How Do Wi-Fi Range Extenders Really Work?

hello my name's gary sims and this is gary explains today i want to look at wi-fi extenders you may know them as wi-fi boosters or wi-fi repeaters wi-fi range extenders is probably the official name i want to bust some of the myths some of the misunderstandings about how they work and actually look at the details of what they achieve and how they achieve it so if you want to find out more please let me explain [Music] okay to do this we're going to need to look at several things first of all we're going to need to look at why you need a wi-fi range extender second we need to know about how an actual wi-fi network identifies itself and that's important and we'll see why in a minute and then we're going to need to look at how a wi-fi extender actually works and then because of that where's the best place to put it in your house to get the best results now wi-fi of course is based on radio waves and like all radio waves they have a strength now the average wi-fi access point your wi-fi router works about 100 milliwatts which is not a lot of power so of course as you get further away from the source the distance increases the signal strength drops off and you'll get to a point where you can no longer pick up that signal and there are other things that can cause the wi-fi signal to lose its strength and that's basically obstacles doors windows even big bits of furniture now when the radio wave comes up to an obstacle a couple of different things can happen it can pass through it and if it passes through it will have lost some of its power it could get reflected in a different direction go away get scattered even and of course it can just disperse in the material itself and just not penetrate it at all now as i discussed in my previous video the jargon busting video you can get wi-fi on 2.4 gigahertz on 5 gigahertz and on 6 gigahertz with wi-fi 6e now a 2.4 gigahertz signal can go a longer distance because it's better at passing through solid objects a five gigahertz signal gets stopped easier by walls and doors and even big bits of furniture however a five gigahertz signal can actually give you higher data rates higher bandwidth whereas a 2.4 gigahertz signal gives you less but it goes further so you have a choice between range and speed and it's often a balancing act and the reason you might need a wi-fi extender is where you want to pick up wi-fi and you're too far away or there are too many walls between where you are and where the access point is and so that depends on the size of your house if you're in a very small apartment that probably isn't really an issue if you're in a house if you're in a bigger building then you're going to have issues getting the wi-fi signal further and further away here in my house we can basically get it all over the place but as soon as you step outside for example if you wanted to use the wi-fi out on a balcony or out on a terrace out in the garden then the wi-fi signal disappears so a place for a wi-fi extender is to extend that range of the wi-fi so you can get it in other places in the house in my case out on a balcony or out on a terrace now when you start up your phone and you search for a wi-fi network you will see a list of wi-fi networks identified by some text and that's called the ssid the service set identifier and that text is what you set you may have left at the default that your access point provider your telecommunications provider has set it to but you can change it you can change it to whatever you want gary's wi-fi or whatever you want like that there are some limitations about size and so on but basically it's a string that you set yourself now because it's something you can set yourself there's nothing stopping you from setting all the wi-fi's in your house to having the same ss id because if you think about it that was the only way the network was identified it would be really confusing because when your smartphone or your laptop is trying to talk to the wi-fi and it's just using that ssid it doesn't know who it's talking to is it talking to this wi-fi router to that wi-fi router you know there will be lots of confusion so there is a second piece of identification which is what the machines use to identify not us as people and you generally don't see this in the wi-fi listing there are some tools you can get for android and so on that will show it to you but it's called the bssid the basic service set identifier and it's basically the mac address now the mac address is a unique address assigned by the manufacturer that each wi-fi access point each smartphone each laptop has and that uniquely identifies it so when the packets are flying around in the air they have an address on them where they're going to and where they came from and that's not based on the ssid that's actually based on the bssid so the actual smartphone can talk to the access point and the access point can reply with a unique address and all the other packets that are flying around get ignored because they're not for that particular device now if you do want a video on mac addresses do let me know in the comments below because they're quite interesting 48 bits they're how they're assigned and so on could be interesting let me know and i'll think about making a video now when you use a network extender the idea is this you set it up and when you set it up you tell it which network you want to extend which means it has to be able to authenticate with that network and then you move it to another room so that you can get further wi-fi access now the idea is that when you move from room to room with your smartphone it picks the strongest wi-fi signal now if it sees two uh wi-fi networks will have the same ssid or similar ssids at some point it will say this one's better and it will connect to the stronger one which is meant to be the wi-fi extender and then you'll get better connection between your device and the wi-fi extender then of course the wi-fi extender still has to talk back to the original uh to the original access point and then as you move around the house as you come back close to the original access point then the phone will swap again networks and that's how it's meant to work now some phones are good at doing that some phones are a bit worse at doing that they hang on to weaker signals because they say well at least i'm on this network i might as well stay connected to it they hang on a bit longer maybe and in fact during my testing i had to really be sure that the my test devices the laptops and the smartphones i'll be using did actually change to the extender rather than lingeringly connecting to the original access point now the key point to understanding network extenders network range extenders network repeaters whatever you want to call them is they create their own wi-fi network they're not actually extending the original network or boosting it in any way whatsoever they create their own wi-fi network now the ssid may be the same or even similar with maybe you know underbar extension on the end of it but actually it's its own wi-fi network and the bssid is unique and it's for that wi-fi range extender and so when your device connects to the range extender it's getting into a new wi-fi network now what the radio center does is that when it knows its job is just to receive that stuff on its own wi-fi network re-packing it up change the addresses so it's now going back to the original access point so it then re-transmits so its job is to receive rewrite the packet and then re-transmit them and then when the reply comes back it receives that rewrites the packets and then re-transmits them so it gets out to your smartphone or to your laptop now because of that the wi-fi extender is actually doing twice the amount of sending and receiving that your phone is doing or that the original access point would be doing because it has to receive the information and then send it on again receive it and send it on again and because it's using one radio and we'll talk more about multiple radios in a minute but generally it's using one radio so that radio is actually being split into doing its own wi-fi stuff and into sending the data onto the original access point that's why the extender will actually be on the same channel and using the same frequency as the original network because it hasn't got time to switch the radio to different frequencies you know when you're talking about you know mega bits of data going back and forth hasn't got time to retune that radio so in general as a rule of thumb a network extender is going to have half the bandwidth because it has to do twice the work now of course we do have uh wi-fi extenders with multiple radios inside them i cover this in my previous video so you basically got this memo mimo setup where you are able to use two or more radios two or more antennas that's the kind of the crude way of looking at it to send and receive information so in that case the actual the wi-fi extended can receive on one radio and transmit on the other and that does improve the bandwidth in fact i have an honor router 3 which i'm planning on doing a full review for and that is able to act as a repeater as both a 5 gigahertz and 2.4 gigahertz so in fact on that one you can connect to it on the 5 gigahertz and it re-transmits back to original access point over 2.4 gigahertz using two different radios so you do get improved bandwidth and this will also come important when we look at mesh networking which is one of the future videos i'm planning on doing so what we do now is look at some testing that i've done which actually demonstrates in a very practical way the problems and the benefits of using a network extender so here we see a kind of a pseudo map of my house it's not actually the map of my house but it's a pseudo map of my house now as you can see in the bottom left hand corner we have my office which has got a wi-fi network in it now if i connect to that best case scenario i did these tests many many times to get the best results let's say that the baseline number is 100 i get 100 bandwidth using a smartphone connecting to that router it doesn't matter what the actual number is because what we're talking about is the difference the variance of that as we move around the house now if i have a network extender properly configured to boost that work to repeat that never to extend that network and i have it in the same room then if i run my performance test on that i'm actually at 58 so you might find that a bit shocking so here i'm in the same room not very far away there's no real problems with going through walls or obstacles we're all here in the same room and actually just by using the extender my bandwidth has gone down to 58 now why is that in this particular case it's because i've created lots of interference now remember both of these wi-fi points are all using the same frequency because the wi-fi extender doesn't have time to switch frequencies so it's on exactly the same channel as my original access point and as i use it the room is being flooded with 2.4 gigahertz channel 6 whatever radio waves and they're all interfering with each other and so the bandwidth just goes down to 58 in fact you'll notice now in the next when we move to another room it actually goes up because we're reducing that interference and now we're introducing a second problem which is the distance away from the original wi-fi access point so if we move across the hallway into what here on this diagram is the bedroom now here's the interesting point if i connect to the original access point i get 73 percent that's just showing you the drop-off of going through two walls going a few meters away from the original access point i'm now at 73 percent now if i plug in the air network extender into that room and then connected the network extender the bandwidth is now down to 70 percent this is really interesting thing to note first of all the wi-fi extender has to itself connect to the original access point so if my smartphone could only get there at 73 that's kind of the number that it's going to get bandwidth-wise when it connects back to the wi-fi uh original wi-fi network and of course it's got antennas maybe it's able to have better reception because of that but overall it's not going to get any better than what you have using another piece of wi-fi equipment because they're both talking the same method wi-fi back to the original access point and then on top of that any gain that it has because it's got big antennas on it is lost because it's doing double that work as i explained it's trying to receive and then send and then receive back the reply and then send that again so you notice that actually using my smartphone i could actually get 73 but using the wifix and i get 70 so again in this situation the wi-fi extender is not helped in any way whatsoever if we now move down to the far end of the house and i tried to connect using my smartphone back to the original wi-fi i'm at 31 so again the distance and the walls has reduced that signal until i only get 31 percent of the original bandwidth but again we see the same situation if i connect in the wi-fi extender then when i try to do a test through that i'm at 26 so the bottom line is this if you can connect to the network using your original device you're not going to get any better performance by using a network extender because it's also connecting to your wi-fi using exactly the same methodology it's using wi-fi and it's trying to talk to your access point so again you have to be very careful about where you place these things however all is not lost it does have a purpose a wi-fi extender and that's what i'll show you now so if i go outside now leaving the wi-fi extender in that end room where we were getting 26 percent now outside my smartphone has no connectivity to the original uh access points too far away up the other end of the house too many walls can't get there but my smartphone can connect to the wi-fi extender and it can get several bars it can get good connectivity but the overall bandwidth is now down to 16 percent and so of course that makes sense if the wi-fi extender can only get 26 where it's situated then anything that i then go further away from it is going to make that signal drop down my connection to the wi-fi extender so it's always going to be a fraction of 26. the best i could get would be 26 if there was 100 availability between my device and the network extent i went outside there was a wall to pass through so now my device my smartphone is talking to the extender and the extender then talks to my original access point and i'm getting 16 of the original bandwidth however i'm getting wi-fi connection it might be quite low but i am getting wi-fi connection if i just use my smartphone i couldn't connect to that original access point so as you can see picking where you put in your wi-fi extender is important because on the one part it has to be able to connect a good connection to the original access point if it's too far away if it's too weak then that's going to your bandwidth they're not going to get any more bandwidth because it can't physically talk to it over the wi-fi and then of course secondly you talking to the wi-fi extender if again it's got the same wi-fi problems you go through walls we go outside if you've got you know big furniture in the way then it's going to interrupt that signal so you're always going to get a fraction of whatever the wi-fi extender can achieve at that point now of course there are other ways of solving this problem mesh networking is one of them i've got these really nice audience mesh network units i'm going to do a full review of those and they are tri-bands so there's three different radios in there and that solves some of the problems we've been talking about and of course you could use a wired ethernet between the access point and the uh the extending access point or a second access point and we can look at that if you think that's interesting do let me know and maybe i'll think about doing a video about that one person said in the comments about powerline adapters again that's a good way of solving that problem maybe i'll also do a video about that okay so what have we learned we've learned that wi-fi signals are transmitted 100 milliwatts and therefore their signal strength goes down the further away you get and if you go through more obstacles you can have dead patches because of that around your house around your apartment you can use a network extender but the key is that a network extender creates its own new wi-fi network it's not extending the existing network it's its own new wi-fi network and then it acts as a kind of a kind of a junction it receives in one things and then sends it back to the original point which means it's communicating with the original access point also over wi-fi and so if the wi-fi signal is bad at that point then the extender has bad wi-fi at that point and it can't connect to the access point okay that's it my name is gary sims this is gary explains i really hope you enjoyed this video if you did please do give it a thumbs up and it's best not to rely on the recommendation algorithm better to subscribe to the channel and even hit that bell notification icon okay that's it i'll see in the next one [Music] you

Channel: Gary Explains

Views: 201,670

Keywords: Gary Explains, Tech, Explanation, Tutorial, Wi-Fi Extender, Wi-Fi, Wi-Fi 4, Wi-Fi 5, Wi-Fi 6, Wi-Fi 802.11ac, Wi-Fi 802.11ax, Wi-Fi Range Extender, Wi-Fi Booster, Wi-Fi Repeater, 2.4GHz, 5GHz, Wi-Fi 802.11n, WiFi, WiFi Booster

Id: 0Z-C3P6F-KY

Length: 16min 36sec (996 seconds)

Published: Thu Apr 08 2021