I had forgotten about modem compression. Back in the BBS days when you had to upload files to get new files, you usually had a ratio (20 bytes download for every byte you uploaded). I would always use the PKZIP no compression option for the archive to upload because Z-Modem would take care of compression over the wire. So I didn't burn my daily time limit by uploading a large file and I got more credit for my download ratios.
Another download ratio trick was to use a file transfer client like Leech Modem, an XMODEM-compatible client that would, after downloading the final data block, tell the server the file transfer failed so it wouldn’t count against your download limit.
That sounds like it can be fooled by making a zip bomb that will compress down to a few KB (by the modem), but will be many MB uncompressed. Sounds great for your ratio, and will upload in a few seconds.
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I had forgotten about modem compression. Back in the BBS days when you had to upload files to get new files, you usually had a ratio (20 bytes download for every byte you uploaded). I would always use the PKZIP no compression option for the archive to upload because Z-Modem would take care of compression over the wire. So I didn't burn my daily time limit by uploading a large file and I got more credit for my download ratios.
I was a silly kid.
That's really clever and likely would have gone unnoticed by a lot of sysops!
Another download ratio trick was to use a file transfer client like Leech Modem, an XMODEM-compatible client that would, after downloading the final data block, tell the server the file transfer failed so it wouldn’t count against your download limit.
https://en.m.wikipedia.org/wiki/LeechModem
That's awesome! I totally would have used that as a young punk if I knew about it.
That sounds like it can be fooled by making a zip bomb that will compress down to a few KB (by the modem), but will be many MB uncompressed. Sounds great for your ratio, and will upload in a few seconds.