Most exchanges are structured something like: a.) Each trader has one or more gateway processes that do the order checking/rejecting. b.) Each gateway maintai

Most exchanges are structured something like: a.) Each trader has one or more gateway processes that do the order checking/rejecting. b.) Each gateway maintains a queue of messages for the matching engine. c.) The matching engine/order book for a product pulls one message at a time from each gateway that has a message waiting on its queue and processes it before spinning back to the first gateway again. So a trader blasting the exchange with orders isn't going to impact other traders who also place orders around the same time. She'll only be slowing herself down.