From FIXwiki

FIX Message NetworkCounterpartySystemStatusResponse (MsgType=BD)

MsgType	FIX Specification	First introduced	Deprecated
MsgType=BD	Infrastructure messages - Network	FIX.4.4

This message is sent in response to a Network (Counterparty System) Status Request Message.

If the network response payload is larger than the maximum permitted message size for that FIX conversation the response would be several Network Status Response Messages the first with a status of full and then as many messages, as updates to the first message, adding information as required.

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Notes

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