fsp:

[1] File Service Protocol (FSP) Home Page (Radim Kolar, hsn@sanatana.dharma 著, 2007-03-06 08:06:38 +09:00 版) <http://fsp.sourceforge.net/>

[2] File Service Protocol (FSP) Home Page (Radim Kolar, hsn@sanatana.localdomain 著, 2014-09-10 02:59:43 +09:00 版) <http://fsp.sourceforge.net/index.html>

FSP stands for File Service Protocol. It is a very lightweight UDP based protocol for transferring files. FSP has many benefits over FTP, mainly for running anonymous archives. FSP protocol is valuable in all kinds of environments because it is one of the only TCP/IP protocols that is not aggressive about bandwidth, while still being highly fault tolerant.

[3] FILE SERVICE PROTOCOL VERSION 2 OFFICIAL PROTOCOL DEFINITION FSP v2 (2009-10-02 05:07:45 +09:00 版) <http://fsp.sourceforge.net/doc/PROTOCOL.txt>

[4] (2009-10-02 05:07:45 +09:00 版) <http://fsp.sourceforge.net/doc/PROTOCOL.txt>

Uniform resource locator format for FSP v2 protocol is:
fsp://password@hostname:port/directory/filename.ext
If port is omitted FSP standard port 21 is used, if password
part is omitted no password is sent. If no password is used URL must
not contain @ character before hostname. FSP URL do not have query
and anchor parts.