EERP response in the same session

We have a partner that said that our EERP response are not being sent in the same session, and it causes an error in their side. Is it possible to configure the EERP in the same session?




this must be a missunderstanding of the OFTP2 protocol or the question is missleading but there is no sync mode in the OFTP2 protocol.

Please use AS2/AS4 for sync responses.


Regarding RFC5024 [page 30 and 31] - A Response Command must be sent from the location performing the final processing or distribution of the data to the originator. The Response is mandatory and may be sent in the same or in any subsequent session.

So it is possible to send the response in the same session. Doesn't Mendelson have this option?


in OFTP2 the postprocessing (decryption, verification of signature) on the receivers side is done after the data has been received. If this takes a long time or the server is under heavy load the initiator may have closed the session already before the EERP is available and sent back. That is ment by "and may be sent in the same or in any subsequent session", the secion you referred.
There won't be any OFTP2 software out that could ensure synchronous transfer (even if routing would be impossible then..another point). The transfer might be sync but only if the timing allows this. But this is not what is called "sync transmission" as this could be be assured. OFTP2 is an asynchronous protocol.

Please ask your partner again if this is really what he is looking for, looks like a missunderstanding.



In OFTP2 there is no way to keep a session open for infinite time (like it is possible in AS2 and sync transfer). The reason is that there is a timeout of 45s between the OFTP2 protocol messages and there does not exist a "NOP" like in passive mode of FTP. Means if there is nothing to do the session HAS to be closed. It is impossible to wait for the other system to perform some action. It is possible to swap sender and receiver one time (cd, change direction: push-pull) but it is not allowed to do this more than one time which would result in a session close after about 1-2 minutes if there is no waiting EERP because the other system is still processing the decryption and the signature verification.

If the other OFTP2 product does not follow the OFTP2 protocol in the way you describe you could simply poll the other system time based (see connection settings). Every poll process will send EERPs and messages for this system and pick up EERPs for your system from the remote system. That should solve your issue.This is also the standard process for several huge vendors that are not willing to connect to all their customers - they are just putting all messages and EERPs onto their system, perform no outbound connection and wait for the time based poll.This way they don't have to deal with the firewall problems etc of their customers.

Because you mentioned the name of the other OFTP2 product - we have several customers that exchange data via mendelson OFTP2 with partners that have licensed the product you mentioned - without problems. I still think that there is a missunderstanding in the "sync OFTP2" requirement.


I know that is a deficiency of the other system, but I would like to know if there is a way to try to send it in the same session at all. I mean, to make the system keep the connection opened for 1-3 minutes to try to send the EERP in the same session.

Nowadays the system works like this:

"Other Software" establish a connection to Mendelson for sending messages -> via OFTP2 -> Mendelson receive message and decrypt, uncompress and remove signing -> Mendelson closes the connection -> "Other Software" receives protocol that we have sent the message to you -> Mendelson establish the connection and send the EERP -> "Other Software" do NOT get any more information as LONG as the connection is closed -> "Other Software" establish another connection (for example: for sending another message) and receive the EERP for the old message BUT this EERP is not in the same Workflow.

They need to have a flow like described below, that I think to be a way that can be done keeping the connection open for 1 up to 3 minutes, or until the finish to send the EERP:

"Other Software" establish a connection to Mendelson and sending messages -> via OFTP2 -> Mendelson receive message and decrypt, uncompress and remove signing -> Mendelson sending EERP -> Mendelson close the connection -> "Other Software" receive protocol that we have send the message -> "Other Software" has now all information for this workflow in ONE protocol because this transfer was in one session

I know that is a weird requirement but seems easy to fix, there is any way to do that by changing any parameter???


In our inhouse tests the EERP is (nearly) always sent in the same session. Perhaps this is an issue of your processing speed or the size of the messages - anyway this is nothing to rely on, OFTP2 has no sync option and mainly it is luck if the EERP comes back in the same session or not. It would be possible to analyse what happens by checking the protocol message but please understand that we cannot do this for you in the community version. In your case please have a look at the RFC (which is more a processing instruction manual than a RFC in OFTP2). If you enable the message log in the mendelson OFTP2 settings you will see very detailled what messages with which content are sent and received.
Anyway if you use some more advanced OFTP2 features like routing (which is very common for huge companies) there are other OFTP2 stations involved in every transaction and a sync OFTP2 is impossible even if you keep up the connections 1-3 minutes, sometimes it takes half an hour to get an EERP/NERP.