FTP Sequence Diagrams
Here we explore the sequence of interactions in a typical FTP (File Transfer Protocol) session. Individual sequence diagrams for interactions on Port 20 and 21 are also included.
The complete sequence diagram can be divided into the following steps:
- DNS Query to obtain the IP address for the FTP Server
- FTP Telnet connection setup and login. (USER and PASS commands)
- Obtaining a directory listing (PORT and LIST command)
- Changing directory (CWD command)
- Downloading a file using FTP get (PORT and RETR command)