下图是主机A发送的数据包通过路由器转发到主机B的过程示意图。
根据图中给出的信息，数据包2的目的IP地址和目的MAC地址分别是（）
A．222.4.59.2和00d0.63c3.3c41
B．222.4.59.1和00c0.4c3a.285f
C．222.4.57.2和00d0.63c3.3c41
D．222.4.59.2和00c0.4c3a.285f
参考答案：A
解析：
在数据分组通过路由器转发时，它的目的地址是不变的，始终是目的主机的IP地址；但数据包的目的MAC地址是不断变化的。在本题中，数据包2的目的IP地址始终是主机B的IP地址，即222.4.59.2；另外，数据包2是传送给路由器R2的，所以其目的MAC地址为R2的MAC地址00d0.63c3.3c41。
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| This is a story about a man and his son who went out to 1 a walk. The man had on a pair of odd (不配对的) shoes. 2 he came out in the street, he felt uncomfortable (不舒服). Turning to his son, he said, "Why is one of my legs 3 than 4 today?" The son 5 his father's legs and said, "You put on odd shoes." When he 6 this, the man was 7 and said, "What a clever son!" Then he 8 his son to go back to the house and get 9 pair of shoes for him. When the son went back, he said to his father, "I really 10 two shoes, but one has a thick sole (鞋底) and the other has a thin one." | ||||
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