问题 问答题

【说明】
某企业销售部和售后服务部的网络拓扑结构如图8-5所示。


销售部和售后服务部的员工抱怨由于新服务器的加入而使网络运行速度比以前慢了.系统分析师小郭在调查期间利用手持式诊断工具记录了如下信息。
(1)服务器A(Server

  • A)同时是销售部和服务部的文件和打印服务器,其网络连接运行在78%的平均利用率上。
    (2)销售部的网络平均利用率为45%。
    (3)服务器B(Server
  • B)是一台文件服务器,其上驻留了各种类型的文件,并允许销售部的工作站进行在线文件编辑。它占用销售部所有网络利用率的20%。
    (4)销售部的两个有限授权用户经常以对等工作方式进行网络互联操作。他们占用了销售部所有网络利用率的5%。
    (5)售后服务部的的网络平均利用率为65%。
    (6)服务器C(Server
  • C)中有一套销售部和服务部员工频繁使用的图像库应用软件,它占用销售部,服务部两个部门的所有网络利用率的15%。
    (7)流媒体服务器(Server
  • D)中驻留一套流媒体应用软件,由服务部用于售后服务等培训工作。该应用占用了部门网络利用率的20%。
    系统分析师小郭在调查中了解到该企业工程技术部门已花费了所有资金,已经没有了购买新的网络设备的预算资金。但该工程技术部可在三层交换机(Switchl)上提供6个1 Gb/s交换端口,另外还可提供 3台100Mb/s的交换机、4个1Gb/s网卡和一箱回收的10/100Mb/s网卡。

【问题1】
在图8-5网络拓扑中,服务器A(Server A)的网络利用率性能可以接受吗请简要说明理由。

答案

参考答案:可以接受。因为服务器A连接在三层交换机上,其可接受的利用率为80%

解析:这是一道要求读者掌握交换式网络利用率性能分析的理解题。本题的解答思路如下。
1)网络的性能会受到工作站、服务器接入等外界环境的影响因素。在评估一个网络方案的性能时,必须考虑表8-10中这些因素的影响。
表8-10 影响网络性能的因素表

影响因素
阅读理解

阅读理解。

     Some British and American people like to invite friends for a meal at home. You should not be upset(不安的) if your English friends don't invite you home. It doesn't mean they don't like you. 

     Dinner parties usually start between 7 and 8 pm and end at about 11. Ask your hosts (主人) what

 time you should arrive. It's polite to bring flowers, chocolates or a bottle of wine as a gift. 

     Usually the evening starts with drinks and snacks (小吃). If you want to be extra polite, say how much

  you like the room, or the pictures on the wall. But remember: it's not polite to ask how much things cost. 

     In many families, the husband sits at one of the table and the wife sits at the other end. They eat with

 their guests. 

     You'll probably start the meal with soup or something small, then you'll have meat or fish with

 vegetables, and then dessert (甜点心), followed by coffee. It's polite to finish everything on your plate

 and to take more if you want it.

     Did you enjoy the evening? Call your hosts the next day, or write them a short "thank you" letter. British

  and American people like to say "thank you, thank, thank you" all the time!

1. If your English friend doesn't invite you to dinner at home, it means he or she _____. 

    A. doesn't like you  

    B. likes you    

    C. can't afford to do so  

    D. is too busy

2. It's impolite _____.    

    A. to ask about the price of a certain thing  

    B. to say "thank you" to hosts

    C. take nothing with you when you are invited to dinner  

    D. to eat up everything on your plate

3. The meal ends with _____ usually. 

    A. soup    

    B. coffee      

    C. meat or fish

    D. dessert

4. When you are invited to a dinner party, you'd better _____. 

    A. ask what time you should arrive        

    B. take your wife with you 

    C. drink as more as possible              

    D. eat more snacks as you can

5. Which of the following is true? 

    A. The hosts like the people who sit closer to them. 

    B. The hosts like the people who ask them time, price, age, etc. 

    C. The husband and the wife usually sit together. 

    D. You can call your host the next day or write a letter of thanks after that.