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| 1 | |
Communication at the data-link layer is ___________________. |
| | A) | end-to-end |
| | B) | node-to-node |
| | C) | process-to-process |
| | D) | None of the choices are correct |
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| 2 | |
Which of the following best describes a single-bit error? |
| | A) | A single bit is inverted. |
| | B) | A single bit per transmission is inverted. |
| | C) | A single bit per data unit is inverted. |
| | D) | All of the choices are correct |
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| 3 | |
Which error detection method uses one's complement arithmetic? |
| | A) | Simple parity check |
| | B) | Checksum |
| | C) | Two-dimensional parity check |
| | D) | CRC |
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| 4 | |
Which error detection method consists of just one redundant bit per data unit? |
| | A) | Two-dimensional parity check |
| | B) | CRC |
| | C) | Simple parity check |
| | D) | Checksum |
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| 5 | |
Which error detection method involves polynomials? |
| | A) | CRC |
| | B) | Simple parity check |
| | C) | Two-dimensional parity check |
| | D) | Checksum |
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| 6 | |
If the ASCII character G is sent and the character D is received, what type of error is this? |
| | A) | Single-bit |
| | B) | Multiple-bit |
| | C) | Burst |
| | D) | Recoverable |
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| 7 | |
If the ASCII character H is sent and the character L is received, what type of error is this? |
| | A) | Burst |
| | B) | Recoverable |
| | C) | Single-bit |
| | D) | Multiple-bit |
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| 8 | |
In cyclic redundancy checking, what forms the check bits? |
| | A) | The remainder |
| | B) | The divisor |
| | C) | The quotient |
| | D) | The dividend |
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| 9 | |
In CRC, if the dataword is 111111, the divisor 1010, and the remainder 110, what is the codeword at the receiver? |
| | A) | 111111011 |
| | B) | 1010110 |
| | C) | 111111110 |
| | D) | 110111111 |
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| 10 | |
In CRC, if the dataword is 111111 and the divisor 1010, what is the dividend at the sender? |
| | A) | 1111110000 |
| | B) | 111111000 |
| | C) | 111111 |
| | D) | 1111111010 |
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| 11 | |
At the CRC generator, _______ is (are) added to the dataword after the division process to create the codeword. |
| | A) | 0s |
| | B) | 1s |
| | C) | the remainder |
| | D) | the divisor |
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| 12 | |
The sum of the checksum and data at the receiver is _______ if no error is detected. |
| | A) | – 0 |
| | B) | + 0 |
| | C) | the complement of the checksum |
| | D) | the complement of the dataword |
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| 13 | |
In CRC, the quotient at the sender _______. |
| | A) | becomes the dividend at the receiver |
| | B) | becomes the divisor at the receiver |
| | C) | is the remainder |
| | D) | is discarded |
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| 14 | |
At the CRC checker, _______ means that the dataword is damaged. |
| | A) | a string of alternating 1s and 0s |
| | B) | a nonzero remainder |
| | C) | a string of 0s |
| | D) | None of the choices are correct |
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| 15 | |
HDLC is an acronym for _______. |
| | A) | High-Duplex Line Communication |
| | B) | Half-Duplex Link Combination |
| | C) | High-Level Data Link Control |
| | D) | Host Double-Level Circuit |
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| 16 | |
The shortest frame in HDLC protocol is usually the _______ frame. |
| | A) | information |
| | B) | management |
| | C) | supervisory |
| | D) | none of the choices are correct |
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| 17 | |
The address field of a frame in HDLC protocol contains the address of the _______ station. |
| | A) | primary |
| | B) | secondary |
| | C) | tertiary |
| | D) | primary or secondary |
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| 18 | |
The HDLC _______ field defines the beginning and end of a frame. |
| | A) | control |
| | B) | flag |
| | C) | FCS |
| | D) | None of the choices are correct |
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| 19 | |
What is present in all HDLC control fields? |
| | A) | N(R) |
| | B) | N(S) |
| | C) | code bits |
| | D) | P/F bit |
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| 20 | |
According to the PPP transition phases diagram, options are negotiated in the _______ state. |
| | A) | Networking |
| | B) | Terminating |
| | C) | Establishing |
| | D) | Authenticating |
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| 21 | |
According to the PPP transition phases diagram, verification of user identification occurs in the _______ state. |
| | A) | Networking |
| | B) | Terminating |
| | C) | Establishing |
| | D) | Authenticating |
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| 22 | |
In the PPP frame, the _______ field defines the contents of the data field. |
| | A) | FCS |
| | B) | flag |
| | C) | control |
| | D) | protocol |
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| 23 | |
In the PPP frame, the _______ field is similar to that of the U-frame in HDLC. |
| | A) | flag |
| | B) | protocol |
| | C) | FCS |
| | D) | control |
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| 24 | |
In the PPP frame, the _______ field has a value of 11111111 to indicate the broadcast address of HDLC. |
| | A) | protocol |
| | B) | address |
| | C) | control |
| | D) | FCS |
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| 25 | |
In PPP, what is the purpose of LCP packets? |
| | A) | Configuration |
| | B) | Termination |
| | C) | Option negotiation |
| | D) | All of the choices are correct |
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| 26 | |
In the PPP frame, the _______ field is for error control. |
| | A) | FCS |
| | B) | flag |
| | C) | control |
| | D) | protocol |
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| 27 | |
For CHAP authentication, the user takes the system's _______ and its own _______ to create a result that is then sent to the system. |
| | A) | authentication identification; password |
| | B) | password; authentication identification |
| | C) | challenge value; password |
| | D) | password; challenge value |
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| 28 | |
In the _______ random-access method collision is avoided. |
| | A) | CSMA/CD |
| | B) | CSMA/CA |
| | C) | ALOHA |
| | D) | token-passing |
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| 29 | |
In the 1-persistent approach, when a station finds an idle line, it _______. |
| | A) | sends immediately |
| | B) | waits 0.1 s before sending |
| | C) | waits 1 s before sending |
| | D) | waits a time equal to (1 - p) seconds before sending |
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| 30 | |
_______ requires one primary station and one or more secondary stations. |
| | A) | token ring |
| | B) | reservation |
| | C) | polling |
| | D) | CSMA |
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| 31 | |
In the p-persistent approach, when a station finds an idle line, it _______. |
| | A) | sends immediately |
| | B) | waits 1 s before sending |
| | C) | sends with probability 1 - p |
| | D) | sends with probability p |
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| 32 | |
The 1-persistent approach can be considered a special case of the p-persistent approach with p equal to _______. |
| | A) | 1.0 |
| | B) | 2.0 |
| | C) | 0.1 |
| | D) | 0.5 |
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| 33 | |
In the reservation access method, if there are 10 stations on a network, then there are _______ reservation minislots in the reservation frame. |
| | A) | 10 |
| | B) | 11 |
| | C) | 5 |
| | D) | 9 |
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| 34 | |
_______ is a controlled-access protocol. |
| | A) | FDMA |
| | B) | TDMA |
| | C) | CSMA |
| | D) | Reservation |
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| 35 | |
_______ is (are) a channelization protocol. |
| | A) | FDMA |
| | B) | TDMA |
| | C) | CDMA |
| | D) | All the choices are correct. |
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| 36 | |
In the _______ random-access method, stations do not sense the medium. |
| | A) | CSMA/CA |
| | B) | ALOHA |
| | C) | CSMA/CD |
| | D) | Ethernet |
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| 37 | |
A ________ is a local address. Its jurisdiction is over a local network. |
| | A) | link-layer address |
| | B) | logical address |
| | C) | port number |
| | D) | None of the choices are correct |
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| 38 | |
If the sender is a host and wants to send a packet to another host on the same network, the logical address that must be mapped to a physical address is ______. |
| | A) | the destination IP address in the datagram header |
| | B) | the IP address of the router found in the routing table |
| | C) | the source IP address |
| | D) | None of the choices are correct |
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| 39 | |
If the sender is a host and wants to send a packet to another host on another network, the logical address that must be mapped to a physical address is ______. |
| | A) | the destination IP address in the datagram header |
| | B) | the IP address of the router found in the routing table |
| | C) | the source IP address |
| | D) | None of the choices are correct |
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| 40 | |
The sender is a router that has received a datagram destined for a host on another network. The logical address that must be mapped to a physical address is ______. |
| | A) | the destination IP address in the datagram header |
| | B) | the IP address of the router found in the routing table |
| | C) | the source IP address |
| | D) | None of the choices are correct |
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| 41 | |
The sender is a router that has received a datagram destined for a host in the same network. The logical address that must be mapped to a physical address is ______. |
| | A) | the destination IP address in the datagram header |
| | B) | the IP address of the router found in the routing table |
| | C) | source IP address |
| | D) | None of the choices are correct |
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| 42 | |
An ARP reply is normally _______. |
| | A) | broadcast |
| | B) | multicast |
| | C) | unicast |
| | D) | None of the choices are correct |
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| 43 | |
An ARP request is normally _______. |
| | A) | broadcast |
| | B) | multicast |
| | C) | unicast |
| | D) | None of the choices are correct |
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| 44 | |
Given the Ethernet address 01011010 00010001 01010101 00011000 10101010 00001111 in binary, what is the address in hexadecimal notation? |
| | A) | 5A:88:AA:18:55:F0 |
| | B) | 5A:81:BA:81:AA:0F |
| | C) | 5A:18:5A:18:55:0F |
| | D) | 5A:11:55:18:AA:0F |
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| 45 | |
If an Ethernet destination address is 07:01:02:03:04:05, then this is a ______ address. |
| | A) | unicast |
| | B) | multicast |
| | C) | broadcast |
| | D) | either multicast or broadcast |
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| 46 | |
If an Ethernet destination address is 08:07:06:05:44:33, then this is a ______ address. |
| | A) | unicast |
| | B) | multicast |
| | C) | broadcast |
| | D) | either multicast or broadcast |
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| 47 | |
Which of the following could not be an Ethernet multicast destination address? |
| | A) | 43:7B:6C:DE:10:00 |
| | B) | 44:AA:C1:23:45:32 |
| | C) | 46:56:21:1A:DE:F4 |
| | D) | 48:32:21:21:4D:34 |
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| 48 | |
Which of the following could not be an Ethernet unicast destination address? |
| | A) | B7:7B:6C:DE:10:00 |
| | B) | 7B:AA:C1:23:45:32 |
| | C) | 7C:56:21:1A:DE:F4 |
| | D) | 83:32:21:21:4D:34 |
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| 49 | |
The _______ layer of Ethernet consists of the LLC sublayer and the MAC sublayer. |
| | A) | data link |
| | B) | physical |
| | C) | network |
| | D) | None of the choices are correct. |
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| 50 | |
The _____ sublayer is responsible for the operation of the CSMA/CD access method and framing. |
| | A) | LLC |
| | B) | MII |
| | C) | MAC |
| | D) | None of the choices are correct, |
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| 51 | |
Each station on an Ethernet network has a unique _______ address imprinted on its network interface card (NIC). |
| | A) | 16-bit |
| | B) | 32-bit |
| | C) | 64-bit |
| | D) | None of the choices are correct. |
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| 52 | |
The minimum frame length for Ethernet is _______ bytes. |
| | A) | 32 |
| | B) | 80 |
| | C) | 128 |
| | D) | None of the choices are correct |
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| 53 | |
Fast Ethernet has a data rate of ________ Mbps. |
| | A) | 10 |
| | B) | 100 |
| | C) | 1000 |
| | D) | 10,000 |
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| 54 | |
In _________, autonegotiation allows two devices to negotiate the mode or data rate of operation. |
| | A) | Standard |
| | B) | Fast Ethernet |
| | C) | Gigabit Ethernet |
| | D) | Ten-Gigabit Ethernet |
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| 55 | |
Gigabit Ethernet has a data rate of ________ Mbps. |
| | A) | 10 |
| | B) | 100 |
| | C) | 1000 |
| | D) | 10,000 |
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| 56 | |
In Ethernet addressing, if the least significant bit of the first byte is 0, the address is _________. |
| | A) | unicast |
| | B) | multicast |
| | C) | broadcast |
| | D) | None of the choices are correct. |
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| 57 | |
In Ethernet addressing, if the least significant bit of the first byte is 1, the address is _________. |
| | A) | unicast |
| | B) | multicast |
| | C) | broadcast |
| | D) | None of the choices are correct. |
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| 58 | |
In Ethernet addressing, if all the bits are 1s, the address is _________. |
| | A) | unicast |
| | B) | multicast |
| | C) | broadcast |
| | D) | None of the choices are correct. |
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| 59 | |
In the Ethernet, the _______ field is actually added at the physical layer and is not (formally) part of the frame. |
| | A) | CRC |
| | B) | preamble |
| | C) | address |
| | D) | SFD |
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| 60 | |
In the Ethernet frame, the _______ field contains error detection information. |
| | A) | CRC |
| | B) | preamble |
| | C) | address |
| | D) | SFD |
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| 61 | |
A VLAN as a local area network configured by_____________. |
| | A) | software |
| | B) | physical wiring |
| | C) | software or physical wiring |
| | D) | None of the choices are correct. |
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| 62 | |
The largest portion of the bandwidth for ADSL carries _______. |
| | A) | voice communication |
| | B) | upstream data |
| | C) | downstream data |
| | D) | control data |
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| 63 | |
Another name for the cable TV office is the _______. |
| | A) | splitter |
| | B) | fiber node |
| | C) | combiner |
| | D) | head end |
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| 64 | |
A traditional cable TV network transmits signals ______. |
| | A) | upstream |
| | B) | downstream |
| | C) | upstream and downstream |
| | D) | None of the choices are correct. |
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| 65 | |
The original telephone network, which is referred to as the plain old telephone system (POTS), was a (an) ________ system. |
| | A) | digital |
| | B) | analog |
| | C) | digital as well as analog |
| | D) | None of the choices are correct. |
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| 66 | |
The traditional cable TV system used ________ cable end to end. |
| | A) | twisted-pair |
| | B) | coaxial |
| | C) | fiber-optic |
| | D) | None of the choices are correct. |
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| 67 | |
The second generation of cable networks is called a(n) _________ network. |
| | A) | HFC |
| | B) | HCF |
| | C) | CFH |
| | D) | None of the choices are correct. |
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| 68 | |
The HFC network uses _______ cable. |
| | A) | twisted-pair |
| | B) | coaxial |
| | C) | fiber-optic |
| | D) | a combination of coaxial and fiber-optic |
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| 69 | |
To use a cable network for data transmission, we need two key devices: a ______ and a _________ |
| | A) | CM; CMS |
| | B) | CT; CMTS |
| | C) | CM; CMTS |
| | D) | None of the choices are correct. |
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| 70 | |
A (An) ______ signal is the corresponding optical signals of an electrical signal level STS-n. |
| | A) | OC-n |
| | B) | TDM-n |
| | C) | FDM-n |
| | D) | None of the choices are correct. |
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| 71 | |
SONET uses _______ TDM multiplexing. |
| | A) | asynchronous |
| | B) | synchronous |
| | C) | statistical |
| | D) | None of the choices are correct. |
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| 72 | |
A SONET system can use _________. |
| | A) | STS multiplexers |
| | B) | regenerators |
| | C) | add/drop multiplexers |
| | D) | All of the choices are correct. |
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| 73 | |
SONET sends ________ frames per second |
| | A) | 1000 |
| | B) | 2000 |
| | C) | 4000 |
| | D) | 8000 |
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| 74 | |
In SONET, a ________ is a repeater. |
| | A) | regenerator |
| | B) | ADM |
| | C) | STS multiplexer/demultiplexer |
| | D) | None of the choices are correct. |
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| 75 | |
In SONET, __________ allow insertion and extraction of signals. |
| | A) | regenerators |
| | B) | ADMs |
| | C) | STS multiplexer/demultiplexers |
| | D) | none of the choices are correct |
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| 76 | |
In SONET, for each byte, the bits are transmitted ____________. |
| | A) | from least significant to the most significant |
| | B) | from most significant to the least significant |
| | C) | two at a time |
| | D) | three at a time |
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| 77 | |
________ is the cell relay protocol designed by the corresponding Forum and adopted by the ITU-T. |
| | A) | SONET |
| | B) | ADM |
| | C) | ATM |
| | D) | None of the choices are correct. |
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| 78 | |
The ATM standard defines ______ layers. |
| | A) | two |
| | B) | three |
| | C) | four |
| | D) | five |
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| 79 | |
An ATM data unit is a cell composed of ______ bytes. |
| | A) | 40 |
| | B) | 50 |
| | C) | 52 |
| | D) | 53 |
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| 80 | |
In ATM, a(n) ______ is the interface between a user and an ATM switch. |
| | A) | UNI |
| | B) | NNI |
| | C) | NUI |
| | D) | None of the choices are correct. |
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| 81 | |
In ATM, a(n) _________ is the interface between two ATM switches. |
| | A) | UNI |
| | B) | NNI |
| | C) | NUI |
| | D) | None of the choices are correct. |
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| 82 | |
In ATM, the _______ layer accepts transmissions from upper-layer services and maps them into cells. |
| | A) | physical |
| | B) | ATM |
| | C) | AAL |
| | D) | None of the choices are correct. |
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| 83 | |
In ATM, the ______ layer provides routing, traffic management, switching, and multiplexing services. |
| | A) | physical |
| | B) | ATM |
| | C) | AAL |
| | D) | None of the choices are correct. |
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| 84 | |
A repeater is a connecting device that operates in the _______ layer(s). |
| | A) | physical |
| | B) | physical and data link |
| | C) | data link and network |
| | D) | physical, data link and network |
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| 85 | |
A link-layer switch is a connecting device that operates in the _______ layer(s). |
| | A) | physical |
| | B) | physical and data link |
| | C) | data link and network |
| | D) | physical, data link and network |
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| 86 | |
A router is a connecting device that that operates in the _______ layer(s). |
| | A) | physical |
| | B) | physical and data link |
| | C) | data link and network |
| | D) | physical, data link and network |
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| 87 | |
A _________ has no filtering capability. |
| | A) | repeater |
| | B) | link-layer switch |
| | C) | router |
| | D) | None of the choices are correct. |
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| 88 | |
A three-layer switch is a __________. |
| | A) | repeater |
| | B) | link-layer switch |
| | C) | router |
| | D) | None of the choices are correct. |
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