cable modem -> wireless router -> desktop or laptop computer

While this article isn’t completely comprehensive and doesn’t go into the step-by-step details of solving every problem, this article will provide you with a wireless network troubleshooting outline to help diagnose your wireless internet problem.

First Identify the Parts
Before we troubleshoot any network connection (wired or wireless) we need to generally understand the components involved in the process. These parts are:

1. Cable Modem – this is the device that provides the connection. Usually there is a coaxial cable (the round thick one with the pin on the end) that goes from your wall to this box.  If you’ve ever setup cable TV then you’ve used one of the coaxial cabled.   The cable modem  usually will have many flashing lights (it will have more lights if you have cable and phone service coming from this same modem).  Note that the internet connection goes into the cable modem via the coaxial cable mentioned above, and leaves or comes out of the cable modem via an ethernet cable (the ethernet cable is the one that has what looks like a big phone connector on the end).

2. Wireless Router - This is the device that allows you to split your connection among multiple wired and wireless computers.   It receives a signal from the cable modem via the ethernet cable, and can connect to other devices via the wired connections (usually 4 of them in the back) or via the wireless connection (which of course, we cannot see).

3. Computer or laptop. Actually this can be any device that is cable of receiving a wireless signal (such as a laptop or desktop computer, an iPhone, and even my old iPAQ handheld which I do miss very much).

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What Can Go Wrong

When trying to figure out why your connection isn’t working, it’s important to understand the possible point of failures (POFs).  One of the most important questions I or any other technician will ask you is, “Did it ever work?”.   Suffice it to say that if a connection was once working and now all of a sudden isn’t working, is a much different story than if the connection never worked at all.  Let’s look at each device and see what can go wrong with each one:

1. Cable Modem:

POF: lost signal from the cable company. If this is the reason for failure, most likley the lights will no longer flash in the correct way or be totally off, and your phone service (if also supplied by the cable company) will probably not work, as well. Note that providing internet and phone requiers a much stronger signal than serving TV, so just because your  cable TV is working, doesn’t mean it’s still not a signal problem.  There are plenty of times that I’ve lost my internet connection and still had super high-quality HD on my TV.

SOLUTION: Check your wires and/or call cable. It’s rare that an individual wire will fail (E.g the coax or the ethernet cable) but it’s an option worth exploring.   But if all of a suddenly the lights stop flashing on the modem, it’s most likely a signal problem with your connection that is on cable’s end of things.  Try tightening the coaxial cable and unplugging and re-plugging-in  in the modem.   An intermittent problem is usually from a wire (e.g. it works and then fails every once and a while) or from the cable modem itself, but a total failure is likely to be from a loss of signal.

2. Wireless Router:

There are multiple POFs from a router so let’s take a look at each one:

POF: The router is broken (and yes, this HAS happened to me). In this case neither a wired or wireless connection will work. (Actually in my case the flash memory in the router died making it impossible to save any of my settings, so now this router serves as a switch on my network — but I digress).

SOLUTION : Look to see if the router is still flashing its usual lights.  If it isn’t, try unplugging the router and plugging it back in.  Some people (and Comcast tech support)  insist that in order to properly reset a lost connection (wired or wireless) that you must first shut down the cable modem, the router, and any machine that needs to get a signal (an IP address) from the router.  In doing this, once everything is off, count to 10 (yes, really) and then turn on the cable modem.  Once the proper lights are flashing (or are solid and on depending upon your company and model), turn on the router.  Once the router is up and running, then turn on the laptop or computer and see if it works.

POF:  There is a problem with the wireless connection only, but the wired connection works fine.  This situation is an easy one to test out.   Go ahead and test a wired computer and see if it works.  In my house I have multiple wired ethernet connections so if my wired connection is working but my wireless isn’t , then I know there’s something wrong with the wireless connection.  If you don’t have a wired connection from the router, you can plug in a ethernet cable to one of the ports on the router (usually numbered 1,2,3,4) and connect the other end of this cable to the ethernet port on the laptop (or whatever device you are troubleshooting).  If you can get on the internet on this wired machine, then you know that the cable modem and router are working and it’s likely a problem with the computer that’s trying to get the wireless signal.

POF: You can see the wireless router from the laptop or desktop but you cannot connect.
SOLUTION: Check to make sure that you are using the proper security settings.   If you can browse a list of available networks and you can see your wireless router (e.g. you can see the name [or SSID] or your router) but you still can’t connect, make sure that you have the correct password or other security settings.   You may want to disable all security on the router temporarily (you can read about how to secure your linksys wireless router in this article) so you can rule out security settings as the problem.

3. Computer/Laptop:

POF: The wireless radio (wireless network card) is not turned on or the connection is disabled.
SOLUTION: Windows uses the wireless radio to create a wireless network connection (in the same way it uses an ethernet card to create an ethernet connection).  Using Windows or software installed on the machine (e.g. Intel and HP sometimes have utilities to turn the wireless radio on and off), make sure the wireless radio is turned on.   Also make sure that the “Wireless Network Connection” is enabled.

POF: Your security software is blocking internet access.
SOLUTION: Check to make sure that your antivirus or security program is not blocking the internet.  I’ve had three situations where the security software had a “block all internet traffic” settting enabled, and that was causing the problem. Trend-Micro and ZoneAlarm (and other programs ) can do this.  An easy way to check is to find the security software icon in the bottom right of the screen (where the time and other icons are) and right-click on the icon.  Hopefully there will be an option that says “block all internet traffic” or something similar; make sure this option is disabled (or enabled depending upon what it says exactly) — use common sense.

POF: There is something wrong with the overall network settings on the laptop.
SOLUTION: Try to use a wired connection and see if the problem persists.  If you cannot get a connection even with a wired connection, it may be time to ask for help or call tech support for your laptop.  Sometimes it’s as simple as turning the machine on and off (or turning on and off the modem, router and computer as described above) — but after all of these steps if you cannot connect with a wired connection, there may be something corrupt in the network settings or possibly a virus.

If you’ve tried everything and still have no success, then it may be time to speak with technical support or ask for some assistance, and you can always post a comment here and I will try to help, as well.

Good luck!

1.  In the Tools menu select “Internet Options”.

2. In the window that appears, you will see your current home page listed.  In the example below it’s “www.cnn.com”.  To change the default home page, just type in the name of the new site you want to serve as the home page.  Make sure it’s in the format “http://www.somewebsite.com” (without the quotes).

Then hit “Apply” or “OK”.  You may need to restart Internet Explorer to see the change.

Remember — if your home page changed unexpectedly then this change may be the result of a virus, and simply changing the home page back will not solve the problem.  Be sure to do a thorough virus and malware evaluation of your computer  to get rid of any infections that may be present.

This type of filtering is an added level of security, as even if someone does have your network password, they still need to have a machine with a MAC address that’s “on the guest list”. Note that you can also restrict MAC Addresses as well, so if you know a MAC address that you don’t want on your network, you can specifically exclude it.

Before we can enable MAC Address Filtering, we have to know how to find a MAC address. This post goes over how to find your MAC address in Windows.

Now let’s head to the router to enable Mac Address Filtering.

1. Login to your router as usual.  If you forgot how, look at this post — it’s about how to change your SSID but it goes over how to login to your linksys router.

2.  Head to the Wireless settings and select “Wireless MAC Filter”

3.  In the menu that appears…

Click “Enable”.  And then select either the “Prevent” or the “Permit” option.   Personally I use the “Permit” option as that’s just like having a restricted guest list.

Then click on the “Edit MAC Filter List”. Go ahead and type the MAC address for each machine you want to allow on your network to the list. Press “Save Settings” at the bottom when you are done (I’ve blued out my MAC addresses in this image).

That’s it. Any questions?

1. Change the default router  password.  Here’s a post that explains how to change the default  router password.

2. Change the default  SSID.  The SSID is the router’s “name”, and for a linksys router is set as “linksys” as the default.  Change the SSID to something else — it doesn’t have to be complex but don’t leave it as linksys.   Here’s a post on how to change the SSID on a linksys router.

3. Once you’ve setup the other computers on the network, disable the SSID to hide your network.  Note that more modern machines can see networks with no SSID, but this step is an easy one to do and can still  help secure the network.

4. Setup WPA2 security (tutorial to come).

5. Enable MAC Address filtering MAC Address Filtering is a way to restrict access to your network by using a network card’s unique ID, or MAC Address.  The process is like having a restricted guest list for a party, and only people who are on the list can come in.

With these steps in place you can feel more comfortable about the security on your wireless network.

1. Open the  Command Prompt (shell).   Do this by going to START->RUN.  In the box type in “cmd” and hit enter.

2.  Then type “ipconfig /all” in the command prompt.

3.   You will then get a long list of entries and numbers.

Note that if you will have entries for your ethernet card and your wireless card.  In this case you want the physical address of the wirless card — since you are securing a wireless router.  Take a look a the two red arrows — you will see “Wireless LAN…” and “Ethernet adapter Local…”.

Look under the “Wireless LAN…” heading and find where it says “Physical Address”.  This is the MAC address of your card.  It should be in this format:

A1-4C-D3-01-42-5a

(I’ve greyed out my details here).

That’s how you find a the MAC address for your wireless adapter in windows. Any questions?

A:  You can easily limit a Google search to show only .PDF files (or any other file type for that matter) using the following syntax (let’s say your search term is:  ”microsoft word”):

microsoft word filetype:pdf

That’s all there is to it.

1) use the server’s ip address and the name of the account:

xxx.xxx.xxx.xxx/~userAccount

2) or use the main domain name of the account and the name of the account:

www.mainDomainName.com/~userAccount

This should tide you over until DNS resolution is completed.

Finding out all of this information (and more) is as simple as integrating your Google Adsense account with your Google Analytics account.   To integrate the accounts simply head to your AdSense account and login.  At the top of the page (under the header) you should see a link that suggests that you integrate AdSense and Analytics.  Click on the link and follow the directions.

It may take a few hours or a few days for everything to update (note that you won’t get historical data — which is really too bad) but once it is all connected you will find an AdSense menu choice in the Analytics “Content” area.  In this area you will now find a ton of useful AdSense data including total revenue, revenue/1000 visits, clicks per visit, CTR, and most importantly, a list of the AdSense pages that make you the most money. So what are you waiting for?  Go integrate your accounts and really make AdSense profitable!

Now on to the video…

Let’s use a simple example (see Figure 1. below to visualize the network layout). Say you have a server that is connected to 3 computers via a hub or a switch. When information (a data packet, or packet) is sent from the server to computer #1, via the hub, all three computers (1,2 and 3) will receive the information.

But if the server had sent the information over a switch, only the computer for which the data was intended (computer #1) will receive the packet.

So the switch, therefore, serves as a bit of a “traffic cop” in that a switch is able to “direct traffic” very efficiently from one computer to another, as opposed to the hub which in unable to do so.

The advantage of a switch is that in large networks, a switch allows data to flow more quickly because the computers (e.g. #1, #2, and #3) only get the traffic that is intended for them.