I frequently do website development live over an FTP connection. That is to say, I use a code editor with a built in FTP window and push/pull files to work on them, upload the changes, etc. This is mostly because it's unreasonable to try to create a local development server, and I use too many computers for that to be practical anyway without a lot of work.
My trouble is, the internet connection at our home is not exactly... stable. It's fast and mostly reliable, but it has a tendancy to glitch far more frequently than any other connection I've worked on (it's wireless DSL) and as a result, dropped connections are far too frequent. (It's about as reliable as AT&T is with phone calls in that regard.) When working with FTP, I find that if it drops the connection mid-file transfer, it can be difficult to recover. First of all, when the connection is dropped, it saves a blank file to the server (how is this helpful?) breaking the page I was working on completely, and the icing on the cake is that depending on the timing, vsftpd will get itself stuck in a timeout and I have to SSH in and restart it before I can access that file again.
This process alone has only been beneficial because it's taught me to build up some data protection techniques clientside, to prevent the server from eating my recent changes if the dropped connection happens to hang or crash my client. Overall though, it's a pretty failed situation, and I'm surprised I get any work done at all.
Long, long context, I know, but my question is this: Is there a file transfer protocol that is designed to handle "flakey" connections like mine? I'd imagine that, for example, trying to transfer files over a 3G tethered connection would yield the same results, especially while traveling. It seems like FTP and SFTP both rely on a persistant connection, and can deal with dropped packets but not the loss of the entire socket through a reconnect. It seems to me like a file transfer daemon should be able to store the state of the user interacting with it, and thus detect failed transfers and be ready to "resume" if the user reconnects in a reasonable amount of time.
Thanks if anyone knows anything. I'm seriously considering trying to write such a protocol myself (I've had a lot of success coding the ajax on my page to handle faulty connections, for example) but I don't want to dive in if there's already a solution available.