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Imported from previous forum

[ original email was from Maxim Volkonovsky - maxwolf@cma.ru ]
Does FIX specify the required number of messages sender should keep to be able to respond to the "Resend request"?

[ original email was from John Armstrong - johna@ms.com ]
Implicitly, yes; all of them for the current session(last time you rolled your sequence numbers). If you can’t respond completely to the
request, you should use a SequenceReset.

> Does FIX specify the required number of messages sender should keep to be able to respond to the "Resend request"?
>
>

You will need a message log of messages since your “session” (MsgSeqNum starting at 1) started. Please consider the ramifications of issuing a SeqeunceReset if you can’t respond completely to a ResendRequest. In the event of “missing” some of your outbound messages, issuing a SequenceReset following a ResendRequest could get the session back in sync, however, it could also cause the counterparty to completely miss valuable business messages as a result.

> Implicitly, yes; all of them for the current session(last time you rolled your sequence numbers). If you can’t respond completely to the
> request, you should use a SequenceReset.
>
> > Does FIX specify the required number of messages sender should keep to be able to respond to the “Resend request”?
> >
> >
>