Introduction

This document describes Binary Order Entry, version 3 (BOEv3), the CBOE proprietary order entry protocol used by a Trading Privilege Holder (TPH) to send orders and quotes to the Cboe Futures Exchange (CFE) in futures and options products. Features only applicable to Options on Futures will be notated with (Options Only).

Where applicable, the terminology (e.g., time in force) used in this document is similar to that used by the FIX protocol to allow those familiar with FIX to more easily understand BOEv3. This document assumes the reader has basic knowledge of the FIX protocol.

BOEv3 fulfills the following requirements:

• CPU and memory efficiency. Message encoding, decoding, and parsing are simpler to code and can be optimized to use less CPU and memory at runtime.
• Application level simplicity. State transitions are simple and unambiguous. They are easy to apply to a TPH's representation of an order.
• Session level simplicity. The session level protocol (login, sequencing, replay of missed messages, logout) is simple to understand.

While CFE strives to preserve feature parity between FIX and BOEv3 where possible, some features may only be available in one protocol or the other.

Note that while FIX is an ASCII based protocol, BOE is binary based, providing for efficiencies that can allow for reduced latency. Additionally, FIX and BOEv2 messages pass through an additional process not applicable to BOEv3 messages before being ordered for processing by receipt time at the BOEv3 order handler, which can allow for reduced latency for BOEv3 messages relative to FIX/BOEv2 messages.

All binary values are in little-endian (as used by Intel x86 processors), and not network byte order.

Each message is identified by a unique message type. A listing of the supported message types is provided in Session Message Types and Application Message Types.

All communication is via standard TCP/IP.