Why is SSH2 SFTP so much slower than FTP and FTPS?
Well, as I know, the reason for the discrepancy is that the SSH2 protocol has a lot of extra packets and encryption that FTP does not have to worry about. Besides, if we are talking about the scheduled sftp then it seems to me that turboftp client can be pretty useful and reliable for you so check them too.
It is important to understand is that SFTP will almost always be significantly slower than FTP or FTPS (usually by several orders of magnitude). The reason for the difference is that there is a lot of additional packet, encryption and handshaking overhead inherent in the SSH2 protocol that FTP doesn’t have to worry about. FTP is a very lean and comparatively simple protocol with almost no data transfer overhead and was specifically designed for transferring files quickly. Encryption will slow FTP down but not nearly to the level of SFTP. SFTP runs over SSH2 and is much more susceptible to network latency and client and server machine resource constraints. This increased susceptibility is due to the extra data handshaking involved with every packet sent between the client and server and with the additional complexity inherent in decoding an SSH2 packet. SSH2 was designed as a replacement for Telnet and other insecure remote shells, not for very high speed communications. The flexibility
