I had a very annoying experience when I started to download a large (700 MB) file from my home server to my Galaxy Tab. I used the SFTP and the SCP protocols at first but the download speed never went above 56 KB/s (on a fast server, almost perfect 802.11g network and the galaxy tab more or less ontop of the wireless router).
However, when I gave up and started a proper FTP server instead (vsftp in this case; it's an OpenSuse server) I immediately got download speeds of approx 2000 KB/s.
Why is that? Anyone has a an idea?
Additional info: I tried SCP to the same server from another client (Fedora in this case) at home and then the transfer speed were quite good (13 MB/s), well in line with the network capacity. It doesn't seem to be a misconfigured server.
SFTP and SCP extremely slow but FTP fast?Re: SFTP and SCP extremely slow but FTP fast?SFTP is the slowest because of encryption overhead (look at CPU usage it should be high). SCP is quite better and FTP or FTPS is quite fast.
Re: SFTP and SCP extremely slow but FTP fast?Thanks for the overview; makes a lot of sense.
But it doesn't explain the difference I got when using AndFTP: SFTP, SCP approx 56 KB/s (yes, SCP were slightly faster, a few kB/s) FTP approx 2000 kB/s. That's almost a factor 40. Same file, same network (wireless at home), same server. Is there any network tuning I can do on the Galaxy Tab (Android 2.2) that would affect this? Imediate update: After I wrote the stuff above, I checked the CPU-load on the Tab when downloading 1) SFTP (99%), approx 120 kB/s 2) FTP (85%), approx 1800 kB/s You were quite right all along The decryption is too heavy work for the cpu. Thanks! Re: SFTP and SCP extremely slow but FTP fast?We're trying to find some workaround by allowing lower encryption. But new devices with improved CPU should make it faster.
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