If I let my neighbor share my WiFi, can they see my network traffic?

Sharing your wireless internet access with a neighbor might seem like a friendly thing to do, but be aware that you are potentially putting your own computers at risk.

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I have a home network with three computers (two desktops connected with ethernet cables to a Linksys router; laptop is wireless). The wireless signal is encrypted and I gave my next-door neighbors my network key so they can wirelessly connect just to check email, do banking, etc. They are not on my home network, but can they still see where I am surfing (such as my bank site with passcodes, etc.)?

Let me, at least, make one important correction to what you’ve described:

If you give someone access to your wireless access point, you have given them access to your home network.

They’re on it.

Now, what they can see depends on a number of things but to be blunt…

I hope you trust them.

A Wireless Connection

It’s important to realize that a wireless connection – regardless of how your hardware is set up – is a connection to your network.

A very common scenario looks like this:

Simple Wireless Router setup

That’s a simple setup where multiple computers are connected to the internet via a single device: a wireless router. Some computers are wired, and some computers are connected via the wireless connection.

It’s important to realize that this is exactly equivalent to this:

Simple network setup using a wireless access point

A wireless router just puts the wireless access point in the same box as the router itself, but in either case it’s nothing more than a connection to your local network.

And of course machines on your local network should all be able to “see” each other.

About That Encryption

It’s good that your wireless access point is using encryption, but it’s important to realize what it does and does not do.

By giving your neighbor the password you’ve given them the encryption password. As a result, the encryption is not affecting your security with respect to them at all. It’s as if they were connected directly to your network - because they are. It’s almost the same thing as having given them a wired connection to your router.

The encryption prevent others – people to whom you have not given the password – from accessing your network.

But that’s all.

What’s the Risk?

There are three basic risks:1

  • If you have computers that share files or a printer among themselves, your neighbor may be able to access them.
  • There’s a tiny risk that depending on how your router routes traffic that your neighbor may be able to “see” that traffic. I call it tiny because routers typically do not route traffic to computers not involved in the conversation.
  • If your neighbor’s computer becomes infected with malware it may propagate to your machines.

To be honest, it’s the last one that scares me the most. The first two are all about your neighbor’s intention, which in most cases is probably honest and above board and is at least something you can attempt to judge. The later, however, involves your neighbor’s ability to keep their own system free of malicious software. That’s a risk I’d be reluctant to take even with the best of intentions.

To address your banking concern: as long as your bank is using https then I don’t see an issue. Https encrypts the connection between your computer and the bank, so even if your neighbor was able to see your network traffic they would not be able to decode your banking conversation.

Protecting Yourself

So, short of denying your neighbor access to your network, what can you do?

At a minimum turn on the Windows or other software firewall on every machine you have on your network.

A more secure approach is to use a second router:

Using two routers

The important characteristic here is that there is a router between your local network and the point at which your neighbor connects.

As I often say, a router acts as a firewall, and as such it has a “trusted” side – your local network – and an “untrusted” side – normally the internet - that it’s protecting you from. This setup draws that trusted/untrusted line between you and your neighbor.

Yet another approach is to get a wireless router specifically designed for this application. In recent years wireless routers have come to market that actually provide two separate wireless connections, one of which is isolated from your local network. While the intent is typically to provide access to the occasional guest in your home, the guest connection could also be the one you share with your neighbor.

One Possible Legality

Finally, there’s one more thing I want you to look into before you agree to share your internet connection with your neighbor.

I want you to check the terms of service with your ISP.

It’s very possible – perhaps even likely – that they explicitly prohibit this type of sharing (you’re taking away a potential customer after all).

While it’s unlikely that they would detect that the connection was being shared with a neighbor, if they did you could be penalized in some fashion.

This is an update to an article originally posted : July 26, 2005

Footnotes and references

1: Note that on a password-protected Wifi hotspot being able to access the hotspot does not imply that you can also sniff the traffic of other computers connected to the same hotspot. Even though the password to connect is shared among all users, in WPA and WPA2 the actual encryption key used for  each connection is different.

There are 69 comments:

  1. Jim Reply

    Actually, his router is most likely a routing switch, which would allow his neighbor to use ARP Poisoning to view traffic to and from other computers in his home network. You’re right, though, that traffic to and from his bank is probably encrypted (via https) so ARP poisoning still won’t enable his neighbor to actually read any of that particular data once it’s captured. Unencrypted traffic, however, would be vulnerable.

  2. Brian Reply

    That isn’t completely true. I agree that the obvious is the sharing of files and printers.

    But, depending on how techie the neighbor is, he could very likely see anything happening on the network. I manage our office network and have my computer set up to sniff all packets that carry thru to the internet. The neighbor could very well do that too.

    But then again, if he is able to do that then he is probably able to break a WEP anyway so you might as well befriend him and seek his loyalty.

  3. Andy Reply

    With regards to file sharing with all on the network, you should be able to specify which usernames/computers are able to view shared folders in Windows, right?

    If you share a folder containing files by right-clicking and selecting “Sharing and Security…”, then check “share this folder”, then click on “Permissions”, you should be able to add/remove individual user access. Default is everyone.

    Not sure if this only works with domain users, as a small home network usually uses a workgroup, unless you’re rich/clever/bored/mad and choose to use a Domain Controller for less than 10 PC’s.

    Also not sure if this is only available to XP Pro users.

  4. JoNNiE Reply

    Hey pholks

    i just got a bran new sony laptop it has a 802.11 b/n wirless card my brother lives 2 doors down and has his wireless network for open access so he lets me connect to it, But hes on holidays for 3 months and the signal strenth is low and i keep gettin disconected is there any type of a wireless attena i could get for it? at a decent price that would improve the singal strenth? thanks alot

    JoNNiE D

  5. lee Reply

    i dont have a wireless computer but a router and i have an anti-virus and a privacy guardian, is it possible for local people to see my web surfing?

  6. jeff Reply

    How do you secure it if i pc has xp home with no permissions feature and windows media center on other pc both of which have simple file sharing enabled how do i keep the neighbors from seeing shared folders.

  7. kracker Reply

    As a hacker I would like to tell you the dangers of wi-fi. Sure it’s great. No more running network cables through the walls. Wi-Fi is a goddie zone for hackers reguardless of encryption can be hacked. So no Wi-Fi is secured to really good hackers. They snoop through all your files on no matter what computer. And yes even if you had a hacker on your wi-fi he or she is too apart your network now. They can activate your web cam and watch and hear. It is a new scarry digital age. They can install pro rat which is a spyware program that can be changed by hackers to get pass your firewall or spyware scanner. Now they can monitor your computer from any network on the internet. Right now Im on a wi-fi and it is not my own. I dont have a wi-fi on my actual cable modem. I use a router and network cables because I dont take the risk of any other hacker piggybacking on my network. I suggest through the wi-fi networks out in the trash cause If I was on your network I could even look at pictures you have saved. I could even check you internet history even your cache for that matter. Nothing is safe with wi-fi. your just inviteing hackers to your network. They can be right outside your house launching virus or even sending death threats to the government and you get visited by the cops or fbi depending where your too.

  8. Leo A. Notenboom Reply

    —–BEGIN PGP SIGNED MESSAGE—–
    Hash: SHA1

    I’ll actually agree to a point. Unsecured WiFi, and WiFi using WEP encryption
    is, effectively, open to anyone.

    WPA encryption is much better, but it’s only as good as the password you
    choose. Choose a good – no, *great* – password, and WPA is safe.

    Leo
    —–BEGIN PGP SIGNATURE—–
    Version: GnuPG v1.4.6 (MingW32)

    iD8DBQFGYvhxCMEe9B/8oqERAuvGAJ9S4dA8zpp8JfRSsBj3CZCs7VvzHgCcCjfF
    SQbhDoRRRkPgbmJDlZYTs8A=
    =oLmN
    —–END PGP SIGNATURE—–

  9. Antonio Reply

    Well in response to the WPA is safe, I’d have to disagree on that. I’m pretty paranoid when it comes to securtiy especially on WI-FI reason being they arent secure at all being ur using WEP or WPA or WPA-PSK types of encryptions for the network, with the right tools they can be hacked, Someone using ARP poisoning places the hacker between you and the router making all the traffic pass thru his computer then to the router, this way makes his sniffing packets alot easier, even if your on a secured web page like ebay which the page uses https all the packets can be captured and decrypted with a program called (C&A) I’m using the begining of these letters to prevent others from using them but to the know hacker they know what C&A is. Well that is a method a hacker uses when already in a wifi network. But trying to hack a wifi network they first have to see what secured networks are in the area and they use a program called Networ Stumbler, that program detects all wifi signals in the area within range, this program can also detect wifi routers that have their SSID’s disabled from broadcast if im correct. Again i’m leaving some stuff out to prevent newbie hackers from getting ideas of hacking wifi,

    NetStumbler is commonly used for:

    Wardriving
    Verifying network configurations
    Finding locations with poor coverage in one

  10. Brenda Reply

    I have a business and I have WLAN connection. A lot of times I see my neighbor sitting near our building on the rock wall with his computer…. surfing. My guess is that he is using a wireless connection and fishing off my WLAN. I use a wireless and want to continue doing so but would like for him not to be able to connect and receive free internet from my business. What can I do to keep using my business base computer and also my wireless at the same time and not let the neighbor in? Thanks

    Enable WPA encryption on your wireless router/access point and stick a password on it.

    - Leo
    28-Oct-2008
  11. Pax Reply

    Worst Case: They enter your router through the network, jus typing http://192.168.x.x etc & they chance the router pwd!!! lo! and u r denied acces to your own router!!!
    wifi sucks, but then are there such hacker so easily avaiable??? guess not, a normal web encription, checked in 2-3 days, chance pwd as oftena as possible & its relatively safe…
    i mean relatively!!!
    NetStubler… well hats off… any wifi is crackable…
    tc.

  12. ramdon Reply

    you are all paranoid schizotypal disordered people!
    Most of what you say is true in theory but practically most people wont have to worry-because your average neighbor doesn’t have any idea how to hack into a network nor has the time. Its like saying not door lock is secure-with the right tools it can be picked-do you go to sleep everything night thinking about that?

  13. Jennifer Reply

    So as long as the neighbours are not using hacker tools, it sounds like the data going through that shared network may be safe from them. But what if they don’t have an anti-virus, or bother upkeeping it, and pick up viruses and trojans while surfing the net? Does having computers logging into your secured wifi but NOT your domain pose a security risk if they contain malware? THis may be an aspect that the person asking the initial question may not have considered; it’s also something I’m wondering about as I work for a school and we are currently letting students – with who-knows-what kind of security on their laptops – access our secured encrypted wifi. They cannot access our domain with their laptops as it requires an admin logon and is protected by various layers of policies. But can the wifi access alone be an open door to the system from an unprotected laptop?

    Any time you allow an untrusted computer to connect to your network – be it via Wifi, encrypted or not, or by a hardwired connection – you are putting every computer on your network at risk. Malware can indeed propagate to other machines on your network.

    Leo
    14-Mar-2010

  14. John Reply

    I agree with Leo. Any untrusted machines on your network can potentially spread viruses to computers on your domain even if they don’t specifically connect to the domain.
    I write software for detection of unknown computers on networks, and generally my customers are much more worried about viruses from home laptops then from someone cracking the WEP or WPA encryption and specically targeting their business.
    It’s just a much more likely scenario.

    I believe that many years ago this is exactly what brought a portion of Microsoft internally to it’s knees: a virus that someone had brought in from home on their personal or portable computer. Fortunately I was on sabbatical at the time.

    Leo
    31-Mar-2010

  15. Lauren Reply

    This answers part of the question; BUT, HOW to see what the neighbor has been accessing, at this point?

    In general, you cannot. You should assume that they can see anything without leaving traces.

    Leo
    15-Oct-2010

  16. Victoria Haynes Reply

    Thanks Leo, My questions have been answered. I’ve learned not to share my wifi. My neighbor came to me and ask if I could share the password to share the internet. They just moved into the neighborhood I do not know them.
    I google you and signed up for your newsletters. I feel better about saying “No”!!!
    Again Thanks.

  17. Rockr Reply

    Thank you for this information. I had a new neighbor asking for connectivity to my network over wifi. They just moved in and I was very unsure about it. This post helped take my decision in 5 minutes and do it so politely. Thank u!!

  18. Some User Reply

    Just tell neighbors you use hard-wired LAN and not WiFi. This way you won’t hurt their feelings.

  19. John Reply

    I have moved into a home and I have a Macbook and I watch porn. We share the same router. He is my landlord, can he track all the sites I use. They are adult sites and nothing illegal. I have removed the history and cookies, does this help

    Clearing history and cookies only helps if he has access to your computer. As the article you just commented on points out, he can see all your network traffic unless it’s encrypted.

    Leo
    20-Aug-2011
  20. Scott Reply

    In reference to the Wi-Fi ‘hackers’

    What about restricting access to only allow approved MAC addresses, hidden network ID, and having an encrypted password?

    I saw no one saying to hide the network ID, as well as the mac address.

    Here is another question that an answer may prove useful.

    Is there a way to allow a neighbor to use our internet, but actually on a separate “guest” network? Therefore, if his computer gets infected, mine can’t?

    Thanks!
    Scott

  21. sam Reply

    i watch porn on my ipod through wifi and i still live with my parents can they see my history on the pc even though i delete it on my ipod history every time after use???

    There are several approaches that your parents could use to notice that you’ve been visiting porn sites, even if you delete your iPod history.

    Leo
    06-Dec-2011
  22. Byron Reply

    I have a setting on my router to set the number of connections allowed at one time as well as a tracking log that emails me a log file of network traffic and sites that anyone using my network/internet visit. Highly recommend this for anyone with kids/teenagers. I can also set a time limit and the times that the connection can be used, password protected. The downside though is that if the modem/router is manually reset to factory settings, all settings are deleted along with the security passwords. So, protect access to your modem/router. I agree with Leo as to the legality of sharing the WIFI with a neighbor. That could be breaking your contract agreement with the ISP. As for the porn being streamed over the internet, the ISP should be policing that and limiting access. Those who want to access porn over the net should have to register with their ISP for a fee and permit like pay per view channels. As for kids, parents can set most modems/routers to block sites and activities. The modem firewall has many settings that can be password protected. Another caution on sharing your WIFI with anyone, they can upload/download anything using your ISP connection and it shows up on your record log of use and sites visited. You are held responsible for any/all activity on your ISP connection. Nothing is 100% secure on the net. Personal privacy doesn’t exist, your information can be accessed at any time without your knowledge of it being done until the authorities knock on your door. Last word; don’t share your WiFi with anyone outside of your household/family. If you set up a Guest Acct for a visitor, delete it when they are done with it. Any files/media/printers that are shared on your home network are accessible to anyone with access to that network.

  23. Byron Reply

    I live in a 20 unit apt building. There are at least three other wireless/WiFi modem/routers in the building or nearby. I have checked them out when they show up on the wireless connections. One out of three is an unsecured connection. Leaving it open for anyone to connect and access. At times when I have found an open unsecured connection and am able to, I send an alert to the site that their connection is not protected. Many ppl don’t know how to set up a secure WiFi connection. Especially when leaving their connection open for any Guest to connect via WiFi. If I don’t need my WiFi on or will not be using it for a while, I shut it off via the modem/router wireless settings. If you don’t use your WiFi often, shut it off. It only takes the click of a button to turn it off and on. And it keeps others from connecting without your knowledge.

  24. Thom Reply

    You might as well give your neighbor a key to your house to use while you’re on vacation. If you have bank account numbers, passwords, etc, sharing your network (wired or wireless) will give them, (and possibly their children’s friends who visit) access. Do you really want that? don’t be so naive, lock your system up as tight as you’d lock your doors in your house.

  25. Rick S Reply

    This is what happened to me a few years ago.

    I gave a friend my router password and told him not to tell anybody. Next thing you know his other friends are using my system too. I just don’t do that any more. Unless my guest is from out of town.

  26. Brad Gaston Reply

    Just a short story, if you allow neighbors to use your internet. I own a small IT business, and allowed a neighbor I have know for some time to use my internet. One day, three very big guys that didn’t smile showed up. To make a long story shorter, the neighbor had sent a threatening email to his ex-wife, they tracked it to my IP, and all my computers spent several weeks at the police station undergoing forensics. Luckily, I got them back with my data. Just a warning, if you loan out your intenet.

  27. actionjksn Reply

    If you’re going to do it and you trust your neighbor not to do anything illegal, then you should at least use two routers. When I travel and stay with people I bring my router with me along with an extra Ethernet cable. You simply plug your cable into the yellow port on your router and the other end into one of the ports on their router that are usually used to make a wired connection. This gives you your own network. If somebody wants to use your connection then they should have to pay for the extra router, they can be bought very cheap these days.

  28. Bill K Reply

    So I am confused. If I let my neighbor use my WI-FI, he can see my activities on the net. But did you say that I could NOT see his activities? Surely I misunderstood.

    No, I will not let my neighbor have that privilege, but nosy people want to know.

    I don’t think I said that. When you give your neighbor access to your WiFi in a sense you’re acting as his ISP, and can indeed see everything he does that isn’t encrypted.

    Leo
    06-Jul-2012
  29. actionjksn Reply

    One more thing you can do that will help with security. If you don’t need to share files between computers, when you first establish a connection to the network with Windows 7. It will ask what type of connection you are on, Home, business or public, Chose the one that says you’re on a public. It’s the one they recommend for coffee shops and other public connections. This way the network sharing doesn’t work. Just don’t select home even though you’re at home. Unless you need to share files between computers on your network which I don’t normally do.

  30. Peter Brooks Reply

    Two things occur to me. One is that if you specify a unique workgroup name for your machine(s) and make sure your neighbor/other user has a different workgroup name for their machine(s), you shouldn’t have problems with any party accidentally viewing each other’s traffic. If your neighbor suddenly renames their workgroup to be the same as yours, that’s a deal breaker.

    The second thing relates to locking down your network – which you should be doing anyway, whether you allow other users onto your system or not.

    Restrict the number of IP addresses that are allocated to no more than can be legitimately connected. Specify named systems that are allocated to specific IP addresses that you assign. Get the MAC addresses of every system that’s going to be using your router and restrict access to those only.

    Switch off broadcasting so that it’s harder (but not impossible) for war drivers to see your router. And create as long and unintelligible a password to your router as you possibly can (there are websites that will assess proposed passwords for you and tell you if they’re any good). This is one you CAN write down somewhere in case you forget it.

    Install a decent firewall. ZoneAlarm do a free version if cost is your main concern, and it checks incoming and outgoing traffic. True, it can be a pain sometimes but being stopped and asked if it’s OK for an application to access the Internet is far better than knowing nothing at all about what’s going on behind the scenes on your machine. Insist that your neighbor also installs similar protection.

    Hard core hackers would have no trouble getting past most if not all of these precautionary measures – but why would they want to? It’s like worrying that a drug cartel might “borrow” your bicycle to shift ten tons of marijuana. T’ain’t gonna happen.

  31. Gord Campbell Reply

    There are several more downsides to sharing your Internet. Just two: If your neighbour spams people, you may find that you send email, and it gets rejected as coming from a spam site. Or perhaps he sets up a kiddie porn server, and then you’re going to have a very large legal bill.

  32. Ben Reply

    A lot of new routers have the ability to setup ‘Guest’ access. Guest networks are separate from your own wifi network, with a different SSID and a different Password. Although your shares and machines will be protected from your guests, you will still be responsible for any misuse of your internet by your guests.

  33. Yorky Reply

    One thing that hits me that you seem to have overlooked. What if that neighbour uses it to do masses of download (like movies) and pushes u over your limit with the ISP and ends up costing you for the extra download (or at a minimum slowing your connection speed because ISP moves it to slower rate because you have exceeded the limit)

  34. Steven Reply

    You had also best hope your neighbor isn’t doing anything egregious/illegal or the men in blue will probably cuff first and ask later…

  35. DaGeek247 Reply

    It’s funny, but I don’t think Leo stressed the trust thing enough. I have actually been learning how to watch the traffic of others on a network, and even how to steal the passwords they put in. It’s so easy that there are tools that do it for you.

    That being said, if you trust your neighbors then it’s not an issue. Also putting yourself behind a second router will stop that from happening as well. I suggest you make absolutely sure that you trust them.

  36. Bob Stromberg Reply

    I would not give a neighbor my WiFi password under any circumstances.

    Further, I would further secure each computer by…

    – On Windows, make sure that the network you connect to is treated as “Public” unless it is a network that you trust completely and have taken pains to secure. That means that you trust every device that connects to that network. Then you can treat is as “Home or Office” and turn on settings like “network discovery.” Once you have chosen “Public” as the kind of network, open the “Advanced Sharing Settings” and ensure that the “Public” profile settings are tightened up. Turn off Network Discovery and review all the other security settings.

    – On Mac, look through the settings and review the “Sharing” settings. Don’t forget Network and Sharing settings, and the sharing settings in iTunes, iChat, and iPhoto.

    – On your WiFi router, check the “wireless isolation” (or “AP isolation”) setting. You might want to turn this on, at least for your guest networks. Don’t forget both the 5G and 2.4G networks. You might actually have 4 networks! (Why have more than two?)

  37. Charley Reply

    I think you just taught me something about my own router. I use a cheap Linksys E1200, and the Cisco connect lets me set up a 2nd access for guests. My guests are happy with it, but now I think it is the special 2nd connection you recommend. I just took that to be standard.

  38. cher staite Reply

    If you travel and use the wireless connection in a rented condo …. can the other guests and/or condo owners also see all your stuff?

    It depends on how it’s configured, but you should assume that the answer is “yes”.

    Leo
    02-Apr-2013
  39. Interociter Operator Reply

    My Belkin router has a setting for a DMZ where I can put a server to run games on with people on the internet. Could I put the neighbors machine into the DMZ port and be safe?

    I don’t believe so, no. Your machines won’t be protected from them. (And on top of that, THEY won’t be protected from the internet.)

    Leo
    03-Apr-2013
  40. Alex Dow Reply

    I suggest that in the third diagram-

    “Router 1″ should be labelled “Original Router”

    “Router 2″ should be labelled “Added Router”

    That then allows the owner to make the changes, without the neighbour being aware.

    Also potentially “Added Router” could have its own similarly-secured WiFi

  41. Rob Reply

    With my WiFi (Netgear 4300), I can set up a guest account. I assume that should be safe.

  42. steven Reply

    Guess who gets prosecuted if the neighbor views kiddie porn or does file sharing? He should stop sharing the connection with the neighbor, right away. A guest of the neighbor can do these crimes, too. The neighbor may be more than willing to share the key with others, it is not his connection, after all.

  43. Alan Jones Reply

    Letting someone share your wifi is a bit like lending a friend money, you may lose both.

  44. Peter Reply

    Ignoring what has already been said, and I concur with steven, what about password protecting the shares on the wired computers?

    While that may protect those shares, it does nothing to prevent other network traffic from being intercepted.

    Leo
    05-Apr-2013

  45. xrayangiodoc Reply

    You should really think about what could happen if your neighbor downloads child porn. The download would be traced to you! Police at your door at 4:00 AM, search warrant in hand, sifting through all your files looking for that child porn. Threats of long imprisonment! Best not to share that connection!

  46. Robert Reply

    A friend in another business in my building gave me a unique password for his wifi system, just so I can use it when I need to when I bring my laptop there. Is this as bad as the situation in your article?

  47. Mark Jacobs Reply

    @Robert
    It’s exactly the same situation but in reverse. So, as long as you behave, there shouldn’t be any trouble :-)

  48. john o'meara Reply

    I implemented the two router solution shown by Leo for a small non-profit school so that parents could surn while waiting for their children’s lessons. The parents like it.

    Implementation was an incredible hassle, basically trial and error to configure both routers. Can someone give a lucid explanation of the way and better the theory bheind putting two routers onto different “subnets” so they don’t interfere with each other? Changing the subnet masks was not the way to do it.

  49. Tony Reply

    Never give your password for router to a friend or anyone even if you trust them you have no idea what he or her dose on the internet. Like one comment said child porn how do you no he or her dont look at it. best to not do this i would re set it if i was you.

  50. Vito Reply

    John O’Meara:

    This is a little long-winded, but I have done this for both my home and my office to separate all wireless clients from my

    wired network.

    A router’s job is to separate networks, your private home network from the public internet. Let’s say for example you have a

    wired router for yourself, and a wireless router that you want to have available for guests. But you want the wireless

    network to be separate from your wired network.

    The simplest way to do this:
    First thing is to hard-wire your computer to the wireless router ONLY. You will be making changes to the wireless network

    setup and do not want to be disconnected midway through. Don’t worry about internet access as all you are doing is

    reconfiguring the wireless router for right now.

    What you are trying to accomplish is making the wireless router have a different LAN IP address & IP range than your wired

    router.

    Example: If the wired router’s local LAN IP is 192.168.1.1 (What you type in a browser to configure the router) you can

    change the wireless router’s local LAN IP to 192.168.2.1, (Or 10.0.0.1, whatever) and leave DHCP enabled on the wireless

    router so it can hand out IP addresses to wireless client’s.

    The wireless client’s IP addresses will be part of the 192.168.2.x network and not the 192.168.1.x network. You can leave the

    wireless router’s subnet mask as 255.255.255.0 or if the wireless router changes it, that is OK too.

    The only thing left is to set the wireless router’s WAN IP. It probably will get the IP from the wired router’s DHCP, but I

    like to statically assign it using a higher IP outside of the wired IP range (Ex 192.168.1.254). The WAN IP of the WIRELESS

    router has to match the LAN IP range of the WIRED router. This is where a lot of confusion occurs.

    When you plug the wired router’s LAN port into the wireless router’s WAN (internet) port you are separating the 2 networks.

    Nothing on the wireless side can see or connect to anything on the wired side & vise-versa.

    The only problem doing it this way, since they are TOTALLY separate, is administering the wireless router through your web

    browser. You can do it through a wireless client, but if you want to do it from your wired desktop you need to enable port

    forwarding on your wired router to the remote management port of the wireless router, typically 8080.

  51. Jack Luxon Reply

    I must confess that I have NOT read every reply as I feel my problem is slightly different. I lent my laptop to a neighbour, he used it Online using his router. Now I find that intermittently when I power up my connection defaults to HIS router rather than mine. I have no interest in his router traffic, or anything else on his computer. How do I stop my laptop ‘finding’ his router?

  52. DJ Reply

    After reading these posts I have decided NOT to ask my neighbor if if i can share their internet connection. I am looking for a new job and I cannot afford an additional $50/mth. added to my already obscene cable bill. I am positive my neighbors aren’t hackers or pedophiles. I guess it was a bad idea. Now I will worry about all wifi hotspots. Thanks alot.

  53. Julia Reply

    Hi i been reading alot of the comments but mine is a little different i have the xfinity router and my neighbor keeps trying to hack her way on the wifi for her computer without my permission i don’t want her on there have changed my name and password but she still tries to get on all day like a job sometimes she does sometimes she doesn’t. I use my laptop and Netflix and have to change all the passwords again Please help and tell me how to turn off my wifi until i need it for my iphone ..Thanks

    • Mark Jacobs Reply

      If you have a good strong password on your wireless router, it would be next to impossible for your neighbor to guess your password. You might find instructions on how to turn off the WiFi in the router manufacturer’s website (not Xfinity’s site). Or you might try phoning Xfinity’s support number.

  54. Terry Johnson Reply

    Hi, I have a wireless router that I have installed in my neighbors house wired to their wireless router. I have my set up as an access point. I know for a fact that the router that mine is connected to is one that has a snooper thing on it… Is my surfing visible to them?

    • Leo Reply

      A “snooper thing”? Short answer: if you’re using their internet then yes, they can see you surf.

  55. Neil McPherson Reply

    Perhaps you might find this to be of interest…

    A man received the following text from his neighbour:
    “I am so sorry Bob. I’ve been riddled with guilt and I have to confess. I
    have been getting onto your wife, day and night, when you’re not around. In
    fact, more than you. I’m not getting any at home, but that’s no excuse.

    I can no longer live with the guilt and I hope you will accept my sincerest
    apology with my promise that it won’t happen again”.

    Bob, anguished and betrayed, went into his bedroom, grabbed his gun, and
    without a word, shot his wife.

    A few moments later, a second text came in:

    Damn Autospelling…I meant “WiFi”, not “Wife”.

  56. Darlene Reply

    Hello, I have a wifi modem provided by telus. It’s an ZyXel brand. Someone was using my ipaddress so I strengthened my password on my wifi network. I saw a neighbour in the hall afterwards holding what looked like a wifi modem. I was too shy to ask what he was doing. But I suspect he might have been up to no good.
    Anyway, I connected my iMac to the wifi modem’s LAN with ethernet cable. I don’t know how to turn off the wifi on the modem or even if my computer is at risk if I’m using wired connection through a wifi modem?

    I’m concerned about identity theft mostly.

  57. Kenneth Reply

    It is a shame that the router model wasn’t described in the question. Most modern mid to high range routers can use guest networks today. These networks requires that the person deliberately hack into the rest of the network to see any activity at all.

    Personally I use an Asus-n66u. In my opinion the most effecient, handy router used in private networking. I need the speed it provides because I host net-parties where I have my ISP bump my net to 300/300mbps.

    The n66u can divide single ports from the rest and assign permissions from for each MAC address. It also has guest network as I mentioned earlier with a separate password.

  58. Sen p thomas Reply

    hai leo..how do u do..
    i want to acess to wifi network with my friend who is staying in third floor of my apartment and i am in 1 st floor..my friend is ready for sharing his wifi to me..but we both tried two three modems but i am not able get signal strength in my room..he is having an ADSL connection..can you please find a solution for us..the distance between the floor is not more than 15 mtrs..i am waiting for your reply..thank you

  59. Tom Reply

    I have weird porno sites on my memory that I did not go to. I always suspected my neighbor was stealing my wifi. Is it possible his activities show up on my computer?

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