Internet slows down

[Cucumberry]

I've had internet problems for a while now, but they've stayed pretty minor. However, lately I've noticed something really bizarre happening. When I download a file, it starts at a great speed, but subsequently slows down terribly.

I made a video for anybody who doesn't believe me or just wants to see for themselves. You can watch it here (sorry for the bad quality, blame Photobucket. It's legible enough in full screen). I tried to download a video from youtube, and it started at 1.5 MB/s, but slowed down all the way to 58 KB/s.

I have no idea what's happening, but I hate it. I'd be eternally grateful to whoever can help me resolve this.

Oh, I'm on a MacBook from 2008 by the way. It's got a 2.4 GHz processor and 4GB of RAM.

 

[ElDiabloConCaca]

Do you have a cable modem (as opposed to DSL, fiber, etc.)?

If so, a lot of cable internet providers advertise their internet speed as "10Mbit/sec" or something rather high, but in reality, they're implementing something that's typically called "speed boost."

What this does is for the first megabyte or five, you see the advertised speed (which is typically very fast). After those initial megabytes, the link is then slowed down to a much slower speed.

The reasoning behind this is that most internet users typically just surf web pages, which are usually no more than a few megabytes in size (and more often than not, less). So, your average user will always be seeing the super-fast advertised speeds, since the entire web page is downloaded in the first few super-fast megabytes, and they never receive enough data to cross the threshold into the slower speed.

Time-Warner does that here in Texas for some of their internet plans. This is usually advertised as an 8Mbit link speed, which you only see for the initial 20MB of data received over one link, and is then slowed down to just under 1Mbit for the remainder of the data being received -- most users will never cross the line into the slower speed, so no one throws up a fuss because they don't even know it's happening. You may want to check with your ISP and see if this is what's happening.

Does this happen across ALL computers at your house? Is this a new problem, or something that's always happened?