Samanathon.com

I’ve done quite a bit of networking throughout my computer career (although mostly home networking), and there’s some little tricks I’ve been using I figured I could share. The programs I’ll talk about here are really just for information gathering (the whys and what’s of what isn’t working) so they won’t fix anything on their own. But hopefully they should be able to narrow down any problem you may be having and make fixing your connection a little easier.

So with that said - and just so I’ve said it - a lot of this is going to be simplified to a really basic level. So no “that’s not exactly how it works!” or “that’s not what that does!” comments are necessary. I’m well aware.

Let’s Get Started

To access these, we need something that’s a blast from the past: the Command Prompt. It used to be everything was run from the command prompt. Now it’s just some sad vestige of DOS, that for some reason is still the only way to get some of this information, without having some 3rd party program.

So to get to a command prompt you can find it in your Windows Start bar (Start->Accessories->Command Prompt), but personally I hate searching through the menu for it. You may find it quicker to use the Windows Key+R to bring up run, then type in “cmd” (without the quotes). Hit “Enter” and voila, your own little Command Prompt.

So How Does This Help With Networking?

Let’s say you’re having trouble with your network; your PC can’t connect to any websites. Well if you type in “ipconfig” it’ll bring up most of your current network information (IP address, subnet mask, gateway) or it’ll tell you if it’s disconnected. You can also use ipconfig to get extended information (including your MAC address) by using “ipconfig /all”.

Ok, so you’ve checked your IP address, and that’s all looking good, but something still isn’t happening between your computer and the network. Time to trying pinging something. The “ping” command will send a basic set of packets to the target and post how long it took to get a reply from that target. For example, if you use “ping google.com” you’ll ping the Google host (basically saying “Hi there!”). Then the Google host will send back a reply (”Hello!”). Then you’ll get a readout as to how long it took (in milliseconds) for that whole exchange to happen. Ping will automatically do this 4 times, so you can get a very basic average as to how fast your connection is. Also if some of your pings time out, it’ll give you a loss rate (which means that the connection your on is faulty in some way).

*** Note from Saman: FYI, you can add the ” -t” switch to send packets indefinitely - or until you stop it! So you would type (without quotes): “ping google.com -t”. To stop pinging, hit CTRL+C ***

Now you’ve done that, but for some reason it all timed out. Maybe it gave you a “host cannot be reached error” of some kind. Time to see if you can find where the breakdown is. The command “tracert” can be used to trace the route a packet takes from your computer to the target. It’ll ping each target (each node along the way) until it reaches the target you picked. So you’re in a hotel, using their wireless (a situation I am all too aware of), and you can’t connect to any site. Your computer says you’re connected, and you have a local IP address, but no websites are loading. So you run “tracert google.com” and start watching what jumps it takes. Well, it only takes one jump, to your gateway (the wireless network hub) and dies. Well now you know that the problem is with them. Since you can’t get any pings outside their network, you can call them up and ask what’s going on.

So some of these may have been familiar. In fact if you’ve ever talked to a help desk drone about your non-function connection, you may have been asked to run some of these. Hopefully with this introduction you’ve gotten a little better understanding of what each one does, and why they’re so useful.

And now you can stop asking me why I run “ipconfig” so often.

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