CCNA一OSI参考模型TCPIP协议栈.ppt

每一层对应的PDU TCP/IP参考模型的层次结构 TCP/IP报文封装 TCP/IP报文格式 IP头部（报头）格式 TCP数据段格式 TCP头部结构 UDP数据段格式 UDP数据段格式 常见协议和对应的端口号 例题：1，Segmention of a data stream happens at which layer of the OSI model? A.Physical B.Data Link C.Network D.Transport 2, Router operate at layer____.LAN switches operate at layer____.Ethernet hubs operate at layer____.Word processing operate at layer_____. A. 3,3,1,7 B. 3,2,1,none C. 3,2,1,7 D. 2,3,1,7 E. 3,3,2,none 3, When data is encapsulated,which is correct order ? A. Data,frame,packet,segment,bit B. Segment,data,packet,frame,bit C. Data,segment,packet,frame,bit D. Data,segment,frame,packet,bit Whick type of cable is used to connect the COM port of a host to the COM port of a router switch? A. Crossover B. Straight-through C. Rolled D. Shielded twisted-pair Whick layer of the OSI refernce model users flow control,sequencing,and acknowledgements to ensure that reliable networking occurs? A. Data link B. Network C. Transport D. Presentation E. Physical What is the first 24 bits in a MAC address called？ A. NIC B. BIA C. OUI D. VAI 答案1,D,2,B,3,C When a host transmits data across a network to another host,which process does the data go through A. standardization B. Conversion C. encapsulation D. Synchronization 8. Refer to the exhibit.What type of connection would be supported by the cable diagram show? Pin Number Color Function Pin color Function 1 White/Green TX+ 1 White/Green TX+ 2 Green TX- 2 Green TX- 3 White/Orange RX+ 3 White/Orange RX+ 6 Orange RX- 6 Orange RX- PC to router PC to switch server to router Router to router 答案：4，C,5,C,6,