Many dedicated FTP clients and automation utilities have since been developed for desktops, servers, mobile devices, and hardware, and FTP has been incorporated into productivity applications such as HTML editors and file managers.Īn FTP client used to be commonly integrated in web browsers, where file servers are browsed with the URI prefix ' ftp://'. The first FTP client applications were command-line programs developed before operating systems had graphical user interfaces, and are still shipped with most Windows, Unix, and Linux operating systems.

For secure transmission that protects the username and password, and encrypts the content, FTP is often secured with SSL/TLS ( FTPS) or replaced with SSH File Transfer Protocol (SFTP). FTP users may authenticate themselves with a plain-text sign-in protocol, normally in the form of a username and password, but can connect anonymously if the server is configured to allow it. FTP is built on a client–server model architecture using separate control and data connections between the client and the server. SFTP - allowed: if SSH is allowed, not specifically supported/detected.įTPs implicit - not used/outdated: it is not supported.įTPs explicit - adjustments needed: as above.The File Transfer Protocol ( FTP) is a standard communication protocol used for the transfer of computer files from a server to a client on a computer network. SFTP - not used: it can be manually allowed by allowing port 115. Once the firewall allows the session for the data channel, the traffic will pass whether encrypted or not.įTP and TFTP are functioning through their corresponding session-helpers.ĭeleting these session-helpers may prevent the correct ports from being open. Secure data channel: requested by PROT command (not enabled by default by the above commands concerning the command channel). If FortiGate has no 'deep-inspection' enabled, it can not know these ports and allow the traffic.ĭeep-inspection is required in the policy, and proxy-profile must also be adjusted for scanning to find out these ports. The ports used for data (clientserver) are negotiated through this channel. Secure command channel: requested by AUTH TLS (explicit) or AUTH SSL (implicit) commands. Separate generic SSL session for data transfer using dynamic ports. 'Explicit FTP Proxy' does not work for FTPS prior to FortiOS 6.2.1 (for the same internal ID as above).ġ) FTPs-implicit (outdated) -the entire FTPS session is encrypted uses:

FortiGate can't differentiate based on the embedded signature of the sFTP from SSH.Ī custom signature is needed to block SSH but allow SFTP ( Technical Tip: How to block SSH but allow SFTP using the same TCP port 22).įTPs - FTP+Authentication (FTP over TLS or SSL extension of FTP protocol: uses :įortiOS support for FTPs is introduced starting with FortiOS 6.4 (and not supported in versions older than 6.4, for Mantis 532698). SFTP is not supported/detected by the FTP signature (564518). SFTP - Secure FTP (or 'FTP over SSH' extension of SSH protocol): uses SSH port 22 Nowadays SFTP should read 'sFTP' and refers to 'Secure FTP'. Protocol not used anymore (assigned Historic status by the IETF = not used anymore). SFTP - Simple FTP (RFC913): uses port 115. TFTP - Trivial File Transfer Protocol ( RFC 1350): uses UDP 69 tftp session-helper operates as above. FortiGate opens the session expectation accordingly). (FTP helper in FortiGate checks the port because the FTP command port is not encrypted. Passive: client tells the server which port to use for data. (default mode uses port20 not suitable if Firewall does not explicitly opens this port). Active: server tells the client the port to use for data. Technical terms are explained in relation to what firewall ports need to be open to allow the traffic.įTP - File Transfer Protocol: uses TCP port 21 for command and TCP port 20 for data transfer. It contains the basic mode of operation, differences, and explanations. This article describes the FTP suite of protocols (FTPs, sFTP, SFTP).

Ports used by ftp