Terminology

While using this documentation, you will encounter a set of concepts and terms from the secure file transfer domain. You may already know and understand some of the terms, while the meaning for others might be unclear.

This section tries to describe the meaning and usage of these special concepts and terms.

account

The set of all configurations required to authenticate and authorize a client session. Examples of data stored in an account: user name, accepted credentials, home folder, ability to create missing home folders, list of shared folders, etc. The account configuration can be stored by the operating system or can be defined by SFTPPlus.

application account

An account for which the configuration is entirely provided by SFTPPlus.

client

A remote party initiating connections to the server and requesting file management operations.

configuration file

A file on the local file system used for storing configurations for the server or for a specific service.

configuration option

A distinct entry inside a configuration file describing server behaviour.

configuration section

A group of related options inside the configuration file. For example, the configuration file can define options for multiple services, and the set of all options related to a specific service are grouped inside a configuration section.

credentials

A pair of user name / secret values used for authorizing a client session. The secret can be a password, an SSH key, an SSL private key/certificate, or it can take other forms.

FTP

A standard network protocol used to transfer files from one host to another over a TCP-based network, such as the Internet or an internal LAN. For transferring a file, an FTP session requires two separate TCP connections, one for the commands and another one for the data transfer. This can complicate the setup of firewalls or network monitoring tools.

FTPS Explicit (AUTH TLS/SSL)

In explicit mode, the FTPS client must explicitly request security from the FTPS server, and then step up to use a mutually agreed encryption method.

FTPS Implicit

In implicit mode, the FTPS client is immediately expected to challenge the FTPS server with a TLS/SSL ClientHello message. If such a message is not received by the FTPS server, the server should drop the connection.

location

This refers to a folder that the software will either watch for new files, in the case of client use, or will put new files in the case of server use. These are completely configurable and can include local or remote folders.

Managed File Transfer (MFT)

This refers to software or a service that manages the secure transfer of data from one computer to another through a network (e.g., the Internet). MFT software is marketed to corporate enterprises as an alternative to using ad-hoc file transfer solutions such as FTP, HTTP, and others. MFT suites are often characterized by functionality for multiple protocols, encryption, automation, auditability, and integration.

operating system service

This is a long-running background OS process that doesn’t interact with the user through keyboard, mouse, or monitor. On Unix these services are also called daemons, while on Windows they are called Windows services.

os account

An account based on configuration provided by the operating system. The operating system can provide a set of information for the account, e.g. accepted password or home folder path. The configuration for an OS account can be extended with custom values provided by SFTPPlus.

process

The operating system process under which SFTPPlus is executed.

protocol

The rules defining how client and server interact for performing file transfer operations.

server

The sum of all services interacting between them or with external clients in order to perform file management operations.

service

A component of the server specialized in performing a well-defined set of operations. For example, the FTP service will perform all operations using the FTP transfer protocol. The authentication and authorization services provide all operations required by other services in order to authenticate remote clients.

This should not be confused with the operating system services, known as daemons in Unix/Linux or Windows services.

session

The sum of all file transfer operations starting with client authentication and ending with client disconnection.

SFTP

A network protocol designed to provide secure file transfer and manipulation facilities over an SSH transport and session layer. In contrast with the FTP protocol, SFTP uses the same connection for command and data transfers. It provides low-level file handling commands such as: open file, read section from file, close. On the other hand, FTP only provides a single RETR command which does all low-level file management.

transfer operation

A single file management command taking place inside a client session. For example, listing the content of a folder is one transfer operation, while downloading the content of a file is another one.

username

A unique identifier used during the authorization process for a client session. The user name is the key used for validating credentials and retrieving information for an account.