B. 802.3Z C. 802.1Q D. 802.3U
24. A client will use ____ to send emails to mail-server. A. POP3 B. SMTP C. TELNET D. FTP
25. Which protocol used in PPP allows multiple Network layer protocols to be used during a connection? A. LCP B. NCP C. HDLC D. X.25
26. When too many packets are present in the subnet, performance degrades. What is this situation called?
A. dead lock B. congestion C. network fault D. network busy
27. Which language can be used to realize the client-side dynamic web page generation?
A. CGI B. ASP
C. JavaScript D. PHP
28. The two-wire connections between each subscriber’s telephone and the end office are known in the trade as the____.
A. trunk B. local loop C. link D. switch
29. When web page is transmitted over SSL, the protocol used is _____. A. HTTP B. SHTTP C. HTTPS D. SSL
30. Nyquist proved that if an arbitrary signal has been run through a low-pass filter of bandwidth H, the filtered signal can be completely reconstructed by making only ________ (exact) samples per second
A. H B. 0.5H C. 2H D. 4H
31. To convert a binary message to an ASCII message in email system, we can use _____ encoding, which break up groups of 24 bits into four 6-bit units, with each unit being sent as a legal ASCII character.
A. base64 B. quoted-printable C. SMTP D. POP3
32. A CRC generator polynomial is G(x)= X8+X5+X2+l. How many bits will the checksum be? A. 7 B. 8 C. 9 D. 10
33. If the length of sequence is 4 bits, the maximum sending window size should be ____. A. 13 B. 14 C. 15 D. 16
34. In 802.11, to solve the _______ station problem and the hidden station problem, we can use CSMA/CA protocol. According this protocol, before the station sending a data, it must send RTS frame and wait a CTS frame back.
A. fault B. mobile C. exposed D. wireless