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18 Cards in this Set
- Front
- Back
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What type of signaling is -48V DC when idle, and then a loop is closed and current flows when off-hook happens? |
Loop start |
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What problem occurs in loop start signaling when the CO switch and FXO port seize the trunk at the same time? |
Glare |
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How do you correct glare? |
Use ground-start signaling |
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How many Kbps is an ISDN B-channel? (Bearer) |
32 Kbps |
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How many Kbps is an ISDN D channel? (Signaling) |
16 Kbps |
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What is a BRI made up of? |
2B + D |
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What is a PRI made up of? |
23B + D for a T1, or 30B + D for an E1 |
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What is the bit-rate for a T1? |
1.544Mbps |
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What protocol is used for feature transparency between different vendor PBXs? |
QSIG |
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What type of signaling does not reserve a separate channel for signaling, but is in-band? |
CAS - Channel Associated Signaling |
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What is the equivalent of T1 CAS for E1 systems? |
E1 R2
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What protocol allows a single D channel to control multiple PRI interfaces? |
NFAS - Non-facility Associated Signaling |
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Caller ID does not work on FXO supports when used with the ________ protocol |
MGCP |
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In fax ________ mode, voice gateways do not distinguish a fax call from a voice call. |
Pass-through |
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Fax Pass-through requires that ______ is disabled |
VAD (voice-activity detection) |
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Fax __________ demodulates the T.30 fax at the originating gateway and sends the information across the IP network enveloped into packets. |
Relay |
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What is the standards-based fax-relay protocol? |
T.38 |
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What fax format converts a fax to a TIFF image and then emails it? |
store-and-forward |
