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 failures