1. The function of a __________ protocol is to control access
1. The function of...
1. The function of a __________ protocol is to control access to the transmission medium and to provide an orderly and efficient use of that capacity.Submitted: 2 years ago.Category: Homework
A. LLC B. SAN
C. MAC D. MAN
2. Which of the following LAN technologies has the highest capacity?
A. Ethernet B. Fast Ethernet
C. Fiber Channel D. Gigabit Ethernet
3. In general, performance on a LAN _________ with an increase in the number of devices or the length of the wire.
A. increases B. decreases
C. fluctuates D. does not change
4. This long-wavelength option supports duplex links of up to 550 m of 62.5-μm or 50-μm multimode fiber or up to 5 km of 10-μm single mode fiber. Wavelengths are in the range of 1270–1355 nm.
A. 1000BASE-SX B. 1000BASE-T
C. 1000BASE-LX D. 1000BASE-CX
5. Which of the following is the most commonly used standard for computer communications?
A. SLA B. TCP/IP
C. ISO D. USD
6. __________ allows users in two or more locations to interact simultaneously via two-way video and audio transmission.
A. Web conferencing B. Unified messaging
C. Videoconferencing D. Audio conferencing
7. Cables and associated connecting hardware whose transmission characteristics are specified up to _________fall into Category 5 UTP cabling.
A. 50 MHz B. 100 MHz
C. 150 MHz D. 200 MHz
8. A design factor relating to the transmission medium and the signal to determine the data rate and distance is:
A. bandwidth B. transmission impairments
C. interference D. all of the above
9. A basic service set (BSS) is:
A. the smallest building block of a wireless LAN
B. the same as an access point
C. the same as a control module
D. always connected to a backbone distribution system
10. IEEE 802.11 defines a number of services that need to be provided by wireless LAN to provide functionality. Which of the following is not one of these services?
A. Association B. Reassociation
C. Authentication D. Coordination
11. A typical coverage area for a WLAN has a diameter of _________.
A. 25 – 50 m B. 100 – 300 m
C. 150 – 250 m D. 200 – 300 m
12. IEEE 802.11 defines _______ services that need to be provided by the WLAN to achieve functionality equivalent to that which is inherent to wired LANs.
A. ten B. nine
C. eight D. seven
13. A station of this type either is stationary or moves only within the direct communication range of the communicating stations of a single BSS.
A. ISS transition B. no transition
C. BSS transition D. ESS transition
14. The physical layer for IEEE 802.11 has been issued in _______ stages.
A. 3 B. 5
C. 7 D. 9
15. Any entity that has station functionality and provides access to the distribution system via the wireless medium for associated stations.
A. access point B. basic service set
C. extended service set D. coordination function
16. Information that is delivered as a unit between MAC users.
A. MPDU B. ESS
C. MSDU D. DS
17. Each signal change or element is called a:
A. bit B. byte
C. baud D. signal
18. If a carrier wave is modulated with 4 amplitudes and 4 phase changes, how many possible signal combinations are there?
A. 4 B. 8
C. 16 D. 32
19. In Non Return to Zero encoding schemes, the signal or voltage level does not return to 0v (zero volts); one of the problems with this type of encoding is that:
A. it is sometimes difficult to synchronize the timing of the transmitter and the receiver
B. it does not work well with serial communications
C. the signal ground of the transmitter is often different from that of the receiver
D. it works only for analog signals
20. Asynchronous transmission includes a start and stop bit with each character transmitted to ensure:
A. that the total number of bits is a factor of 10
B. to allow a continuous stream of data
C. to prevent single bit errors from occurring
D. to allow the receiver to maintain synchronization with the sender
21. The efficiency of an asynchronous transmission using 1 stop bit, 1 start bit, and 1 parity bit is:
A. 20% B. 30%
C. 50% D. 70%
22. Standards are important when devices must communicate together; the four characteristics governed by these standards are:
A. mechanical, electrical, functional, and procedural
B. electrical, physical, functional, and signaling
C. fundamental, mechanical, procedural, and protocol
D. protocol, fundamental, physical, and signaling
23. An error-detecting scheme that employs a unique prime number is *****:
A. parity checking B. frame sequence checking
C. error checking and error correcting D. cyclic redundancy check
24. In _________ the phase of the carrier signal is shifted to encode data.
A. PSK B. FSK
C. ASK D. BFSK
25. ________ is concerned with the content of the signal.
A. Digital transmission B. Analog transmission
C. Digital signaling D. Analog signaling
26. Data communications via circuit switching involves three phases
A. connect, transfer, hang-up
B. ring, talk, hang-up
C. dial, transfer, disconnect
D. establishment, data transfer, disconnect
27. Which of the following is NOT one of classes of function for control signaling?
A. establishment B. supervisory
C. call information D. network management
28. Which of the following is NOT one of the stated advantages of packet switching over circuit switching?
A. there is less network delay B. data rate conversion can be provided
C. priorities can be used D. connections are never rejected
29. Which of the following is NOT a reason for network jitter when using packet switching networks?
A. packets may vary in length
B. packets may take different paths through the network
C. packets may encounter network congestion
D. data rates will vary from one trunk line to the next
30. In a __________ network, data entering the network from a station are routed to the destination by being switched from node to node.
A. packet switching B. simple switching
C. switched communication D. all of the above
31. ________ are the branches between exchanges.
A. Subscribers B. Subscriber line
C. Exchanges D. Trunks
32. The heart of the call placement process for VoIP is the ___________, defined in RFC 3261, which is an application-level control protocol for setting up, modifying, and terminating real-time sessions between participants over an IP data network.
A. SIP B. SDP
C. PDP D. POP
33. Which of the following is an advantage of circuit switching?
A. provides speed conversion B. compatible with voice
C. appears nonblocking D. logical multiplexing
34. Prior to cellular radio, mobile radio and telephone services required:
A. a high-power transmitter/receiver
B. multiple transmitters/receivers
C. only one or two dedicated channels
D. that many channels be used, which exceed the frequency capacity
35. When a mobile unit moves, it may connect with a different base station. This action is called ____________.
A. a handoff B. a transfer
C. a reconfiguration D. a dropped signal
36. Which of the following is NOT one of the ways that frequency spectrum can be divided among active users?
A. frequency division multiple access B. time division multiple access
C. code division multiple access D. cell division multiple access
37. Because of the limited frequencies available, a key design element of any cellular system is to ___________.
A. use small cells
B. employ multiple access
C. limit the number of users at one time
D. use as many frequencies as possible
38. Which of the following is NOT one of the components of the WAP specification?
A. A framework for wireless telephony applications
B. A full-featured communications protocol stack
C. A programming model based on the WWW
D. A markup language adhering to XML
39. The WAP Programming Model uses a ________ that acts as a proxy server for the wireless domain.
A. translator B. WAP server
C. gateway D. decoder
40. Peak download rate for a 4G network is __________.
A. 1 Gbps B. 100 Mbps
C. 500 Mbps D. 384 kbps
41. _________ was developed to address the limitations of cellular and other wireless networks for providing data services to mobile devices.
A. WAP B. Droid
C. GEOS D. WML
42. Wireless communications is likely to be viewed as an essential part of enterprise network infrastructure except when:
A. Mobile communication is needed
B. Communication must take place in a hostile or difficult terrain that makes wired communication difficult or impossible
C. Communication facilities must be installed at low initial cost
D. The same information must be broadcast to many locations
43. The first two important applications developed for the ARPANET were:
A. Telnet and FTP B. Telnet and email
C. FTP and email D. email and world-wide-web
44. The problem of using IP numbers for addressing hosts in the Internet are resolved using __________.
A. the concept of domains and the use of domain names
B. the use of Telnet applications
C. the use of email servers
D. splitting IP addresses into four octets
45. A ________ is a site that has a collection of telecommunications equipment and usually refers to ISP or telephone company sites.
A. POP B. NSP
C. CPE D. IXP
46. _________ are programs that extract information from name servers in response to client requests.
A. Name servers B. DNS
C. Resolvers D. IP datagram
47. The domain ________ is for network support centers, Internet service providers, and other network-related organizations.
A. org B. info
C. com D. net
48. The newer IPv6 specification uses addresses to identify hosts that consist of:
A. 128 bits B. 64 bits
C. 32 bits D. 16 bits
49. The _________ is used to send files from one system to another under user command.
A. UDP B. SMTP
C. FTP D. SSH
50. Which of the following does distributed processing typically not support?
A. applications B. device controllers
C. data D. mainframes
51. Which of the following is not a function provided by servers in client/server systems?
A. printing services B. data entry
C. database services D. gateways
52. No redundancy guarantees for servers, storage systems, network equipment, and communication connections to Internet or other networks; single path for power and cooling distribution; no redundant components; and availability: 99.671% are _________ characteristics of data centers.
A. Tier 1 B. Tier 2
C. Tier 3 D. Tier 4
53. With __________ virtualization software is used to allow a piece of computer hardware to simultaneously run multiple operating system images.
A. network B. server
C. operating system D. storage
54. ________ is a method for addressing, creating, updating, or querying relational databases.
A. SQL B. API
C. UTI D. GUI
55. Advantages of a web/database system as compared to a more traditional database approach include:
A. improved functionality and ease of administration
B. ease of administration and transaction tracking
C. rapid development and flexible information presentation
D. easy deployment and improved functionality
56. Email functions concerned with the protocol operations needed to transmit and deliver messages are considered:
A. message transfer agent functions B. client functions
C. email client functions D. user agent functions
57. Which of the following is a true statement regarding SMTP processing of messages?
A. messages typically are sent through multiple SMTP systems while going from the sender to the recipient
B. the SMTP sender remains responsible for a message until it has been delivered to the recipient
C. SMTP does not guarantee that all messages are delivered
D. SMTP attempts to send messages until the recipients become available
58. Which of the following is NOT a standard MIME content type?
A. audio B. binary
C. messages D. image
59. The _________ is fundamentally a client/server application running over the Internet and TCP/IP intranets.
A. World Wide Web B. ADMD
C. MDA D. Hypertext Transfer Protocol
60. The ________ relays mail for one application-level hop.
A. MSA B. MS
C. MTA D. MDA
2. In the Ethernet MAC frame, the data segment has a minimum length of 46 byte Why do we have to have a minimum size of data in this frame?
3. Everyone probably has a wireless router at home and/or at work. Do you think a wireless router is a pure layer 3 device? Why?
4. If a carrier signal uses a combination of modulation methods, how many bits of data can one signal carry with BFSK, QPSK, and 8 possible different amplitude?
5. A packet with the size of 2K bytes goes through a WAN. If the packet goes through 10 store-and-forward switching/routing devices, all of which have the transmitting rate of 2Mbit/s, what is the total delay the packet experiences in this WAN? Please ignore the processing delay and propagation delay.
6. In a highly populated area such as big cities, a cell of a cellular network may have way more user than a cell in other areas. What methods are available for crowded areas?7. In a CDMA network, two users with codes 110110 (user A) and 100101 (user B). What would be the bit sequence for each user in the encoded message “1010”?
8. In a network system the administrator wants to monitor the traffic going through each switch point, and control the routing accordingly to balance traffic going through each link. Please create one distributed solution, one centralized solution, and briefly describe under what conditions one of the two solutions are preferable.