8. Examine the ICMP error packet in your screenshot. It has more fields than the ICMP echo packet. What is included in those fields?
其中的IP字段 ICMP错误数据报 其中的ICMP字段
答：ICMP错误数据报包括;所有IP字段和原来的ICMP字段。
9. Examine the last three ICMP packets received by the source host. How are these packets different from the ICMP error packets? Why are they different?
类型码和编码都为0
答：最后三个ICMP数据报类型码都为0，是回显回答，而不是11（TTL过期），它不同于错误报文段是引文数据报在TTL过期之前已经全部送往目的地。
10. Within the tracert measurements, is there a link whose delay is signific
antlylonger than others? Refer to the screenshot in Figure 4, is there a link whose delay is significantly longer than others? On the basis of the router names, can you guess the location of the two routers on the end of this link?
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该服务器位于荷兰（nl）。
答：从上面截图可以看到，在第12和13步间的延时比较大，这个链接是位于中国和荷兰的路由器上。
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