CTS and CQS receive trade and quote information, respectively from NYSE, AMEX, and the other regional market centers using a standard message format.
CTS provides an automated correction processing capability in the event that a market center incorrectly reported its information.
CTS also disseminates at End of Day, closing messages that provide summary information from its database for each listed stock.
For every quote message received from a market center, CQS calculates a National Best Bid and Offer (NBBO) based on a price, size and time priority scheme.
CQS disseminates the Market center's root quote with an appendage that includes the National and NASDAQ BBOs.
Each market center has redundant communication paths into the two operating environments and each uses diverse common telephone carriers to send its trade and quote data to the Securities Industry Automation Corporation (SIAC).
SIAC simultaneously distributes, via IP multicast, trade and quote information to the CTS and CQS subscribers from both sites.