There are some additional RFCs relating to the FTP protocol.
The base specification is RFC 959 and is dated October 1985. This is in contrast to today’s environment where there may be an intermediary (Firewall, NAT device, etc.) responsible for sending the packets to and from a host on a private network. Additionally, it was designed to operate over communication channels where packets travel directly to their destination. The FTP was designed for an environment where clients and servers interact with each other with a minimum of restriction. FTP was designed with a great deal of flexibility so it could be used on non-TCP/IP networks and also have the capability to exchange files with a broad variety of machines. The File Transfer Protocol (FTP) has been around since the 1970’s and was one of the first efforts to create a standard means of exchanging files over a TCP/IP network.
We won’t cover the specifics of FTP client or FTP server configuration. In other words, we are only interested in how the FTP protocol makes connections and how those connections relate to each other. It must be noted that in this article we will only look at the FTP protocol from the point of view of connectivity. In this article we’ll look at the following issues: If network and firewall administrators understood how the FTP protocol works, they would be able to easily solve the FTP related problems they encounter. One of the questions most commonly asked when dealing with firewalls, routers and other Internet connectivity devices is why a particular FTP client or server configuration isn’t working. The FTP (File Transfer Protocol) protocol is one of the most popular, but also the most misunderstood protocols.