Oracle 11G OCP 1Z0-053 51

（51）To control the execution of a server process when it is receiving bad packets from a potentially malicious client,

you set the SEC_PROTOCOL_ERROR_FURTHER_ACTION initialization parameter as follows:

SQL>ALTER SYSTEM SET SEC_PROTOCOL_ERROR_FURTHER_ACTION = Drop,10;

What is the significance of this setting?

A. It terminates the client connection after 10 bad packets and the client cannot reconnect to the same instance.

B. It terminates the client connection after 10 bad packets but the client can still reconnect,and attempt the same operation again.

C. It terminates the client connection 10 seconds after receiving a bad packet and the client cannot reconnect to the same instance.

D. It terminates the client connection after receiving a bad packet and the client can reconnect to the same instance after 10 minutes.

答案：（B）

解析：

初始化引數：SEC_PROTOCOL_ERROR_FURTHER_ACTION = {CONTINUE | (DELAY, integer) | (DROP, integer)}

CONTINUE--伺服器程式繼續執行, database server可能從屬於Denial of Service(DoS), 如果惡意的客戶端繼續發bad packets

(DELAY, integer)--伺服器端再次接收同一客戶端的下次連線請求時,客戶端要經過integer秒.

                           可以防止惡意的客戶端消耗過多的伺服器端資源,而造成合法的客戶端效能下降

(DROP, integer)--伺服器端在累計達到integer個bad packets後強制終斷客戶端連線.

                         伺服器在客戶端的消耗上保護自己.客戶端可以重新連線產嘗試相同的操作.

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