File Transfer Protocol: Transmission

Packet switching is a network communications method that groups all transmitted data, irrespective of content, type, or structure into suitably-sized blocks, called packets. The network over which packets are transmitted is a shared network that routes each packet independently from all others and allocates transmission resources as needed. Principal goals of packet switching are to optimize utilization of available link capacity and to increase robustness of communication.

Network resources are managed by statistical multiplexing or dynamic bandwidth allocation in which a physical communication channel is effectively divided into an arbitrary number of logical variable-bit-rate channels or data streams. Each logical stream consists of a sequence of packets, which normally are forwarded by a network node asynchronously in a first-in, first-out fashion. Alternatively, the packets may be forwarded according to some scheduling discipline for fair queuing or for differentiated or guaranteed quality of service. In case of a shared physical medium, the packets may be delivered according to some packet-mode multiple access scheme. When traversing network nodes, packets are buffered and queued, resulting in variable delay and throughput, depending on the traffic load in the network.

Packet switching contrasts with another principal networking paradigm, circuit switching, a method which sets up a specific circuit with a limited number dedicated connection of constant bit rate and constant delay between nodes for exclusive use during the communication session.

Packet mode (or packet-oriented, packet-based) communication may be utilized with or without intermediate forwarding nodes (packet switches).

Simple File Transfer Protocol, as defined by RFC 913, was proposed as an (unsecured) file transfer protocol with a level of complexity intermediate between TFTP and FTP.

It was never widely accepted on the Internet, and is now assigned Historic status by the IETF.

It is sometimes confused with SSH file transfer protocol, a secured file transfer protocol.

It runs through port 115, and often receives the acronym of SFTP. It has a command set of 11 commands and support three types of data transmission: ASCII, BINARY and CONTINUOUS. For systems which have "WORD SIZE" which are multiples of 8 bits, the implementation of BINARY and CONTINUOUS is the same.

The protocol supports the following:

1. User id based login (User-id/Password combination)
2. Hierarchical folders
3. File Management (Rename, Delete, Upload, Download, Download with overwrite, Download with append)

The protocol does not support random access inside a file (required for resuming interrupted transfers).

SFTP may refer to:

Relating to file transfer:

* SSH file transfer protocol, a network protocol designed by the IETF to provide secure file transfer and manipulation facilities over the secure shell (SSH) protocol. This is typically meant in context of file transfer.
* FTP over SSH, the practice of running an FTP session over SSH, sometimes called Secure FTP. Rarely used, because FTP's normal 2-channel nature makes such tunneling hard.
* Simple File Transfer Protocol, an unsecured and rarely-used file transfer protocol from the early days of the Internet.
* Serial File Transfer Protocol, a protocol used to transfer files between a PC and an embedded device using RS-232 or similar serial protocols.

SFTP may also refer to:

* Screened fully-shielded twisted pair, a kind of network cable, in contrast to FTP and STP
* Science for the People, a U.S. left-wing organization and magazine
* Six Flags Theme Parks, chain of amusement parks and theme parks.