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exam CCNA(640-047) passing score = 755 no of questions =78 time =120 minutes date 24-11-99 i cleared the ccna(640-047) with 92% marks.it was really a interesting experience for me.the exam was really straight forward.if you have studied the book thoroughly and done practice exams you can get it easily.but one thing to remember you should have some practical experience that can help a lot espacially for configuration questions. i recommend to study todd lamlle book thoroughly .there is some command missing in this book for which u can concern icrc book. some of the areas of question are; 1.osi model questions espacially related to layer functions 2.encapsulation question information is converted into data data into sgments segments into pakets packets into frames frames into bits 3-booting of ios the router boot from three resourses first from flash then from tFtp then from rom the syntax is router(config)#boot system tftp ios filename tftp server address router(config)#boot system flash ios filename router(config)#boot system rom there were 3-4 questions form wan technologies espacially about frame relay and isdn fram relay dlci(use to identify the frame relay virtual circuit) isdn (bri-2b+!d b for data transfer and d for signiling) you should also study tcp dod model thorouhly. espacially functions of lan and wan protocols and on which layer they work i hope you will take advantage hope for best for u in future netguy some helpful q&a for ccna 1) you are reviewing a consultant's design for your 10base2, thin ethernet, network. the following distances are outlined. host a to host b is 190 meters host b to host c is 160 meters host c to host d is 300 meters which distances are too far according to the specification? a. host a to host b b. host b to host c c. host c to host d d. no answer is correct answer: a & c - the specification for 10base2 is 185 meters (600 feet) on coaxial cable. 2) which window size is more efficient? a. window size = 3 b. window size = 1 c. window size = 2 d. window size = 4 e. window size = 5 answer: a - the number of data segments the sender is allowed to have outstanding before it receives and acknowledgment is called the window. a window size of 3 allows the sender to send three data segments before expecting an acknowledgment. a window size of 1 would require an acknowledgment after each data segment. 3) once data transfer is initiated between two hosts, congestion can occur. what are two reasons for congestion? a. a high-speed computer might be able to generate traffic faster than the network can transfer it. b. when datagrams arrive at a host or gateway too quickly to process, they are stored in memory temporarily. the host or gateway can fill its memory so that it can accept no more datagrams. c. different applications can saturate the bandwidth with larger segments than the network can handle. d. some applications are written with less reliability than others are. answer: a & b - a high-speed computer might send traffic faster than the network can transfer it and the host or gateway could exhaust its buffer. the transport layer can issue a "not ready" indicator to the sender so that data is discarded. 4) you are reviewing a consultant's design for your 10base5, thick ethernet, network. the following distances are outlined. host a to host b is 190 meters. host b to host c is 160 meters. host c to host d is 300 meters. host d to host e is 600 meters. which distances are too far according to the specification? a. host a to host b |
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