Symbol Ranges, Units, and Sequence Numbers

Symbols will be separated into units and symbol distribution (see Limitations/Configurations) will not change intraday. However, Cboe reserves the right to add multicast addresses or change the symbol distribution with 48 hours prior notice to users. Care should be taken to ensure that address changes, address additions, and symbol distribution changes can be supported easily.

Message sequence numbers are incremented by one for every sequenced message within a particular symbol unit. It is important to understand that one or more units will be delivered on a single multicast address. As with symbol ranges, unit distribution across multicast addresses will not change intraday but may change after notice has been given.

Symbol distribution across units as well as unit distribution across multicast addresses are identical for real-time and gap response multicast addresses.