will continue with Metasploit and Snot and the same thing will also be done in the lab tomorrow Thursday during the lab session.


Blockchain technology has gained significant attention due to its potential applications in various fields such as data management, finance, cybersecurity, internet of things, IoT, healthcare, and brain research. It has been used to improve the safety and reliability of healthcare data sharing and can potentially revolutionize the way healthcare is delivered by providing personalized, authentic, and secure care. This paper reviews the current state of blockchain technology in healthcare and discusses its applications, challenges, and future prospects. This article was authored by Assad Ali Seel, Ayesha Zahid Jani Ho, Mohammed Zahish, and others.


Hello, my 15 amazing speakers for Derritable 2023. It's me, Chris. Thank you all for being here. I am so excited to be sending you this update. We are less than 30 days, about 29, 28 days out from the event as of today, April 19th, 2023. We are reaching almost 100 people now, speakers and attendees. So we are right at the numbers we wanted to be. I'm super excited. I just sent out an email and a video yesterday. So you should have been on that list to kind of get an update on all the surprises. But I wanted to make a really quick video just to you guys, the speakers, to kind of get your heads around preparing and being ready for the conference. I know that some of you have expressed to me this is your first time speaking or you have spoken before but you're a little bit nervous and there's a lot of reasons to be nervous. I speak all the time, all over the world. I'm really fortunate to do it. But I thought out what I wanted to do was give you some practical tips and tricks on how I have used my experience as a speaker doing this conference for the last three years and working with other speakers to help make you more successful. To get this started, I wanted to go over a few kind of housekeeping things with you and then get right into thinking about your presentations. So the first thing is we are 30 days out or less than 30 days out. So by now you've hopefully made your travel arrangements. You're flying in, driving in. We have people coming in from all over the world to San Francisco. I realize some of you have mentioned the cost of housing. Yes, it is expensive. It's expensive anywhere you go. Just try going on vacation. So do what you can to find the appropriate Airbnb. I know one person found a hostel. I'm staying at Airbnb. I know some people have actually collaborated and gotten places together to make yourself comfortable. San Francisco is super safe. Contrary to what you may read. And we're right on Market Street. So there's a lot of places I know I looked right around there when I was looking for places to stay and travel. I actually will be coming in a week early. So I'll be there, not a full week. I'll be coming in Sunday for our conference that's on Wednesday and Thursday. And I'll be staying until Saturday. So if you come in early and you wanna come see the space, I'm planning up being at air table on Tuesday the 16th. So reach out to me and I will make sure I get you in to see where you are going to be speaking. Next time, more time, it's always about time. Your session, if you're doing a regular session at their table 2023 is one hour and 15 minutes. Now that might seem relentlessly long or not long enough depending on where your mind is in this presentation. But I'm gonna tell you this right now, it won't be enough time.  It'll only seem like a long amount of time until you actually get there and then it'll be fine. If you're speaking at a keynote, there's a few of you, I know those people I've spoke to you. Your time is still a bit shorter. It's only 45 minutes. So a few things about the time, how to break it down in a little bit, but just to kind of get your heads around it, you're aiming to be in a room with your class for about one hour and 15 minutes if you're in a session or 45 minutes if you're in a keynote. Now don't worry about filling all that content. Like I said, at the end of this video, I'll give you some tips and tricks to make that space expand or contract depending on how you're feeling about the time. Our space is at Eric Table headquarters and we're on the top floor. So they've got two floors, we're on the top floor. It's a massive space. It's got a main center space where Airtable actually has their hands meetings and then some breakout spaces, which means you could be in one of three different spaces when it's to your time to talk. Two breakout rooms and the main room. Now obviously the main room sits everybody and the breakout rooms cannot fit everybody because they're breakout rooms. So what happens is we will invite people to pick their sessions before the event or they can make up their minds at the event. What's great about this is what we found in the past historically is people will go to an event or a session they really like and we try to put the sessions we think are gonna be the most full in the main area based on a few things. People have signed up already, interest. If it's hands on, it's better to be in a breakout, one of the breakout areas because they have tables. If it's not hands on, a more kind of thinking main room. So don't be overwhelmed. Your space has been already selected. So if you go to the website and look up the event calendar or the agenda or if you're logged into the portal and look at this, you'll see which room it is in at the bottom of your session. Don't be overwhelmed if something has to change. Last year we found a lot of people went to one session and not so many went to another and we had to switch the rooms. Not a big deal, it happens all the time. You never really know where people's minds are so don't overthink. If you've got more people than you wanted or less people than you wanted, everything will be fine. If you wanna film your session for posterity, you're more than welcome to. We had someone last year who brought a GoPro and filmed their whole session and they actually use it as a meteor roll now so feel free to do that. As far as other things, lunch will be in the main area along with all of our sponsors both days. We'll be doing tours for everyone at the lunchtime midway point, two o'clock both days. And as speakers and additionally getting paid, you're all getting special gifts and swag from Airtable. So lots of surprises coming for you speakers. If you've spoken at Airtable in the past, you already know that we tried to treat you guys as good as possible. Finally, arrival. When you come, you can come when the regular conference starts. You don't have to worry about being there extra early or extra late. I'll show you two of your room. Each of the rooms will have a screen that you can plug into with your laptop. We'll have the HDMI cables and other type of cables or AirPlay, whatever we need. Airtable has a great IT staff I've been told that will be on hand for you to go ahead and plug in and get everything you want ready. Should you have any problems? Again, we'll have someone there to help you out. Don't overthink it. Again, I know you're overthinking, it's okay. We'll take care of you, we've got you covered. Now the presentation itself. Woo, this is the big star, right? This is where it gets serious. So when I speak, I like to do presentations that are mapped out in my mind first. And I always think about what am I trying to get across? If you remember when each of you submitted your presentations and I wrote back to you, I said, what are the three or four points that someone will take away? Those are really your guiding principles. You could almost make a bullet list where you have your points and then work up to those. Always try to make the overall theme or goal of your presentation be aligned to the title and subtitle. And the rest will just fill itself out. After I do a mind map, if you haven't done a mind map or a bulleted list, try it out. The next thing you want to do is to remember to always come back to your takeaway. So I like to do a mind map, and then each of those little lines have kind of the takeaways and then build slides backward to that. So think about your building a movie and you know the ending, but you have to fill in the rest of the story now. And that's kind of the best way to think about your presentations. One of the best tips I ever got on speaking is nobody cares what you know. They care how you thought about it. So what does that mean? Well, I could list and I'm gonna show you how to do this air table formula, or I'm gonna show you how to put together this interface and kind of drag this here. Again, that's what I know. People find presentations engaging that tell you how you thought about it. So I'll give you an example. I'm teaching, so the example of what I know. So I know that when I'm building a presentation, interface designer interface, it's best to have a logical flow. So at the top it starts here and then I have a middle ground and then I have an ending and in between I have maybe call outs and bullet points. That's, I know that, you guys know that when you hear it. And so does the audience. And if you tell people something they already know that you know, they kind of get bored. But if you tell them how you think about it, interest, interest, interest. For example, same scenario, interface designer. When I'm building an interface designer, I think about myself, I'm probably gonna be bored halfway filling out this form. I need something. You know, I get bored when I fill out forms.  I sometimes even use animated pictures again because it draws my eyes to it. And people want their eyes to be drawn to things. That's not what I know, it's how I think. Those two scenarios should really help you understand how best to think about your presentations as you're getting ready. Let me give you an example of that. So when I was preparing my slides for last year, these are them, I've got them up on the screen now. I started out with the name of the session. And then I went through with right away in the beginning, the goal. So you can see right here, the goal was to inspire people to think differently about data. So in this presentation, no matter what I did, I knew that I couldn't go wrong because it's pretty easy to think differently about data after explaining how I think about data, right? The other thing is I made sure I used lots and lots of pictures. So people love to be visually stimulated, right? So when they think about things, they want something that's not thought provoking, but also visually stimulating. So when I'm telling them when I think about time data, I could show them a picture of a calendar or I could show them how my mind sees a calendar. Does this make sense the way I'm thinking? So again, in this slide I had, I didn't wanna tell them about thinking about how a calendar works. I wanted to think about how a calendar stores information as far as I'm concerned about how I think about it. So this is a really good example of that. Next thing, you might wanna actually, once you get through your ideas, you might actually wanna talk about Airtable. It's an Airtable conference. So there's a couple of ways you could do that. You could show screenshots of your Airtable base. Again, screenshots are always great. I love screenshots. Or one of the things I did last year to make things easy was instead of screenshots, I intermixed animated GIFs. Now GIFs are really interesting because what they do is they bring a sense of motion to your slide. If you've never used a GIF and you're on Mac, there's a tool I use called CleanShotX that will literally record the screen but make it a GIF. It's super, super simple and easy to use. I always frame my GIFs inside of devices because a lot of times people wanna see those ideas inside the machines that they actually are gonna be running on. And sometimes I'll take still pictures and GIFs. So in this case, I've got three different device types, three different types of images moving and not moving. The idea is to create something inviting that people wanna come to. Got it? Good. Next, don't be afraid to do hands-on. Even if you didn't tell me you're gonna do a hands-on. People like to play around and explore things. So in your session, if there's a place for a hands-on, allow people to do it. If some people didn't bring laptops, that's fine. Invite them to participate while other people are doing hands-on by talking, which brings me to my last point, participation. Don't save all your Q and A for the end. You can, but it's sometimes people are just like, okay, I can't remember my question that long. Break it up. Do one QA at 10 minutes, one QA at 30 minutes, another one at one hour. And just break it up and tell people, you didn't put it right in your slides. We're gonna have a Q and A time right now. Don't be afraid if you say, does anyone have any questions? And there's no questions. Say, does anybody have any answers and allow the audience to add to your presentation, right? The idea is by inviting people to make you successful, everyone is successful. All right. So hopefully that'll give you some great tips on thinking about your slides and getting ready for the event. Always at the end of your slides, add a slide where people can reach out to you. If you wanna add a site that people can download your slides, that's always a great thing. I use QR codes, because people always like to take pictures with their phones. If you need any help, you are not alone. Reach out to me in schedule or time. I can be emailed to, you can call me, my phone number and a way to schedule time with me will be in this announcement that this video came in. Don't be afraid to rehearse. Rehearse with me, rehearse with your friends. Just don't be afraid. Keep yourself COVID safe. Last year, out of our 10 speakers, we have 15 speakers this year, three of them got sick. I'll tell you this. If you're being paid to speak at a conference and the conference attendees are coming to see you, just take a little bit of effort. If you don't wear a mask, wear a mask for two weeks before the conference, just for those two weeks. Keep yourself well. First, it's the best thing for you and your family. We don't know how COVID is actually playing out for everyone. And the second thing is, you just wanna be healthy and excited, right? You don't wanna show up and be just getting over something or have to miss it.  Sorry, it's not much we can do. I suggest as often as possible, getting some much possible rest as you can. And like I said, wearing a mask. Finally, remember that your future collaborators, peers, friends, and people who want to believe in you and get to know you will be at this event. So whether you're at a career that you absolutely love right now or at a career that you think, I'm probably not gonna be here in six months, I can guarantee someone you will work with is at that event. I can think of two people. One was a speaker who actually have jobs right now from attendees who came to that event. Something to think about. If you need anything out, like I said, schedule time with me, call me, email me. Do not worry, you're not bothering me. My job is to make you look amazing for this event. That's it, that's my only job. I don't even have to worry about the audience. All I have to worry about is the speakers. With that, I hope this wasn't too long. If you made it this far watching the video, good on you. If you didn't make it this far, well, then you don't know that I'm even saying this. So yeah, okay, everyone. I will talk to you soon hopefully and take care of yourselves and each other.


Five, we saw money kicks Mr. V here. Welcome to another video guys. So into this video, I want to talk about some mining stocks that I'm going to be watching this week. Again, we've seen that Bitcoin and Ethereum or crypto actually pulled back massively and finally looks like they met support and set to reverse and curve back to the upside. So some stocks that want us to watch this week for potential swing trades or even day trades. That's what we're going to cover into this video. But before we get started guys, if you're new to the channel, we took about how to earn money, how to save money, how to invest and build wealth. So that's something that interests you. Go ahead and hit that subscribe button and the notification bell so you don't miss out on new content. Bitcoin and Ethereum are back on the rise. We've seen Bitcoin and Ethereum go down to the very lows and kind of find support. Bitcoin went to as low as under $30,000, which most analysts are predicting that it might go back to 20. And then Ethereum went down to under $2,000. And again, analysts are predicting that it might get back to $1,000.  So Bitcoin has gone as high now as $43,000. Ethereum has actually gone to $3,200. So again, if we look here on Coinbase, you can see Bitcoin up just 0.32% while Ethereum is down 0.24%. But again, Bitcoin is sending back those highs that we saw when it went to about I think $64,000. So hopefully this momentum continues to carry on back to those highs. And again, Ethereum went to a high of over $4,000 before that massive pullback. So again, we are talking about stocks here that when Bitcoin or when crypto moves to the upside, these stocks move to the upside. When crypto pulls back, these stocks do pull back massively. So they really mirror crypto in every chip of form. So the first one I want to cover here is Coinbase. Coinbase is one of the largest exchange for cryptocurrency and they started trading publicly just I think this year.  This thing opened pulled back, as you can see, to $220. And then it kind of like stopped moving back home. So this is just a month. So if it goes six months, you can see the high here all the way to $342. I think the actual high of Coinbase was over $400. I don't know why it doesn't show up on this chart, but it was over $400. So again, for me, Coinbase is in a very expensive one. So if you want to trade Coinbase based on the movement in Bitcoin and Ethereum or in crypto, if it's too expensive for you, you can trade it using options. So you can obviously buy calls. If you think that the price is going to go up or you buy put, if you think that the price is going to go down, but again, do some research before you do that. And if you're not used to options, then I'll say do some research there.  So do some research. Second one here, I want you to keep a closer eye on is Riot. Take a symbol R-I-O-T. This is one that we've covered here on the channel a lot. I've talked about Riot here, even when Riot was still under $2. I started talking about it here on the channel, and it's just continued to move up as Bitcoin has been showing tremendous strength. Riot has been going along for the right. So if we just go back here a month, you can see when Bitcoin pulls back or when cryptocurrency pulls back, Riot actually pulls back too. So you can see those bottoms there, and then as Bitcoin starts to occur back to the upside, Riot insert a call and start making their own move too. So again, I'm just using Bitcoin here because that is the biggest Bitcoin in Ethereum because those are the biggest cryptocurrencies that there is out there. But as a matter of fact, all the other currencies, all the coins that are out there, also just kind of these stocks do follow that same pattern. So the next one is Marathon, Digital Holding. So this one, take a symbol, M-A-R-A. Again, one that we've talked about here on the channel pretty much mimics Bitcoin's movement. Bitcoin goes up, it goes up, goes down, it goes down. If you look at Riot and Marathon, they are about the same. On this time, so you probably see some movement in Riot and a little bit slow movement in Mara. So again, you cannot either one of these Riot or Mara would still do the job for you if you pick one over the order. You're not going to be just completely left behind. You'll probably, maybe two or three percentage difference in terms of returns or losses, but it's going to be pretty much the same thing. Next one, and this one is a really interesting one because this one has just gone crazy just over the last month. So the next one here is BTBT. That's a ticket symbol. So we just go here one month. Look at BTBT guys. This is right here. This is July 23rd. Look at where BTBT was trading $4.23. Fast forward today. BTBT is sitting at $17. So that is insane. And again, this BTBT happened to just that movement when Bitcoin turned around. When Bitcoin went to the lows under 30 and turned around, BTBT followed suit and it's just on the rise and making a lot of people good money. So keep your eye on this. Again, this one is a little bit cheaper compared to these other two, Riot and Mara. So for people that have a smaller budget, you might want to consider buying ones that will give you a lot more shares and hopefully a ton of return. So then the next one here is FTBT. Be very, very cautious with this one because it's a Chinese-based company, but it's pretty much the same thing. They really trade with Bitcoin. The only question that I want to add again on top of the fact that these things are tied to Bitcoin is that with Chinese companies, you can see the Chinese government can just say something or get up and be mad at mining companies because they're using too much energy and guess what? The price is going to drop even if Bitcoin's price is going up. So that's why this particular one FTBT, you have to be very, very cautious. Same thing with SOS, another Chinese-based company. The same mentality here when you trade them, trade them with caution. And when I say trade with caution, guys, let me break this down. What I simply mean is when you go into these trades with these companies with FTBT and SOS, make sure that you have a stop loss. It's not one that you can just buy and turn around and walk away unless you have a fixed amount of money that you've decided that, oh, if I put $1,000 in SOS, if that $1,000 disappears, I'm fine. I'm comfortable. It doesn't bother me in a shape or form. But otherwise, when you put by these particular stocks, put in a stop loss so that you can limit your losses. And then you can give yourself another opportunity with another stock. Don't just go in and then watch it pull back because the Chinese government said something, and then you're not able to get out. So trade those precautions. And then I want to add two other ones that I actually been following, and I traded one of them in the past. The first one here is HUTMF. So this one is another one, same principle here, but these are over the counter. So these are OTC stocks. And so they are very risky compared to your regular stocks. Again, just do some research for this. You see they're still very cheap. And the thing here is, this is high risk, high reward. You can buy this and you think it just explode from $4.35 to $10 as well as it can pull back. So I traded this one. The next one I want to show here is HVBTF. So I traded this one in the past. I made some good money when they made a few runs. So they made some profit. So this is another one. Again, when you go into stuff like this over the counter, the only thing there is you have to be very careful because the volatility there is absolutely asinine. So I want you to be very, very careful. So there you go, guys. Those are some of the stocks. Again, I'm going to do a quick recap here of the stocks I've talked about. First one I want to cover here is Coinbase. The second one is Riot. The third one is Myra. Fourth is BTBT. Next is FTFT SOS and then two over the counter, HUTMF and HVBTF. So those are the ones that I will keep my eye on this week as we go into the trading week. As long as Bitcoin continues to keep this momentum and moving to the upside, and Ethereum is following that same direction, I think these stocks are forced to make a run. Even if it's just between 5% and 15%, that's a tremendous amount of gains that you can secure for your trading week. So definitely do some research on both of these. So there you go, guys. Those are my top five mining stocks for this week. And again, I'm basing these analyses on the fact that these particular stocks really closely matches what Bitcoin and Ethereum or cryptocurrency is doing. So when Bitcoin and Ethereum are going up, these stocks do move up. And I see Bitcoin and Ethereum to the upside. So that's why I'm keeping my eyes on these stocks for some potential gains for the week. So again, let me know in the comment section what other crypto or mining stocks are you following that I didn't mention in this video. I know there's a lot out there. Which ones do you have that I didn't mention in this video? Again, share those in the comment section if you're new to the channel. We talk about how to earn money, how to save money, how to invest and build wealth. So if that's something that interests you, go ahead and hit that subscribe button and the notification bell so you don't miss out on new content. Also, guys, if you are looking to get started with investing, Weibo has their promotion where if you sign up and deposit $5, you get free stocks and no cost to you. And now put the links in the description below. And as always, guys, do your due diligence.  Stay motivated.


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