PeSIT first started operations in 1986, and to date at least seven different companies have developed the protocol.

PeSIT is available for a wide range of hardware including :

The ISO file transfer protocol, FTAM, could have met these requirements had its production process been sufficiently rapid to guarantee that the banking community would have access to FTAM products at a date compatible with the SIT project schedule. Since this was not the case, the banking profession therefore decided in 1985 to define a file transfer protocol for connecting to the SIT network.The result is PeSIT.
This protocol is based on the same philosophy as FTAM (integration in the ISO model, virtual file model etc.), and the PeSIT service (interface with the protocol user) is identical to the FTAM service. However, PeSIT offers only a subset of the planned functions of FTAM.


Les premières implémentations de PeSIT ont vu le jour en 1986 et à ce jour au moins 7 sociétés différentes ont effectué un développement du protocole. PeSIT est disponible sur une large gamme de matériel incluant :

At present, PeSIT has spread far beyond the banking profession. PeSIT is the only tried-and-tested protocol to allow dialoguing between the most commonly used transfer monitors employed in the French market.
PeSIT today exists in four operating profiles :


Four versions of PESIT have been defined, allowing it to operate in the following environments :

In each case, the protocol is identical; only the interface with the lower layers is different. This interface is defined in the PESIT technical specifications.


PeSIT is a file transfer protocol which allows the writing and reading of files between one computer and another; using a connection established over a telecommunications link (specialised connection, public network, local area network).

In order to avoid differences between the file management systems internal to each computer, PeSIT uses the "virtual file" concept, which provides a common file organisation model suitable for all computers.
Each PeSIT user manages translations between real computer files and the virtual files transferred by the protocol.
To comply with the terminology adopted by international standards, distinction is made between :

The PeSIT Technical specifications describe both the PeSIT service and the PeSIT protocol.


Remote file-writing :

This function allows a PESIT user to transfer the contents of a file towards another PESIT user. To this end, the sender must first set up a logical connection with the remote party. The user setting up the call is known as the "Caller"; the remote user is called the "Server". In this case, the file (data) transfer occurs between the Caller/sender and the Server/receiver.

Remote file-reading :

This function allows a PESIT user to request another PESIT user to transfer the contents of a file. To this end, the user wanting to receive the file (the "Caller") must first set up a logical connection with the remote user the "Server"). In this case, the file (data) transfer takes place between the Server/sender and the Caller/receiver.

Setting checkpoints :

This function allows the file sender to insert indicators, known as checkpoints, numbered sequentially, in the course of the transfer. The party receiving the data can acknowledge these points, which signifies that he has correctly received and stored the data issued up to this point. This mechanism ensures that in the event of an error, a transfer can be restarted from a point other than the top of the file.

Restarting a transfer :

This function allows the caller to restart a prematurely interrupted transfer. Restarting is possible whether the transfer is performing a read or a write, but it is always decided by the caller. Which checkpoint is used for restarting the transfer is decided by the party receiving the file.

Resynch during transfer :

This function allows a user to request the remote party to restart the transfer from an earlier checkpoint if a fault occurred during the data transfer. Unlike restarting - which occurs after interruption of the transfer (accompanied by closing and deactivation of the file) - resynch takes place during the transfer and the file remains open and active.

Suspended transfer :

This function allows a user to interrupt a transfer (that is, close and deselect the file in question) in order to use the current connection for running a higher-priority transfer. The suspended transfer will afterwards be processed under the restart procedure.

Transfer protection :

This function allows PESIT users to implement mechanisms offering various functions such as :

Data compression :

This function allows PESIT users to employ data compression on transmitted files, in order to reduce the transfer volume.

Error checking :

This function employs an error-detection polynomial associated with each message in the PeSIT protocol, to ensure that messages are not altered by transmission onto unreliable mediums.


This page is for everything relating to PeSIT protocol : documentations, software using this protocol... Should you know some other links, you can mail them.


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EDITH is a monitor designed to handle file transfer,multiple protocols, simultaneous multiple transfers, multiple networks X25 X32 RNIS TCP/IP. EDITH takes charge of all transfers automatically.