SUBJECTS
|
BROWSE
|
CAREER CENTER
|
POPULAR
|
JOIN
|
LOGIN
Business Skills
|
Soft Skills
|
Basic Literacy
|
Certifications
About
|
Help
|
Privacy
|
Terms
|
Email
Search
Test your basic knowledge |
CCNA Voice - 3
Start Test
Study First
Subjects
:
cisco
,
it-skills
,
ccna
Instructions:
Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can
study here
.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.
This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.
1. How many times can a digital to analog conversion in my network and PSTN total network happen - __ speech is less robust conversion
adaptive differential pulse code modulation (ADPCM) - G.726 - 32
7 - compressed
groups payload - qos - combining
sizing
2. ___ ___ are used within Cisco IOS Software to determine what level of ___ - if any - exists within the network.
RTP timestamps - jitter
continuous media - timing reconstruction
ends - begin - background noise - signal-to-noise threshold
250 - 250 - 500
3. __ __ replays the last packet received
Handling delay - queuing delay
jitter
concealment strategy
jitter buffer
4. A __ can trick the human ear into perceiving a higher-quality voice - but a __ cannot be tricked.
software - dynamic - RTP
Reliable User Data Protocol (RUDP) - UDP - TCP - RUDP
250 - 250 - 500
person - computer
5. Caused by the length a signal must travel via light in fiber or electrical impulse in copper-based networks.
concealment strategy
G.726 - ADPCM - 40 - 32 - 24 - 16
adaptive differential pulse code modulation (ADPCM) - G.726 - 32
Propagation delay
6. __ is not wasting __ when there is no sound to transmit. At least __ % is wasted
jitter
VAD - bandwidth - 50
sizing
busy house
7. __ builds in some reliability to the connectionless __ protocol - enables reliability with out using the overhead of __ - what protocol send multiples of the same packet __
jitter buffer
Reliable User Data Protocol (RUDP) - UDP - TCP - RUDP
forward error correction (FEC)
VAD - bandwidth - 50
8. The jitter buffer found within Cisco IOS ___ is considered a __ queue. This queue can grow or shrink exponentially depending on the interarrival time of the __ packets.
purchase leased lines - purchase VPN and use access code - OR put voice on data network
QoS
software - dynamic - RTP
echo cancelers - software - DSP
9. Echo cancellers are limited by the total amount of time they wait for the reflected speech to be received __ __. A good time to configure is __ms
RTP timestamps - jitter
amplitude - hangover
echo tail - 25
IP - RTP - UDP
10. __ describes __ coding at __ - __ - __ and __ Kbps; you also can interchange ADPCM voice between packet voice and public phone or PBX networks
7 - compressed
IP - RTP - UDP
G.726 - ADPCM - 40 - 32 - 24 - 16
waveform codecs
11. What are 3 things you can do if they want to implement a corporate dial plan
adaptive differential pulse code modulation (ADPCM) - G.726 - 32
purchase leased lines - purchase VPN and use access code - OR put voice on data network
G.728
RTP timestamps - jitter
12. __ recommends no more than __ms delay one-way transmission
G.726 - ADPCM - 40 - 32 - 24 - 16
echo tail - 25
ITU-T - 150
2 - G.723.1
13. The data part of RTP is a thin protocol that provides support for applications with real-time properties - such as __ __ (for example - audio and video) - including __ __ - loss detection - and content identification.
continuous media - timing reconstruction
echo cancelers - software - DSP
concealment strategy
G.711 PCM
14. Defines many different causes of delay (actual packetization - compression - and packet switching) and is caused by devices that forward the frame through the network. Includes __ ___ for congested networks.
VAD - bandwidth - 50
Handling delay - queuing delay
PCM - speech - header - information
waveform codecs
15. When companies merge make sure you configure the __ __
dial plan
jitter
ends - begin - background noise - signal-to-noise threshold
Serialization delay
16. Customers that have almost unlimited bandwidth - however - consider __ a worthwhile mechanism to enhance reliability and voice quality - mechanism makes it more probable that one of the packets will make the journey from sender to receiver
sequence information - time-stamping
IP
forward error correction (FEC)
groups payload - qos - combining
17. Time of day of highest calls on circuit focus those on the __
IP - RTP - UDP
tandom encoding
busy house
Propagation delay
18. These techniques can be grouped together generally as __ __ and include variations such as linear predictive coding (LPC) - code excited linear prediction compression (CELP) - and multipulse - multilevel quantization (MP-MLQ).
sequence number and timestamp
source codecs
busy house
queuing - unacceptable
19. How does G.729 header go __/__/__
IP - RTP - UDP
G.728
RTP is Realtime Transport Protocol - delay sensitive
jitter buffer
20. RTP uses the __ __ to determine whether the packets are arriving in order - and it uses the __ __ information to determine the interarrival packet time (jitter).
waveform codecs
sequence information - time-stamping
begins - front-end speech clipping.
purchase leased lines - purchase VPN and use access code - OR put voice on data network
21. VAD detects a drop-off of speech ___ - it waits a fixed amount of time before it stops putting speech frames in packets. This fixed amount of time is known as __ ( when the person stops talking)
Reliable User Data Protocol (RUDP) - UDP - TCP - RUDP
amplitude - hangover
G.723.1 speech or audio - 6.3 - 5.3
last packet - voice
22. VAD problems in determining when speech __ and __ - and in distinguishing speech from __ __. Its also known as __ __ __ __
IP/RTP/UDP - delay - quality - constrained
begins - front-end speech clipping.
last packet - voice
ends - begin - background noise - signal-to-noise threshold
23. __is characterized as the amount of time it takes for speech to exit the speaker's mouth and reach the listener's ear.
IP
software - dynamic - RTP
Latency
speech degradation
24. On a voip link What is the max packet loss
groups payload - qos - combining
IP/RTP/UDP - delay - quality - constrained
<1%
amplitude - hangover
25. To make audio and video work with RTP what do you need. 2 things
PCM - speech - header - information
echo tail - 25
sequence number and timestamp
Propagation delay
26. __ __ conceals interarrival packet delay variation.
G.729 - voice - 8
jitter buffer
Serialization delay
250 - 250 - 500
27. RTP consists of a __ __ and a control part the called __
IP
speech degradation
data part - RTP Control Protocol (RTCP).
RTP timestamps - jitter
28. Simplify the router - use H.323 gatekeeper or voice managers to avoid __ __
echo tail - 25
tandem compression
40 - 20 - 8 - 12
person - computer
29. __ Kbps low-delay variation of CELP voice compression 16 kbps
G.728
adaptive differential pulse code modulation (ADPCM) - G.726 - 32
payload field - lower
CRTP
30. Preferred codec for skype - PC to phone apps - A free speech codec suitable for robust voice communication over IP.
VAD - bandwidth - 50
IP - RTP - UDP
iLBC
Propagation delay
31. __by default - sends two 10-ms G.729 speech frames in every packet - If you send more __ frames you put in a packet the fewer ___ you require but if you loose a packet the more __ you lose
last packet - voice
ends - begin - background noise - signal-to-noise threshold
PCM - speech - header - information
IP/RTP/UDP - delay - quality - constrained
32. You stop Echo in a PSTN by __ __ and is done in __ which is located on each __
echo cancelers - software - DSP
Handling delay - queuing delay
Propagation delay
PCM - speech - header - information
33. __ is an _ measurement of voice quality and the __ measures the voice
QoS
CRTP
PSQM - objective - computer
software - dynamic - RTP
34. __ __ occurs when you have more than one compression/decompression cycle for each phone call and Voice degradation occurs
<1%
40 - 20 - 8 - 12
tandom encoding
begins - front-end speech clipping.
35. __ Describes a compression technique that you can use to compress ___or other __ signal components of multimedia service at a low bit rate - MP-MLQ provides greater quality at __ Kbps - CELP provides flexibility at __Kbps
7 - compressed
G.723.1 speech or audio - 6.3 - 5.3
sizing
Propagation delay
36. PSQM was developed to 'hear' impairments caused by __ and __ and not packet loss or jitter
MOS - subjective -1 - 5
sequence information - time-stamping
echo cancelers - software - DSP
compression - decompression
37. This adaptation of jitter buffer __ is effective in compensating for delays.
continuous media - timing reconstruction
sizing
Handling delay - queuing delay
G.711 - PCM - PSTN or PBX(voip networks)
38. __ is a __test given to listeners. The listeners give each sample of speech material a rating of __ (bad) to __ (excellent)
MOS - subjective -1 - 5
RTP is Realtime Transport Protocol - delay sensitive
groups payload - qos - combining
IP
39. Satellite transmission takes approximately __ ms for a transmission to reach the satellite and another __ ms for it to come back down to Earth. This results in a total delay of __ ms.
purchase leased lines - purchase VPN and use access code - OR put voice on data network
speech degradation
7 - compressed
250 - 250 - 500
40. RTCP provides support for real-time conferencing of __ of any size within an Internet - does not send __ - offers __and supports __ media streams
continuous media - timing reconstruction
sequence number and timestamp
groups payload - qos - combining
VAD - bandwidth - 50
41. __ protocol that carries audio and video packets - is the standard for transmitting__ __traffic across packet-based networks
IP/RTP/UDP - delay - quality - constrained
software - dynamic - RTP
PSQM - objective - computer
RTP is Realtime Transport Protocol - delay sensitive
42. Another compression method used often is ____ . A commonly used instance of this is ITU-T __ - which encodes using 4-bit samples - giving a transmission rate of __ Kbps.
jitter buffer
last packet - voice
adaptive differential pulse code modulation (ADPCM) - G.726 - 32
ends - begin - background noise - signal-to-noise threshold
43. Is the amount of time it takes to actually place a bit or byte onto an interface. Its influence on delay is relatively minimal.
Serialization delay
RTP is Realtime Transport Protocol - delay sensitive
Propagation delay
ends - begin - background noise - signal-to-noise threshold
44. In an unmanaged - congested network - ___delay can add up to two seconds of delay (or result in the packet being dropped). This lengthy period of delay is___ in almost any voice network. delay)
queuing - unacceptable
echo tail - 25
source codecs
iLBC
45. Proxy server is not required in an __ based system
IP
sequence number and timestamp
adaptive differential pulse code modulation (ADPCM) - G.726 - 32
Jitter - interarrival - packet-based
46. Is the variation of packet interarrival time.
sequence information - time-stamping
queuing - unacceptable
jitter
last packet - voice
47. It has a large header of __ bytes - Size of headers IP/RTP/UDP
CRTP
7 - compressed
Handling delay - queuing delay
40 - 20 - 8 - 12
48. ___describes CELP compression that enables __ to be coded into _ Kbps streams;
last packet - voice
7 - compressed
G.729 - voice - 8
Serialization delay
49. The problem with VAD is detecting when speech __. This is known as__ Usually - the person listening to the speech does not notice this cut off because it did not record and transmit any codec.
sequence information - time-stamping
begins - front-end speech clipping.
waveform codecs
G.711 - PCM - PSTN or PBX(voip networks)
50. __ the 64 Kbps __ voice coding technique - This is used for the digital voice delivery in the __ or __
Propagation delay
concealment strategy
adaptive differential pulse code modulation (ADPCM) - G.726 - 32
G.711 - PCM - PSTN or PBX(voip networks)