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1 | |
HDLC is an acronym for _______. |
|
| | A) | High-duplex line communication |
| | B) | Half-duplex digital link combination |
| | C) | High-level data link control |
| | D) | Host double-level circuit |
|
2 | |
Flow control is needed to prevent ________. |
|
| | A) | Overflow of the sender buffer |
| | B) | Overflow of the receiver buffer |
| | C) | Bit errors |
| | D) | Collision between sender and receiver |
|
3 | |
In a Go-Back-N ARQ, if the window size is 63, what is the range of sequence numbers? |
|
| | A) | 1 to 63 |
| | B) | 1 to 64 |
| | C) | 0 to 63 |
| | D) | 0 to 64 |
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4 | |
For a sliding window of size n - 1 (n sequence numbers), there can be a maximum of _______ frames sent but unacknowledged. |
|
| | A) | 0 |
| | B) | n |
| | C) | n - 1 |
| | D) | n + 1 |
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5 | |
When data and acknowledgment are sent on the same frame, this is called _______. |
|
| | A) | Backpacking |
| | B) | Piggypacking |
| | C) | Piggybacking |
| | D) | A good idea |
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6 | |
In _______ ARQ, if a NAK is received, only the specific damaged or lost frame is retransmitted. |
|
| | A) | Go-Back-N |
| | B) | Stop-and-Wait |
| | C) | Selective Repeat |
| | D) | (a) and (b) |
|
7 | |
ARQ stands for _______. |
|
| | A) | Automatic repeat request |
| | B) | Automatic retransmission request |
| | C) | Acknowledge repeat request |
| | D) | Automatic repeat quantization |
|
8 | |
In Go-Back-N ARQ, if frames 4, 5, and 6 are received successfully, the receiver may send an ACK _______ to the sender. |
|
| | A) | 5 |
| | B) | 6 |
| | C) | 7 |
| | D) | Any of the above |
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9 | |
The shortest frame in HDLC protocol is usually the _______ frame. |
|
| | A) | Information |
| | B) | Management |
| | C) | Supervisory |
| | D) | None of the above |
|
10 | |
The address field of a frame in HDLC protocol contains the address of the _______ station. |
|
| | A) | Primary |
| | B) | Secondary |
| | C) | Tertiary |
| | D) | (a) or (b) |
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11 | |
The HDLC _______ field defines the beginning and end of a frame. |
|
| | A) | Address |
| | B) | Control |
| | C) | Flag |
| | D) | FCS |
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12 | |
A timer is set when _______ is (are) sent out. |
|
| | A) | An ACK |
| | B) | A NAK |
| | C) | A data frame |
| | D) | All the above |
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13 | |
For Stop-and-Wait ARQ, for n data packets sent, _______ acknowledgments are needed. |
|
| | A) | n - 1 |
| | B) | n + 1 |
| | C) | n |
| | D) | 2n |
|
14 | |
What is present in all HDLC control fields? |
|
| | A) | N(R) |
| | B) | N(S) |
| | C) | Code bits |
| | D) | P/F bit |