Test your basic knowledge |

CCNA Voice - 3

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. __is characterized as the amount of time it takes for speech to exit the speaker's mouth and reach the listener's ear.






2. Is the amount of time it takes to actually place a bit or byte onto an interface. Its influence on delay is relatively minimal.






3. RTP consists of a __ __ and a control part the called __






4. Proxy server is not required in an __ based system






5. The difference between when the packet is expected and when it is actually received is __. - exists only in __ ___ networks






6. PCM and ADPCM are examples of __ __






7. 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.






8. 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






9. 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






10. __ 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






11. __ __ replays the last packet received






12. PSQM was developed to 'hear' impairments caused by __ and __ and not packet loss or jitter






13. __ __ occurs when you have more than one compression/decompression cycle for each phone call and Voice degradation occurs






14. __ describes __ coding at __ - __ - __ and __ Kbps; you also can interchange ADPCM voice between packet voice and public phone or PBX networks






15. How do you fix queuing delay - you would add






16. 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.






17. Using G.729 - just __ conversions from D/A cause the MOS score to decrease rapidly but __ is less resilient






18. RTP uses the __ __ to determine whether the packets are arriving in order - and it uses the __ __ information to determine the interarrival packet time (jitter).






19. __ is an _ measurement of voice quality and the __ measures the voice






20. 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)






21. What do you use to compress RTP header to 2 or 4 bytes






22. 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.






23. Preferred codec for skype - PC to phone apps - A free speech codec suitable for robust voice communication over IP.






24. __ Kbps low-delay variation of CELP voice compression 16 kbps






25. ___ ___ are used within Cisco IOS Software to determine what level of ___ - if any - exists within the network.






26. 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.






27. To reduce the overall ___ overhead introduced by the 54-byte header - multiple voice samples can be packed into a single Ethernet frame to transmit. Although this can increase the voice ___ - increasing this count can improve the overall voice___ - e






28. How many times can a digital to analog conversion in my network and PSTN total network happen - __ speech is less robust conversion






29. __ recommends no more than __ms delay one-way transmission






30. How does G.729 header go __/__/__






31. To make audio and video work with RTP what do you need. 2 things






32. __ builds in some reliability to the connectionless __ protocol - enables reliability with out using the overhead of __ - what protocol send multiples of the same packet __






33. Is the variation of packet interarrival time.






34. 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.






35. If a packet is lost What is replayed? packet loss is common in data networks but not in __






36. On a voip link What is the max packet loss






37. Voice samples are packed into the___ ___ of a UDP/RTP packet and thus the network header overhead would be __.






38. 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).






39. A __ can trick the human ear into perceiving a higher-quality voice - but a __ cannot be tricked.






40. 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)






41. 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.






42. Time of day of highest calls on circuit focus those on the __






43. ___describes CELP compression that enables __ to be coded into _ Kbps streams;






44. __ __ conceals interarrival packet delay variation.






45. __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






46. __ the 64 Kbps __ voice coding technique - This is used for the digital voice delivery in the __ or __






47. Bob@nextdoorneighbor.com is a __ entry but coverts then to an __ address






48. It has a large header of __ bytes - Size of headers IP/RTP/UDP






49. Caused by the length a signal must travel via light in fiber or electrical impulse in copper-based networks.






50. __ protocol that carries audio and video packets - is the standard for transmitting__ __traffic across packet-based networks