问题 单项选择题

某城域网拓扑结构如下图所示。如果该路由器R1接收到一个源IP地址为192.168.1.10、目的IP地址为192.168.3.20的IP数据报,那么它将把此IP数据报投递到U地址为()的路由器端口上。

 

A.192.168.66.1

B.192.168.66.2

C. 192.168.67.1

D.192.168.67.2

答案

参考答案:C

解析:

在图中所示的城域网拓扑结构中,路由器R1接收到一个源IP为192.168.1.10。目的IP地址为192.168.3.20的IP数据报。其中,192.168.1.10属于192.168.1.0/24网段的IP地址,即该IP数据报来源于路由器R1的E0端口;192.168.3.20属于192.168.3./24网段的IP地址,因此路由器R1将把此IP数据报投递到D地址为192.168.67.1的路由器端口上,即该IP数据报将从路由器R1的S1端口投递给下一个邻居路由器。该邻居路由器将从IP地址为192.168.67.1的S1端口接收到此数据报。可见IP地址192.168.67.1是源IP地址为192.168.1.10。目的U地址为192.168.1.20的IP数据报的下一跳路由地址。

多项选择题
单项选择题

The first and most important agents of socialization are the people who care for infants. In the earliest months, messages from nurturers constitute the child’’s basic understanding of the world around it. This is the infant’’s first introduction to the language that shapes perception and elicits emotion.Another powerful source of information and socialization is the friendship of peers. Peers are equals that one can deal with on the same level as oneself, whereas parents are superiors. The heavy emotional overlay of family relationships makes some kinds of learning difficult.Much formal socialization is placed in the hands of professionals. Teachers from kindergarten on are specifically designated agents of socialization. Ideally, a teacher is one who has both knowledge and the skills to present it. During the course of teaching their subjects, classroom instructors provide role models and attempt to convey the excitement of learning itself.In earlier times, parents, friends and teachers would comprise the list of primary childhood socializers. Children’’s books, comics and magazines might also have been mentioned as sources of information on norms and role models. Today one must add three powerful indirect or non-personal socialization agents: radio, movies and television. Many people learn about politics, form a vision of well-being, and develop attitudes towards others from what they see on the screen and hear through the speakers.

________are/is powerful indirect socialization agents.

A.Parents

B.Friends

C.Teachers

D.The media