How Do Those Ads Know Where I Live?

I live in Baltimore. When I go to a website,  the content will often say things like, “Find sexy singles in Baltimore,” and stuff like that. I use spyware software religiously. So, how do they know where I live? And how do I get rid of it? These aren’t local websites that I’m visiting by the way.

Spooky, isn’t it? I see the same thing when I visit certain websites. It’s not always about “sexy singles,” but they frequently nail me down to the Seattle area.

There are a couple of ways this can happen.

Read moreHow Do Those Ads Know Where I Live?

Does Opening Multiple Tabs Affect My Network Speed?

I’m an IT web manager where I work. We now have a new guy that opens 50 plus tabs in Google Chrome. Since he’s shown up, things on our network have slowed down considerably. Logic would dictate cause and effect.

Now, I know from seeing other posts on your site about people asking about having lots of tabs open and it doesn’t affect the network as much as the individual computer. But when somebody has 50 tabs open, say half of them are running JavaScript, different codecs, codes, heck some flash, some JAVA,  that’s all gotta slow things down, right? I’m not talking 20, I’m talking 50 open all the time. Now I know you can disable updating if you know how in Chrome; I’m a Firefox guy, myself. Less data mining the better. What do you think? I’d love your input.

The best answer that I can offer is… maybe.

I’ve talked about having lots of tabs open in the past. Without a doubt, it can definitely impact the speed of your PC. The network, on the other hand, is possible, but a little less clear.

Read moreDoes Opening Multiple Tabs Affect My Network Speed?

Does a wireless range extender compromise my security?

I have a home network: two PCs hard-wired to a Belkin router and a laptop Wi-Fi connected most of the time to the same router. The Wi-Fi connection is secured according to your recommendations with WPA2 and so forth, as confirmed by the small window currently connected. For outdoor use of the laptop, I use a Linksys RE1000 range extender. When I connect, the same windows show security type “unsecured.”

I tried to configure the extender as specified in the supplied CD (i.e. by wireless), but there’s no provision for security. Hardwiring the device gives access to the configuration panel, but there’s no provision to secure either.

My questions: Is the lack of a security setting typical of extenders in general or is it my model only? Is the situation insecure? I guess I’m okay on the internet side because the link to the internet is the Belkin which is secure, but what happens if someone picks up my extended signal? Could that someone interfere with my laptop? Thanks in advance.

It’s interesting. There shouldn’t be an issue here, but what you’ve described definitely makes me nervous.

Read moreDoes a wireless range extender compromise my security?

How do I slow down my router at night?

My wireless internet works very well. At night, my son will not get off the net. I want to slow down the internet to a crawl by changing a setting in the router so that my son will go to sleep. Can you tell me what setting I can change in the router that slows the speed down by say, 75%?

Controlling children’s internet activity is nothing new. Parents have been dealing with that (or fighting their kids over it) since people started having home computers.

Unfortunately I am not aware of any consumer-grade (in other words, affordable) routers that do what you ask. I’m not aware of any standard setting that will somehow throttle the internet speed.

But there are alternatives.

Read moreHow do I slow down my router at night?

Why doesn’t my machine’s IP address match what I’m told on the internet?

Using tools on my machine, I can see that my IP address is one thing (in my case, But when I go to an internet site that shows me my IP, it shows my something completely different. Which is right?

They both are.

Your machine really has only one IP address, but it isn’t necessarily the IP address that’s used to connect to the internet.

The IP address that appears really depends on who’s looking and from where.

Let me explain the who and where that I’m talking about.

Read moreWhy doesn’t my machine’s IP address match what I’m told on the internet?

What is DHCP?

What is DHCP?

DHCP stands for Dynamic Host Configuration Protocol.

I can hear you thinking, “Thanks a bunch, but … what’s that?”

In a nutshell, DHCP is all about the request that your computer makes and the response that it receives when assigning a “dynamic” IP address.

Let’s look at that a little more closely.

Read moreWhat is DHCP?

If I Let My Neighbor Share My WiFi, Can They See My Network Traffic?

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.

Read moreIf I Let My Neighbor Share My WiFi, Can They See My Network Traffic?

What Can People Tell from My IP Address?

What exactly can someone tell from your IP address and what can they do with it? Can they find personal details or my precise geographical location?

It’s typically very easy to find out your IP address or the IP address of someone with whom you are communicating somehow on the internet.

Unfortunately, many people believe that with an IP address, it’s possible to find out all sorts of information about the person at that connected computer.

That’s simply not the case.

Exactly how much it does expose about you specifically depends on your ISP and how their (and your) network is configured.

The very short answer? Not much.

Read moreWhat Can People Tell from My IP Address?

How Does NAT Work?


Regarding your article What’s the difference between a hub, a switch, and a router? your description of routers raised a question. When using NAT, how does the router know which local IP address should receive an incoming packet? Using your example network, suppose computer “A” sends out a packet to someone on the internet. But what if at the SAME time, computer “B” sends out a packet to the SAME someone?

Now, each local IP address (from computers “A” and “B”) both get translated to the same internet IP address (72.134.xx on your diagram) and then sent out to the same someone on the internet. That person then sends back responses for both computer “A” and computer “B” on the same internet IP address. The router receives these response packets, but how does the router know which packet goes to which computer? Both came in from the same place with the same destination internet IP address.

It turns out that NAT, or Network Address Translation, is actually a very simple concept; one that we rely on every day to share a single internet connection across multiple computers as well as to keep those computers safe from internet threats.

Simple in concept, maybe, but difficult – complex even – to explain.

But, I’ll give it a shot.

Read moreHow Does NAT Work?

Can I combine two internet connections to get a faster connection?

Can I merge two internet connections so that I have doubled bandwidth? I have a DSL connection as well as a separate EVDO connection. I want to know if it is possible to merge the internet connections so that the bandwidth speed would be added to each other, resulting in increased bandwidth.
Because this article was originally written a few years ago, the answer has actually changed from “mostly no” to “mostly yes, with a caveat”. There’s hardware now available – not even all that expensive – that will allow you to connect two internet connections to your local area network. But … there might be a catch. Depending on what it is you’re hoping to accomplish, you may be disappointed.

Read moreCan I combine two internet connections to get a faster connection?

How do I get wireless internet?

We have dial-up at our house and I’m sick of it. I can get on the internet from my iPod at the edge of my property, but I want internet on my desktop IN my house. What do I need to connect up?

I want to use this question to clear up a misconception that appears to be surprisingly common.

Wireless internet is not just “out there” to connect to. You need to take steps, whether it’s setting something up, paying for something, or at a minimum, asking for permission.

It’s definitely not the case that you can just grab a wireless card and suddenly be connected anywhere you want. The wireless capabilities of your computer are only half of what’s needed.

There are several approaches to getting a wireless internet connection.

Read moreHow do I get wireless internet?

What’s My IP Address?

As you probably already know your IP address is the “address” or logical (not physical) location of your computer or router connected to the internet.

There are plenty of sites that will tell you your IP address. In fact, any web site you visit can see it.

I’ll do the same, but also try to explain, a little, exactly what it is you’re seeing.

Read moreWhat’s My IP Address?

What is “Limited Connectivity” and how do I fix it?


I have recently started receiving “limited connectivity” messages at our vacation condo. Looking on the web I’ve found a jillion ways to fix this problem and can’t believe all the advertising. I’ve found that cycling the repeater that is in our condo will usually clear this problem. What causes it and what do I do when cycling the repeater doesn’t work?

“Limited connectivity” happens when your computer can connect to the network … but it can’t.

I know, that wasn’t very helpful. But it’s actually accurate. Your computer was able to connect the network in one way, but was unable to complete the next step.

Read moreWhat is “Limited Connectivity” and how do I fix it?

How Do I Connect My Desktop to the Nearby Wireless Internet WiFi Hotspot?

I have a desktop computer that is not hooked up to the internet, nor has been. There is a WiFi hot spot down the street; since it is free I would like to be able to connect to it. What do I need to buy and do to get up and connected to it?

You need two things to connect to that local hotspot. One you can probably buy at any computer store, but the other might be harder to come by.

Let me explain…

Read moreHow Do I Connect My Desktop to the Nearby Wireless Internet WiFi Hotspot?

Why Does My Home Network Only Work with One Computer at a Time?


The network consists of a cable modem, a hub/router, CAT5 cable in the walls, and two computers. If I disconnect one computer at the hub, the other one works. If I disconnect that one and connect only the other computer, it works. But, when I connect both neither works. I suspect a problem with the two computers getting the same address. Is this likely? How do I trouble shoot this kind of problem?

I suspect pretty much what you’ve indicated: a problem in the IP address assignment. But exactly what problem depends on a few details. Details we can look at.

Read moreWhy Does My Home Network Only Work with One Computer at a Time?

Why Does My Network Connection Drop Every so Often?


Why does my network connection drop every so often?

There are many possible reasons so I’ll focus a common one: confused network auto-speed detection. Most contemporary network cards, hubs, and routers attempt to automatically determine the speed of each network connection. Sometimes they get it wrong.

Most home and office networks run at either 10 or 100 megabits per second (mbs). Just how the network devices tell the difference varies from one device to the next. Most will also monitor the speed continuously just in case it changes. That means that if the device is going to make a mistake it could happen at any time. And that can look like anything from really poor network performance to a previously working network connection suddenly dropping.

Read moreWhy Does My Network Connection Drop Every so Often?