Sequence number of message block.

Feed identifier.

This field is true if messages has been received within bundle (see BundleMarker).

This field will always be set to `false` for Start of a message bundle. true - When this is the last or only bundle for a transaction. false - When this is not the last or only bundle for a transaction.

Processing latency in microseconds.

Number of messages in message block.

Date-time of the message received.

Date-time of the message sent.

Each message is assigned a sequence number that increases monotonically on the server side. To save bandwidth, the sequence number is a field in the block header, instead of every message. The sequence number for the first message is used in the header, and the client is expected to derive the sequence numbers for subsequent messages in the block. In the case of a heartbeat which includes only header in the block, the expected next sequence number is used.

The session number is used so that a client can easily detect when a new session has started after the daily maintenance window or failure on the server side. It should stay the same for a given multicast channel until a new session has started. It should be noted that the same number can be used by different multicast channels.

Start/End of a message bundle indicator.

The value used to associate bundles of the same transaction. This value will be `0` when the transaction has no trade. The value will be `-1` if the channel does not support sub-bundling.