Session-Level Messages
Resend Request <2>
Send a Resend Request to ask the counterparty to retransmit messages. Use this message when you detect a sequence gap, lose a message, or initialize a session.
You can request a single message, a message range, or all messages after a specific sequence number.
Consider message type before resending. If market conditions changed since an order was created, do not retransmit stale orders. Use Sequence Reset <4> (Gap Fill) to skip unneeded messages.
You must process messages in sequential order. If you miss message 7 and receive messages 8–9, ignore 8 and 9 and request a resend starting at 7 (BeginSeqNo=7, EndSeqNo=0). Setting EndSeqNo=0 (infinity) resolves sequence gaps faster during simultaneous recoveries.
- To request a single message: BeginSeqNo
<7>= EndSeqNo<16> - To request a range of messages: BeginSeqNo
<7>= first message of range, EndSeqNo<16>= last message of range - To request all messages after a specific sequence number: BeginSeqNo
<7>= starting sequence number, EndSeqNo<16>=0(represents infinity).
FIELDS
| Tag | Name | Req | Description |
|---|---|---|---|
| Standard Header | Y | MsgType = 2 | |
| 7 | BeginSeqNo | Y | |
| 16 | EndSeqNo | Y | |
| Standard Trailer | Y |