Update: OPRA Message Change Prompts Bandwidth Increases

The expanded header message increases OPRA message sizes by 30 percent overall, participants say.


Although consumer firms have been advised by OPRA to ignore the field, vendors who must redistribute the OPRA feed including the new header format say that regardless of whether firms can utilize the expanded data, it still incurs a greater delivery burden.

The old message header format included a participant ID, a message category field, a message type field, and a message indicator field, each accounting for one byte. The header now includes a new, eight-byte transaction ID field, bringing the