Which two statements are true regarding an Ethernet collision domain?()
AIf a switch is used, the collision domain is limited to each device and the switch.
BIf a hub is used, the collision domain is limited to each device and the hub.
CIf a hub is used, the collision domain includes all devices connected to the hub.
DIf a switch is used, the collision domain includes all devices connected to the switch.
移动通信采用大区制组网具有发射功率高、()设备简单等特点。
A、频率利用率高
B、频率利用率低
C、容量大
D、频率复用
下列运算符中,不能被重载的是( )。
A、&&
B、!=
C、.
D、++
八木天线由一个()、一个反射振子和若干()组成。
简述线程的生命周期,重点注意线程阻塞的几种情况,以及如何重回就绪状态。
In your database, the LDAP_DIRECTORY_SYSAUTH initialization parameter has been set to YES and the users who need to access the database as DBAs have been granted SYSDBA enterprise role in Oracle Internet Directory (OID). SSL and the password file have been configured. A user SCOTT with the SYSDBA privilege tries to connect to the database instance from a remote machine using the command: Which authentication method would be used first?()
A、 authentication by password file
B、 authentication by using certificates over SSL
C、 authentication by using the Oracle Internet Directory
D、 authentication by using the local OS of the database server