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| 1 | _______ is a standard developed by ANSI for fiber-optic networks. |
 | A) | SONET |
| B) | SDH |
| C) | either (a) or (b) |
| D) | neither (a) nor (b) |
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| 2 | _______ is a standard developed by ITU-T. |
| A) | SONET |
| B) | SDH |
| C) | either (a) or (b) |
| D) | neither (a) nor (b) |
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| 3 | SONET has defined a hierarchy of signals called ________. |
| A) | STSs |
| B) | STMs |
| C) | either (a) or (b) |
| D) | neither (a) nor (b) |
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| 4 | SDH has defined a hierarchy of signals called ________. |
| A) | STSs |
| B) | STMs |
| C) | either (a) or (b) |
| D) | neither (a) nor (b) |
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| 5 | An ______ signal is the optical modulation of an STS-n (or STM-n) signal. |
| A) | OC-n |
| B) | TDM-n |
| C) | FDM-n |
| D) | none of the above |
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| 6 | .SONET defines _______ layers. |
| A) | two |
| B) | three |
| C) | four |
| D) | five |
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| 7 | SONET is a _______ TDM system. |
| A) | asynchronous |
| B) | synchronous |
| C) | statistical |
| D) | none of the above |
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| 8 | A SONET system can use _________. |
| A) | STS multiplexers |
| B) | regenerators |
| C) | add/drop multiplexers |
| D) | all of the above |
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| 9 | SONET sends ________ frames per second |
| A) | 1000 |
| B) | 2000 |
| C) | 4000 |
| D) | 8000 |
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| 10 | In SONET each frame lasts _______ microseconds. |
| A) | 20 |
| B) | 64 |
| C) | 128 |
| D) | none of the above |
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| 11 | An STS-1 frame is made of ________ rows |
| A) | 1 |
| B) | 9 |
| C) | 90 |
| D) | none of the above |
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| 12 | An STS-1 frame is made ______columns |
| A) | 1 |
| B) | 9 |
| C) | 90 |
| D) | none of the above |
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| 13 | An STS-3 frame is made of ______ rows. |
| A) | 1 |
| B) | 9 |
| C) | 27 |
| D) | none of the above |
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| 14 | An STS-3 frame is made of ________ columns. |
| A) | 9 |
| B) | 90 |
| C) | 270 |
| D) | none of the above |
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| 15 | SONET network topologies can be __________. |
| A) | linear |
| B) | ring |
| C) | mesh |
| D) | all of the above |
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| 16 | A linear SONET network can be __________. |
| A) | point-to-point |
| B) | multipoint |
| C) | either (a) or (b) |
| D) | neither (a) nor (b) |
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| 17 | A ring SONET network can be _________. |
| A) | unidirectional |
| B) | bidirectional. |
| C) | either (a) or (b) |
| D) | neither (a) nor (b) |
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| 18 | To make SONET backward-compatible with the current hierarchy, its frame design includes a system of. |
| A) | OCs |
| B) | STMs |
| C) | STSs |
| D) | VTs |
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| 19 | A ________ is a repeater. |
| A) | regenerator |
| B) | ADM |
| C) | STS multiplexer/demultiplexer |
| D) | none of the above |
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| 20 | __________ allow insertion and extraction of signals. |
| A) | regenerators |
| B) | ADMs |
| C) | STS multiplexer/demultiplexers |
| D) | none of the above |
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| 21 | A _______ is the optical link connecting two neighbor devices. |
| A) | section |
| B) | line |
| C) | path |
| D) | none of the above |
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| 22 | A ______ is the portion of the network between two multiplexers. |
| A) | section |
| B) | line |
| C) | path |
| D) | none of the above |
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| 23 | A ______is the end-to-end portion of the network between two STS multiplexers. |
| A) | section |
| B) | line |
| C) | path |
| D) | none of the above |
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| 24 | The ______ layer is responsible for the movement of a signal from its optical source to its optical destination. |
| A) | section |
| B) | line |
| C) | path |
| D) | photonic |
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| 25 | The ____ layer is responsible for the movement of a signal across a physical line. |
| A) | section |
| B) | line |
| C) | path |
| D) | photonic |
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| 26 | The ______ layer is responsible for the movement of a signal across a physical section. |
| A) | section |
| B) | line |
| C) | path |
| D) | photonic |
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| 27 | The _______ layer corresponds to the physical layer of the OSI model. |
| A) | section |
| B) | line |
| C) | path |
| D) | photonic |
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| 28 | An STS multiplexer is a ______ device. |
| A) | one-layer |
| B) | two-layer |
| C) | three-layer |
| D) | four-layer |
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| 29 | An add/drop multiplexer is a ______ device. |
| A) | one-layer |
| B) | two-layer |
| C) | three-layer |
| D) | four-layer |
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| 30 | A regenerator is a ________ device. |
| A) | one-layer |
| B) | two-layer |
| C) | three-layer |
| D) | four-layer |
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| 31 | In SONET, for each frame, the bytes are transmitted __________. |
| A) | from left to the right, top to bottom |
| B) | from right to the left, bottom to top |
| C) | from left to the right, bottom to top |
| D) | from right to the left, top to bottom |
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| 32 | 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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| 33 | Each ________in a SONET frame can carry a digitized voice channel. |
| A) | bit |
| B) | byte |
| C) | frame |
| D) | none of the above |
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| 34 | The section overhead consists of ______octets. |
| A) | 1 |
| B) | 6 |
| C) | 9 |
| D) | 18 |
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| 35 | Line overhead consists of ________ bytes. |
| A) | 1 |
| B) | 6 |
| C) | 9 |
| D) | 18 |
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| 36 | The path overhead consists of ______ bytes. |
| A) | 1 |
| B) | 6 |
| C) | 9 |
| D) | 18 |
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| 37 | In ________ APS, there are normally two lines: one working line and one protection line. Both lines are active all the time. |
| A) | one-plus-one |
| B) | one-to-one |
| C) | one-to-many |
| D) | none of the above |
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| 38 | In ______ APS, there is one working line and one protection line. The data are normally sent on the working line until it fails. |
| A) | one-plus-one |
| B) | one-to-one |
| C) | one-to-many |
| D) | none of the above |
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| 39 | In ________APS, there is only one protection line for many working lines. When a failure occurs in one of the working lines, the protection line takes control until the failed line is repaired. |
| A) | one-plus-one |
| B) | one-to-one |
| C) | one-to-many |
| D) | none of the above |