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






2. You hear your own voice in the background ( 4wire)






3. RTCP provides support for real-time conferencing of __ of any size within an Internet - does not send __ - offers __and supports __ media streams






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






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






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






7. PCM and ADPCM are examples of __ __






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






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






10. 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






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






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






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






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






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






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






17. VAD problems in determining when speech __ and __ - and in distinguishing speech from __ __. Its also known as __ __ __ __






18. __ __ conceals interarrival packet delay variation.






19. __ is not wasting __ when there is no sound to transmit. At least __ % is wasted






20. __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






21. 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.






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






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






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






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






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






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






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






29. 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.






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






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






32. 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






33. Who scored highest in the MOS






34. 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






35. 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.






36. This adaptation of jitter buffer __ is effective in compensating for delays.






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






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






39. 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)






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






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






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






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






44. When companies merge make sure you configure the __ __






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






46. 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.






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






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






49. You stop Echo in a PSTN by __ __ and is done in __ which is located on each __






50. Propagation delay in conjuction with handeling delay can cause noticeable