Understanding upload speeds

Our Internet service upload speed is “up to” 1Mbps. There are packages available that boast up to 2 and 5 Mbps for $120 and $240 per year respectively.

We do a lot of uploading for work, so we’re trying to figure out whether the upgrade is worth it.
I have a couple problems figuring it out. First, most of the calculators are understandably vague about overhead. But does overhead relate to the bandwith? That is, if I put in a somewhat arbitrary 50 percent and a 100 MB file, is it legitimate to compare the result for all three speeds? Or would a 1 Mbps connection have a much harder time than the 5 Mbps connection managing that much overhead? Oh, and any suggestions as to what to use for overhead?

The other issue is that the calculators I’ve found relate to common download speeds and skip over the 5 Mbps speed. Is there a simple Excel formula I can use? Or a site that includes the speed?



Overhead is simply the “metadata” that is required to transmit a file.
So, if you need to transmit exactly 1,000,000 bytes, the total amount that has to be sent is 1,000,000 + the overhead (handshaking, error correction, packet headers, etc). This is independent of the upload speed, and shouldn’t be more than a few percent (for large files).

Thanks. So if we’re concerned with 100 MB+ files, using 2 or 3 percent should be fine?

And do I then have this math correct:

100 MB file is 800 Mb.
Add 3 percent for overhead and it’s about 825 Mb worth of data.
Divide that by 1.024, 2.048 and 5.120 to give me approximate upload times in seconds (805, 402, 161).

Yes, that’s a good approximation.
But, as in all things - YMMV!

Overhead is not the only issue. The bandwidth allowed on the remote site is also relevant, as is just distance traveled, as signals degrade over time, reducing the maximum throughput. This is the biggest reason that mileage may vary.

I’d check on the actual speeds (on a site like dslreports) and base your choice off that. You may need to go with a higher speed tier to get more than a few hundred Kbps up. Remember, “up to” is the maximum you can get, and has no legal or practical connection to your actual speeds.

Also, remember that downloads have a certain amount of upload overhead (in the form of acknowledgements and such).

Gotcha, thanks.

I put the “up to” in scare quotes as a nod that it’s a maximum under optimal conditions, and get that there are a lot more factors than allowed upload speed.

But if I’m not mistaken, you’re saying that in general, upload speeds and overhead are comparable across speeds. That is, congestion, noise on the line, etc. will drop each tier the same amount (give or take).

Choosing between packages is a bit moot now–gave them a call to ask about pricing and they bumped me from the 1up/15down to the 5up/30down plan with just $3.00 per month. Pays to call!