On 2013/07/13 6:56, Mouse wrote:
The SSH File Transfer Protocol provides secure file transfer functionality over any reliable data stream.Well...it, combined with the rest of ssh, does; sftp itself doesn't provide any significant level of security, depending on lower layers for that. But, really, it provides a lot more than file transfer; it's really a remote filesystem access protocol, misnamed as a file transfer protocol. If you really want a file transfer protocol, I'd suggest using a slight mutation of FTP (using ssh channels rather than TCP connections). But, apparently, people prefer a remote filesystem access protocol, even a misnamed one.
Funny we should arrive here. That was one of the things VanDyke was considering in the time frame between SFTP advent as a product and the publishing of the initial draft. We may have even brought it up in an ietf meeting. From a technical view point, this is still somewhat interesting to me; one of the difficulties with SFTP (as speced from draft 0 onwards) is the request/response nature of moving data. A protocol (like FTP) that just said "send me the whole file as fast as you can" would probably be a lot harder to mess up performance wise than SFTP, where it is necessary to issue multiple overlapping read requests with carefully tuned max-packet, read size, and channel window in order to get reasonably good performance. Thanks, Joseph