I’m not saying is not a valid solution, however I recommend not using it.
Why? As you can read [url]http://en.wikipedia.org/wiki/File_eXchange_Protocol[/url] most FTP servers will have this disabled, due the high bounce risk.
On the other side, IS is the client and does only have control over the “start” and “end” commands, would not be aware of status (percentege of transfer), transmission speed, and of course cannot be used to reconnect, ressume etc, so that’s all.
Remote FTP server needs to have all ports (or a range of high-ports for PASV defined) and enabled on the firewall, same for Source FTP server. Behind NAT this usually fails.
FXP is great! I love that protocol and used for years, however I do not recommnd it due the complex setup in today’s enterprise firewalls.
If you talk about public FTP sites, then go for it.
Still your POST give a good alternative in case this is a must, and indeed it might be the only solution 
#Integration-Server-and-ESB#webMethods#webmethods-Protocol-and-Transport