OnixS EBS BrokerTec Handler for C++ distinguishes the following types of sessions:

1. MarketData
2. FullMarketData
3. Normal
4. Clearing
5. FirmOrderBook

Each of the above can be combined, e.g. "MarketData | FullMarketData".

Main Session

The first session, that is called as Main, is of great importance. Moreover, if it is the only one, it must be able as receive market data as execute trading operations (if it is necessary). The table below shows the required and optional transactions and broadcasts that the handler can use in dependence on the registered listeners.

Main session can have any of the session types presented above, but the normal work of the Handler suggests that it will be used to obtain market data and or perform transactions. All additional sessions are used for execute trading operations.

Required and optional OMnet messages

In the table below listed OMnet transactions and broadcasts which currently required (red) or optional (blue) for different session types:

	Main	MarketData	FullMarketData	Normal	Clearing	FirmOrderBook
UQ12
UQ14
UQ15
DQ6
DQ7
DQ8
DQ29
DQ152
DQ153
DQ154
DQ160
MQ7
MQ8
MQ9
IQ10
MO4
MO31
MO33
MO40
BD1
BD2
BD6
BO5
BO14
BO23
BI9
BI41
BI67
BI81
BI99
BU37
BU152
BU154
BU160

Note

Required (red) check mark for broadcasts in Main column means that the corresponding broadcast is required only if type of Main session is the same as the type of session for which message is required. Subscription to the broadcast will be performed only for Main session.