You are an experienced network administrator in an international corporation. One of your clients asks you to configure a network for a financial trading center which requires multiple high-value transactions. And the transactions are very important to the client. In such a situation, which two of the following are basic and most important requirements concerning the configuration? （）(Choose two.)

A. no single point of failure
B. determine which protocol to use
C. trading database server location
D. deterministic response to all failure