questions

Can you clarify the exact the metrics here a little? I'm guessing you mean that your connection is 64kbps. But, I'm not sure if you mean that your download rate is 7kbps or 7KB/sec. There's a big difference!

Connections are usually advertised and sold in bit rates, like a 56kbps (kilo bits per second) dialup. But, download tools often report download rates in KB (kilo bytes per second). IE reports download speeds in KB. The difference is that there are 8 bits in a byte.

Leaving to the side for a moment limitations in connection technology that leaves you with something less than 56kpbs usable speed on today's standard dialup, and forgetting overhead and all else, just to keep it simple...

A 56kbps connection will yield at best 7KB/sec downloads. ( 56 divided by 8 ). Your 64kbps connection is a little faster, but not counting compression, I doubt with overhead you'll do too much better than 7KB/sec either.

 

It sounds like you are still mixing the metrics (bits versus bytes)...

Your ISDN connection is 64kbps or 64000bps. The "b" is "bits" not bytes.

Your download speeds are 7500 bytes/second. Bytes are 8 times bigger than bits. So, 7500 bytes/second is equal to 60000bps. ( 7500 * 8 ) That is almost at the theoretical limit of your ISDN lines speed.

If you see an Internet Explorer download window (like in the image below) that says 7.5KB/sec then you are getting full speed from your 64kbps ISDN line.

 

Hi Larry,

I'm not sure what type of connection you are talking about there, or what type of downloads either. For data that is already compressed (ZIP or EXE files) and which can't gain speed through further compression, you can only transfer over any connection media at the fastest rate of that media.

A 56kbps dialup would yield a maximum rate (when it can't further compress the data being downloaded) of approx 7KB/sec on its best day.

Now, true if you are downloading text or html and it can be compressed, then you will see higher download rates than this.

 

I've been with you all along. So, you do now understand that 8.0KB/sec (notice the capital letters) is the maximum speed for a 64kbps (lower case) circuit, right?

No, there really isn't any way to get faster downloads of already compressed "large files". The thing complicating this is that compression of files can really change what your download rate looks like. If you have compression enabled and you download a large text-only file, (or any file with easily compressible data in it), the compression will crunch that file down significantly, on-the-fly, as it moves over the connection so that the download rate you'll see could be huge... 16KB/sec would not be unusual, in fact it could be even faster.

However, if you are downloading a compressed file (such as .ZIP, most .EXEs, certain image types, etc. all of which are already compressed), a compression technique will not help... A file that is already compressed will come down at the maximum throughput of your connection type. In your case, 8KB/sec.

All those accelerator tools do is make your connection as efficient as possible. They compress data. They multi-thread the data (trying to open multiple download paths to the download server). They cache files that are reused so you don't have to download them again. But, they do not give you more download bandwidth then the capacity of the line you have installed. If you really want a faster download rate for large compressed files, you must get a faster connection. (Again, other than the tricks mentioned above, the true download rate for such files is not increased.)

Yes, that is correct.

This does not mean that there aren't some benefits to these download accelerators. There is really something good to be said for making your connection as efficient as possible, but if your goal is being about to download things like: software install or patch kits (.EXEs) or multiple megabyte ZIP files, these tools won't make the kind of speed difference you seem to want.

 

More often than not the compression on modern modems is done right in the hardware, or if not there then in the protocol of the connection between your PC and where you are connected. The two ends agree upon the settings they'll use including any compression techniques. (You may not be able to do anything about this directly.)

As to what compression is in general? First, here's a page over at HowStuffWorks:

How File Compression Works

Have you ever used WinZIP or any other archive tool? If you have WinZIP installed, you can play around with large text files, or ".BMP" image files which are very compressible, and see just how much smaller they become if you ZIP them. It can be a dramatic size reduction. 10 to 1 is not unreasonable, even more sometimes.

I can send you a private message using the board's IM feature with two download links that you can do a test with to see if compression is already helping you. One is for a large (1MB) file that is already compressed, and the other is to a file the same size that is simple uncompressed text. If compression is already configured on your connection the text file will download much faster than the already compressed one.

Let me know if you want to test this and I'll send you the links.