Free Software Foundation, Inc. v. Cisco Systems, Inc.

Transcription

Cisco Certified Network Associate Day One. Welcome back everybody. I am Imran Rafai, your trainer for this entire series. Today we would be starting with network fundamentals and when I say fundamentals we would deal with the very very basic of the networking industry. So this video is not only for the people who are going for the CCNA certification but anybody who's interested to, OR looking to start a career in networking feel free to watch this because you are going to learn as lot. But CCMA as a certification, is a very valuable certification and I urge everybody to go ahead and take that certification because it is gonna add a lot of value. Before I go any further I would ask everybody to concentrate on the first three days of our video because we will be covering the very basic concepts which, if I can dare, I would say is going to be the base of your entire networking career, maybe even twenty years from now. So please concentrate and be clear with every concept we cover here. And in case you still have doubts please feel free to email me at [email protected] [email protected] [email protected] [email protected] Alright, without further ado, let us get into the video. Let's start with the very basic question, "What is a network" well when I asked this question to my students more often than not I get answers like Facebook Twitter Picasa whatever whatever you see on the screen but well that is social network, that's not the network we are here to learn and that definitely is not the network I am going to talk about what I am intrested in is it this network the network between computers well this network is also the foundation or the base on which applications like Twitter Facebook picassa is built on. So we learn about this network and maybe if we have time over the course of this this series, we will talk a little bit about those applications here and there. While preparing for this video lecture I was preparing this a image that you see on the screen and I was thinking okay let me see how to explain this concept to students who are starting on at the networking industry so how do I explain this concept without actually using a lot of technical terms Or saying - 'okay this thing communicates with that thing over this thing' - I mean it was difficult and then I thought okay I need a better way to explain this and I i remember the story that a teacher of mine told me when she taught me networking. It is about the olden days of how Kings exchanged messages with the ally, they would pass the message to a messenger who used to ride on ha specs and this go through all these number the peep pot along the road and in the is to go through this did the city gate and then this go to other King and deliver the message so if you compare that to computer network the the messenger sending the message so the message is like the detail that you send in the data could be anything it could be a good doc file a Word document or it could be an excel file it could be any major could be you BDO it could be anything that detail and abroad on which the the messenger traveled that that basically is the network course computer network has much more interesting than just paving drawers up but if you if you see backed is the very pleasing my computer netbook is invented to communicate between computers if you see this image you would see let me just take a a highlighter you will see that we have the Windows PC we have Linux systems an iMac and we have laptop more bite for on palm top you have bebe so is maybe it's running on saint always him database server spite service but in spite of the all running on different operating systems they all can communicate absolutely perfectly with each other this is the magic of computer networks the computer network runs on ok a global standard called or same orders sand and and things like that which defines clearly what when any manufacture manufactures its a networking device what time how they should communicate with each other so the only language of networking and backed enables them to communicate with each other let's try to break this a little more further and see how internet works so if you look at the picture on your screens this is the very basic network to computers connected with the wire in this case we will use a catfight cable a cap to keep a look something like this: and this has becoming different colors you have blue-collar ones red color ones from and this is this obviously another color and this the out a Kabul is just a protective layer inside you have eight tiny keepers these keep it going to a connector called RG fortify keep it that looks something like this that you see on the screen and back of your computer and most the computer that you have today you have a port adj a port like this that is yard interferes your network interface card so your network interface card is ready RG fortify connects and using this you can communicate these two computers can communicate with each other this is the very basic form of networking and this is called as Ethernet ET hedge E arson net Ethernet let me just right down its E sorry book my handwriting and it's very difficult to right on screen especially with my mouse bat lemme chess eat net maybe for my next video out by ice time is so that I can just right tit more legible handwriting alright but for now up yes at this key believe connects between these two computers and you can have a very basic network but what happens if you have more than to computers so let you have fight computers me you obviously kit I mean there's one we obviously can't go on adding more meet network interface cards on your computer then you can have but a better bf connecting is by you making use of a networking device maybe a switch or hub of course which and how but two different devices they have totally different functions we will obviously learned about them in future we do. pursuits backed up for now you know we have a networking device in this case is a switch and these computers can communicate with each other so for instance this guy is caught over a document that he want to send across the network to this guy all he has to do is centered across to use IP address what is an IP address you would ask IP addresses how computers to recognize each other on the network the BB learn about IP addresses in the next I video series but for now just not be a identifiers for computers another critical reason why people use networking is because of devices like this in a maybe let's assume that this was a very expensive printer or scanner that the company invested in if networking was not available the wheat this device be connected is to this let me just check the college's sure that it is I okay lets you select to this is it would have had to be connected directly to the computer no let's assume that this user maybe print one beat Adi and maybe all the users in this computer in this company has similar requirement that they have to pre wanna poop eaters every day so the company will have been missed on more printer still have one more print area this guy will have one more printer so company will have unnecessarily invest on a lot of printers been the uses of damn in all the sprinters are gonna be very very minimal better before computer companies to invest money on IT infrastructures to how one compute one printer very expensive good quality printer light onto the network and everybody can print to it that's a lot of money saved and that's very efficient way of using it. budget so backed is the very basic requirement and the reason why we have computer network so a computer network in a local office you know maybe one home office and a rule mine are in a single company that's called as a lamb local area network and local signify that is very local to a geographer clearly a if this seem local lantz not desert Lance and you have not the land here and let's assume that your company has two offices one in New York and then you have another office in Boston wanna be you could communicate create a network between the the the two offices a few companies because we had to the kind of money that is required to cable from New York to Boston and of course if you can get the permissions you could run your own private cable from your Boston office to New York office no problem at all but not too many companies have that kind of money and not many companies would like to we aced that kind of money be a better way of doing it no you could connect your office to local ISP ISP is nothing but Internet Service Provider and the similar thing happens on the IBM Boston connects their office to an ISP Internet Service Provider and ISP's already have the backbone very massive a high bandwidth connections between the office she got beat da that you sent from here course through the network to the ISP from ISB to the ISBE in Boston and then through that to go back to the Boston office and a computer to this computer can commit come you keep with this computer absolutely fine using the ISP not this farms the wide ATM network bad lands are into connected with each other to form a very wide ATM network and wide here signifies a wide geographical Adia it could be across the country it could be in different cities and then the same country maybe a different countries basically it's a web so dot is how it works now how to how do you connect from highspeed to York ER a locally and that's what would you can replace p when non months situation what happens is you you get a a jack on the wall you might have a smaller jack on the wall and y'all your land can lawn you just connected to the jack so from your from the sewage from that out of your company you connected to the check back and design a speedy would the leaked cable maybe they would kill aid under under the ground bill a cable to the office and from the office they go here from Denmark of it again maybe underground daily a cable Judah Boston office again there will be a wall socket that is provided and you just blow to keep from the wall to you your rotor and that's how you are when link works when this is also intended to be using the ISP intimate is nothing but a better team massive when which covers the entire world where you have a lot of public resources so if you google this is the definition of what an internet is a global computer network providing about it. of information and communication facilities consisting of interconnected networks using standardized communication protocols well that is pig definition I well that's exactly what it is you know internet is nothing but you have a lot of and do you have a man here you have a band here you have a plan here you have a ban het and then just brands are connected with each other so you have another ran here and you have another man here another one here another one here maybe fuel more here I know in India that up Whitelock you have all these things and get connected let's when singer connector from here connected here from here connected here at these disconnected this is connected this is going to this is connected this is connected so this is nothing but how an internetwork so for instance if from India somebody has to communicate to New York this is a hold the data transfer there in court if this thing disconnects you have somebody the data going through along a pop so this is what network internet is it is just nothing but interconnections of a lot of events let's find out more about applications were talking about earlier don't don't lot of use it off Internet are networking as a whole we have YouTube CNN EB Skype is just very ferried very very few examples that a use the Internet but they're Lord of sites and applications which use the internet as you already know know how it works is YouTube for instance is owned by Google to Google has put a public so a summit on the Internet that is accessible to anybody on internet so if I want to watch a video on youtube ice I go to my web browser and type www youtube dot com at the process that takes plays in the background is much more complicated I'm simplifying this would process we will look into exactly how it works in for this video series but for now when sometimes YouTube docked calm and hit enter my computer sends a HTTP request to YouTube's public sewer when summer gets that information it is %uh find that some HTTP request so I send damaged him if I backs it creates an html5 back and it sends an estimate fight back to me might that does it take seventies %uh that's an HTML file and I know how to process it so it processes that and your YouTube website come to life and you see them it shows a lot of videos and you click on one of those videos this process repeats they send you back to beat your and and that's how that works to similarly it happens to eBay you know you go to CNN Skype that's how it works so this is how internet works basically they have a public servant they put all the files there your computer request that this in the fight back to you and this is how a internet helps you run that this global global ice storm worked when we talk about instant very critically we need to talk about to speed up internet before we get to the speed up internet lets get to what is the difference between bit and bite bit is the smallest information computer can understand it's either 0 or 1 but as byte is nothing but for me it spawned by 8 bits so a bits together form one but it could be some like 1101 one 101 whatever something to that some bite so eight bits from one but now a lot of people get confused detail is always denoted by bites so when I say I have 1gb of RAM it is one key got bite RAM but when I tell I have a 10 Mbps connection it is 10 am BBS connection bits per second make up bits per second connection if you confuse these two it's going to be very very difficult at one Mbps bite per second connection is 8 Mbps connection eight games the speed of what it is supposed to be so speed is always denoted by the small be data size is always imus big be n in computer while kilo is always 1024 so one kilo bit is 1024 bit similarly one kilobyte is 1024 bite right so for instance let me see I have 1 Mbps connection and I have a fight of 128 KB bites so letter for instance you have booked an inward you type at the alphabet eighty now with one 252 to do that one alphabet thats takes about one bite capital be of myspace so one bite is how much it need to store this at for but 8 its one bite is about it is 8 beats right according the convertion so too baby it takes eight bits on one by to beat up alright having known that let's look at this example to you have 128 keep be that is bite file if I love 120 128 KB now it meets to go across Asus netbook puts be 21 Mbps one makeup bits per second how much time will it take to a simple question let's try to convert 128 kilobyte if he could what to do bits it is 128 into eat dip this conversion if you're not bit bite it's more eight right so one bite 128 byte isn't too if you convert it into bits it is 1024 kilobits of data right so one 24 kilobits where is that its 124 kilobits is nothing went 1 make a bit right on makeup it but the speed it is 1 megabit per second is the speed of our connection so on a connection to 1mbps 8 1mb fighting which take exactly one second so that's what speed is so I'm stumped this the difference between speed and data the difference but in bed and bite so if you can understand different but a bit and bite the whole process of understanding for the videos can be very very easy when we talk about speed we need to want to talk about three other critical factors that speed deleon available at three of them all these go hand in hand like for instance now when you can to keep you from your router to York PC it is you that is connected at 100 Mbps that's because today on land con a the maximum they can do is a 100 Mbps but they don't forget that speed that they're telling is the speed between your computer and the hotel your internet connection maybe you wanna bps connection so if you send 100 bps data 100 MB per second data it will not go to use internet because your intent can only do one Mbps similarly you go that fled to france does your banker office to New York office be sending a fight so from bangor office it goes through a gate be from get where we have a wanna be a slow connection it comes to our bangor ice-t_ bangor ISP to Mumbai is they have a 100 Mbps lay very fast and then huh from Mumbai to Dubai they have but any BP is limitless little slow connection from Dubai again to cairo they have 100 bps line and then add credit to Madrid Letty you have a 100 bps line to similarly they have a smaller hi addition different speeds around the world to basically when I send it to Internet this what happens intimate if you if you pull off the cloud it is nothing but a lot of rope is jumping could be here and that now if I even if I have a very high speed connection you're beat-up throughput between your bangor and New York office we depend on slow connections in between so even if I had up very high speed connection to 100 Mbps line Bangla right eat ken only travel at the slowest link in between so our stores link is the 10 Mbps land that we have here so from New York office band office it will August the magnet can do is the two the one MPs line that we have in now New York so this is how it works so I mean this is not the exact data flow from one bank go to New York I've just just giving an example it need not of his quiet by in credo the beat goes for some other other location but basically it actually that did the packet data packet flows through one location to another location to another location was so like I said the speed always depends on different factors of the link speed that you have one in between again there's a critical factor factor is of dealey no been a send the data from New York to Banglore it has two like him already discussed has to pass through a lot of Nord in between but let's assume that we have a lot of is in Boston I love Boston don't ahead so let's say we have Boston office an we senator from New York to Boston it has to pass through less number of nodes and Hans it would reach much more quick up so that's another factor if the distance between the two devices is long you will have delay in communication and that's what to do if you see if you go to Google I mean even Google Doc conferences are you go to %uh YouTube dot com det redirect you to a content delivery network closer to your place so PI in Singapore and you say Google dot com are you HOT you go to YouTube dot com YouTube would not connect you to the group with several YouTube server in United States e2 will connect your to up content delivery network close to Singapore may be in thinkable so that diz does not much a delay on days in significant delay in the communication and the the whole process is much much more first so that's that's the delay but if it and Republic again for instance the the link between Cairo and the by is down communication between New York and Banglore food not happen or it would happen but then it has to take maybe along about the might have another pot which cause why russia and then it comes why are and I know it goes why China and comes to India and annotate that's a long long long process sought thats another thing about available at every ability is is if all the links in between are up and running another thing we need to discuss in today s plea deal is network topology the network topology death three parliamentary network topology stock topology the ring topology and the bus topology the very very wooden ease of how computers work connected but even today's world they are in use I'm sure how know when to stop how to start work start is wet all the computers or devices are connected to a central switch are a connecting device know if this line goes down it doesn't affect everybody else only this guy cause of the network so in Greenpoint since every computers connected to each other so if this guy goes down the communication to in peace to devices can still happen through this way right so that's how this works none in bus topology let's say for instance this is a game like that you have a different device you're disconnected this devise you're not the device here that's gone back to every computer is connected to be a on little device right now if d-link goes down here this part of the network can communicate the each other but not with another device from the other segment of the net for that's how a bus networks let's see how it is implemented in today's but because back to our ordered example that we saw earlier in in this video and if you see this which and these data systems are the species are connected in a star formation everybody's connected to this entry switch here to serve all too similar thing happened in everybody's connected to the switch these devices are connected to the access point in stop on a mission are I and but also to see and if you look at the switch the switch is connected in a bus formation 0 if Dept link goes down here despite the network can communicate with each other but it cannot communicate with anybody is from this part of the network %uh sometimes you might even have networks where this is connected like this and this is coming to like this so even if this goes down this which can still access this network at around despite and they can you know get access to these these windows the mean these systems here so in good into real-world the network topology that we use is called hybrid which the makes use of the start and ring maybe I even but the bus so it's a combination of all the key art either of them and that's how it is so it is a hybrid that what the fuse in today's world I think that is about all the information that I wanted to speak about in this first video we will for the get into a lot of other topics in a second video this is the review of what we did today I go to all the I'll topics that have mentioned herein see if you understood any if you think you can always call back and tried Dunleavy added more a even of that if you have conclusion if you want more clarity on any topic these feed feed to right into in Ron doctor by at end up puking daughter large E and I've look into it and I believe and you we and of course subscribe to our YouTube channel and you Kim getting all our viewers live on you thank you for watching and his visit our website by