Network Fundamentals Part 4

now security or we call a VPN a secure a private virtual private Network a virtual private network is creates a secure Channel between a server uh user and the server by connecting uh pipe okay what we call the VPN pipe to a VPN server now before VPN everything is in the clear okay and we are okay with it because there are little user uh on the network uh most of the user know each other and there are not a lot of criminals there not a lot of money flowing on the internet but as the number of user increases as the number of application increases as the number of uh the value of transaction increases okay uh more and more cyber criminals comes in and try to sneff data try to sneff things off the transaction right and users especially uh remote users they typically connect to the internet via what we call a unsecure untrusted Channel like for example you use a Wi-Fi on your in a hotel right or use a public Wi-Fi or you use your home network okay your company server cannot beess should not be accessed via such a casual method because you don't know who is providing the Wi-Fi and so on and therefore they will be able to e drop okay or to steal data off the network so what we want to do is to create a secure Channel okay secure Channel between the the remote user and the and your your remote uh server okay by creating a VPN Channel okay to the VPN server so you can see that there's VPN tunnel which is represented by this pink uh area okay and when this channel is uh been created all the data that is been transmitted over this pink area is encrypted okay and the the only the VPN server is able to decrypt it and then send it over in the clear to your remote server and when the remote server reply it goes back to the VPN server and encrypt it again and send back to your remote user right so VPN is uh very uh crucial in today's world okay by allowing you to create create a secure channel to conduct the network activities right it is increasingly used for remote workers and in uh public network right however there are also some uh security concern that you will need to uh be aware of for example some data leakages okay uh week encryption so you need to make sure that the uh VPN server that you use use strong encryption you also need to be using a trusted VPN provider okay because a VPN provider that is not trusted uh you are at their Mercy right because they actually hold the encryption key and therefore they can technically uh decrypt anything that goes onto the channel right it is also uh potential that you are uh uh to a man in the middle attack so the VPN setting is not safe the attacker can get the chance to intervene right so if your if if for example the uh remote uh some hacker has compromised your DNS server and it insert itself in the middle so basically they will create a VPN server between you and the VPN server and they can decrypt anything that you pass through right so that is uh we call it the man in the middle attack right again uh performance tradeoff okay because things are encrypted so it tend to be a bit slow but in today's uh Hardware uh this performance tradeoff is not a not too much of a concern unless you are running of a very very old uh machine right Network Tools there are some simple Network Tools that uh I'm going to just introduce for example um host name it's Command right that will shows you the network name for the host okay uh IP config or if config okay it is a program that let you view the status okay of a network okay so if config is used in uh Linux and ip config is used in Windows right the other command that is very useful as a tool is called the pink right uh Pink allows you to establish uh connection okay either from IP address or from a host name okay it tells you that uh the host is up although the host the connection to the host is up or not right this SS a what we call icmp Echo request right and the reply will actually be the echo reply another uh useful tool is called the trace route tool now trace route tool trace route is actually a uh Linux uh command Trace R uh in in windows we call it a tracer which is TR r a c e r t right Tracer okay so the spelling is a little bit different from uh Linux and also on Windows okay uh so Trace R is a tool to determine uh the route that has been taken so basically what you do is that you actually send pink uh to the individual route server acoss cross the rout right so if if for example over here you you will first ping the local machine the local Gateway and then you ping the next one you ping the next hop you ping the next hop until finally it ping the destination right and in fact you ping it three times ping it three times that's the default uh configuration for Trace Dr next stats is the command that will show a list of information about the current state of the whole uh networking subsystem so you will uh list out the rout table you will list out all the port that is open for listening meaning listening means that it is actually taking in connections so it's acting as a server okay so for example over here you know that it is uh uh this machine is a HTTP server it is is also a uh FTP server and so because it's listening to all the uh well-known ports right and is also have some uh established connections okay that mean meaning it is also connecting to other uh servers for example right so this is called the next St another command that is very use not very useful okay a command that is used for Network scanning okay is uh mmap okay it's a it's a powerful tool that is used to discover holes on the network automatically uh you can scan the network and you will discover uh all the ports that has been open on the servers and all this stuff now be very careful of about using mmap because it is uh it can be view as a threat because it you will if you put in the wrong parameter it can be very aggressive in scanning and you will it can be it can trigger uh alerts in your network monitoring tools and you so make sure that you know the command make sure that you tell the network administrator that I'm running mmap if you're running it against uh office uh environment for example of course if you you run it in a control environment in your own lab and you run it in your segment that you control then obviously is fine okay but if you are running it in your office environment you're running it in uh in a monitored environment make sure that you uh appropriate uh Authority there are other uh tools they can be used together for Network scanning uh tools like metal SP uh next scan uh IP scan and so on that can be used to uh do Network scanning as well uh Network sniffer Network sniffer uh uh uh tools that allows you to capture Network packet now of course we have learned about uh uh wire Shar or there are other there there are of course other network sniffing tools that you can use like TCP Dum and so on that that can be used to capture the uh Network packet for you to analyze okay now emerging technology okay I'm just going to go through some uh emerging technologies that uh you may may be interesting to you okay uh software Define network is a uh is a way to use software based controller or apis communicate the hardware so for example you can have all your switches and all your routers uh layout in the in in the hardware and you can actually use software to control the configuration and you can switch the configuration based on your uh needs in in terms of your company needs or your campus needs so you can deploy different configuration on the same piece of hardware and switch your network configuration right so this is what we call software defined networking right um so you you don't need okay not that you don't need you still use Hardware devices but you you actually control the hardware devices in the virtual Network okay and then you you can run your deployment your your um configuration uh from the from the software site right iot or Internet of Things networking okay this is uh when cars drones fridge winging scale power meters uh anything you can think of is also connected to the internet and therefore they need uh address so they have IPv6 address uh they also connected to the when okay either wirelessly or via Network so all this creates extra layers of privacies of security that you need to to hindle and um internet uh Internet of Things networking although it is not uh very um what we call uh usually they managed by the manufacturer they are managed by the uh uh isps uh if a company needs to let's say for example uh have a Smart Warehouse uh smart manufacturing where the the sensors and so on are actually iot devices and that's where you have to consider uh the different uh ways of interconnecting them and the security concern as well right now the next thing of course uh the 5G okay a lot of uh countries has already have 5gs implemented but probably in the partial manner or so on and of course we are looking at uh for uh 6GS expected in 2023 okay uh so 5G is 10 time faster than 4G and 6G is 100 times faster than 5G so 6G is actually 1,000 times faster than 4G uh and it and this four 5G and 6GS work hand in hand with iot devices uh iot devices while they can still work with 4G not so uh they're not so good uh when when the network is slower and the bandwidth doesn't catch up uh with them okay um because as if if if your if your drone needs to uh transmit a large uh photos a map or you need to upload and download a lot of images and so on between the Drone and the uh and the server while they are still flying means wirelessly then your network will need to have a very very high bandwidth okay something that 4G may not be able to uh provide they we need to have 5G and if not 6G okay so here we come to the end of the presentation uh on the igco network fundamental additional topic uh thank you for your attention