Differences with prior versions of BOE
Notable differences between BOEv3 and the prior major version of BOE (BOEv2) include:
- BOEv3 has statically sized messages except when sizing variability is required due to (statically sized) repeating groups of fields. Consequently, BOEv3 does not support optional fields on input nor bitfield-specified optional return fields. This provides a more consistent and predictable experience for all users.
- The Logout Response message no longer returns the LastReceivedSequenceNumber, nor the highest available sequence numbers of the matching unit(s).
- BOEv3 requires the ClearingFirm be specified on all Cancel Order and Modify Order messages (either via Port default or by specifying in the message). This differs from prior versions of BOE where this was only required of service bureau members.
- When logging in, members may specify a behavior of "Fail" for unspecified matching units (fail the login if a matching unit was not specified). For more information about Fail, Skip, and Replay behaviors, see For more information about Fail, Skip, and Replay behaviors.
- There no longer exists a condition where a member would send a Modify Order followed immediately by a Cancel Order message and it was not deterministic as to which OrigClOrdId value was correct on the Cancel Order message. In BOEv3, the OrigClOrdId on a cancel should be the ClOrdId sent on the most recent Modify Order (or New Order if no modifies have been sent), even if the corresponding response has not yet been seen. CancelOrigOnReject should be set to Y to ensure that a rejected Modify Order does not leave behind a live order.
- Member risk trips and self-imposed lockouts are now required to be reset using the Reset Risk message. They can no longer be reset via the New Order message.
- An InFlight field has been added to most return messages, informing the member of the total number of messages received by the BOEv3 order handler which have not yet been acknowledged by the matching engine.
- BOEv3 Trade Cancel or Correct messages are not suppressible by port parameter.
- In many of the messages from Cboe to Member, the fixed set of fields in the response will be fewer than the total number of fixed and optional fields available via BOEv2.
- For sequenced messages from the member to Cboe, a sequence number of 0 will always be accepted and is treated as if it were the next expected sequence number.
- Symbol Order Rate threshold is no longer an available risk port attribute for BOEv3.
Sustained Order Rate thresholds are no longer available, and instead the use of rate limiting via pause is recommended.
LocateReqd on NewOrderShortUSEquitiesV1 is implied to be a value of 'N', and thus is not a field on the message itself.
Binary Price and Short Binary Price data types have been expanded to have six implied decimals rather than four.
For the Symbol field, only Cboe symbology is now supported, thus the BOEv2 field SymbolSfx is no longer utilized.
BOEv3 will echo reject messages to ODROP.
BOEv3 will exclusively use Order Restated message for any MTP activity, including all MTP cancels. In BOEv2 MTP decrements or cancels was provided to customers via a mix of Order Restated and Order Cancelled messages.