Traffix - the Easy Way to Monitor Your Mac's Internet Bandwidth Consumption

Ever since I heard that Comcast (my Internet Provider) was going to start instituting a hard bandwidth cap, I've been considering finding a bandwidth monitor so I'll know how close I am to that cap (and thus how close I am to losing my Internet access!). I've not been looking too hard, or too often, but it's been in the back of my mind.

Tonight, as I was browsing new Mac software releases, I stumbled upon a program called Traffix that is just what I need. Traffix monitors the amount of data sent from my computer to my cable modem, and from the cable modem to my computer. That number is the total amount of "bandwidth" I use.

Comcast has decreed that no user can use more than 250 GB of bandwidth in a month. Anyone over that, while not a guarantee, runs the risk of losing their Comcast account.

Now, 250 GB is actually a pretty large number. How large? Let's say you're the type of person who likes downloading movies off the Internet. A lot of DVD rips you'll find on the Internet are 700 MB. If you downloaded five movies every day of the month, you would have only used up 102 Gigabytes. That means you wouldn't even be halfway to your limit!

So, let's add in some music. Everyone likes music, right? So let's say you're big into file sharing, or maybe you belong to a service like Rhapsody, which lets you download music to hard drive for listening whenever you want. If you assume that an album of music is roughly an hour long, and that music has been encoded to the standard 128 kbps bitrate, then each album is roughly 60 MB in size. So let's say you download ten albums, every day of the month. You've only downloaded around 18 more Gigabytes!

Add that to all the movies you've downloaded and you're still not even halfway to your limit.

Put it this way: 250 Gigabytes is a huge number. And as Comcast says, most people aren't going to come anywhere near it. In fact, Comcast estimates that the average amount of bandwidth used is around 5 Gigabytes per month. That would be a person who pretty much browses the Internet and checks their email (and not much else), but it's a good starting point.

However, just because you aren't downloading (or uploading) a lot doesn't mean others are. If you're in a household with multiple computer users, or multiple computers all sharing a single connection, then it is entirely possible that you might be pushing your bandwidth limit. But I still find it unlikely.

Fact is, most people won't even need a bandwidth monitor, but if you have Netflix or a similar service that allows you to rent movies and watch them on your computer (both Amazon and iTunes do this), then you're dealing with larger numbers. Now, you're still (probably) not in any risk of what Comcast considers bandwidth "abuse," but better safe than sorry, I say.

Which brings us back to Traffix.

Using Traffix couldn't be easier. Turn it on; wait a couple seconds. It's checking your router or cable modem in order to see how much total bandwidth has been used. The first time you use Traffix, it will show a total of zero, but from this point (even if you don't run Traffix for a few days), it will give you an up-to-the-minute update of where you stand.

Based on what you've downloaded "so far," Traffix is able to estimate how much bandwidth you'll use for the entire month. Obviously if, immediately after the first time you launch Traffix, you download a huge file, Traffix will wildly overestimate your use. So my recommendation is to launch Traffix so it knows where you stand, then wait a few days. At that point, Traffix will have a few days worth of computer use to look at, and its estimate will be more valid.

In my mind, Traffix is a perfect tool. It doesn't install any daemons on your computer, so there isn't any "extra" software running. It simply checks with your router or cable modem, and presents what it's told. Then it makes its estimates based on those real numbers. The more time you give it, the more accurate it will be.

Traffix is available for Mac OS X Leopard (10.5), and is completely free.