CCNA考试练习题.doc

1)What were the two challenges ofcreating anetwork model (Select two) (创建网络模型所遇到的两个挑战是什么(选择 2个))? A,D。互通性和互操作性创建网络模型的挑战。 2)The Advanced Research Projects Agency created work( 高级研究计划局(ARPA)创建了什么网络)? A. C. Ring C。由DARPA项目创建。 3)What does OSI stand for (OSI 代表什么)? anization for Standards Institute anization for Standards Standards Institute Systems Interconnection D。OSI代表开放系统互连。 4)What are the layers ofthe OSI reference model, inorder (OSI 参考模型有哪些层,按顺序回答)? , transport, network, physical , presentation, session, network, transport, data link, physical , presentation, session, transport, network, data link, physical , session, transport, physical 5)What isthe term for wrapping adata unit with aheader and passing ittothe next protocol (用报头包装一个数据信元并传递到下一个协议,代表这个过程的术语是什么)? 6)Which ofthe following isnot defined atthe physical layer ofthe OSI reference model (在 OSI参考模型的物理层中没有定义下面的哪一个)? addresses transmission levels interface 7)Which standards institute created the 802 series ofphysical/data link layer standards (哪个标准协会创建了物理/数据链路层标准的 802系列)? -T 8)Who created (谁创建了)? -T 9)What isthe function ofCSMA/CD (CSMA/CD 的功能是什么)? atoken around astar topology access work and retransmit ifthey detect acollision connect toadual ring offiber-optics and use atoken-passing scheme break the frames into tiny cells and forward them through a cell-work. 10) What isabackoff algorithm? (什么是补偿算法)? fault tolerance calculation for FDDI calculation for determining the best route notification that aserious error has occurred work duration calculation todelay retransmission after a collision, before retransmitting . 11) IBM ’sToken Ring specific