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






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






3. 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).






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






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






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






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






8. __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






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






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






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






13. 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.






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






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






16. Is the variation of packet interarrival time.






17. 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.






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






19. 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.






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






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)






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






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






24. 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






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






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






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






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






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






30. 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.






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






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






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






34. __ __ replays the last packet received






35. 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






36. 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.






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






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






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






40. What are 3 things you can do if they want to implement a corporate dial plan






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






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






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






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






45. 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.






46. Who scored highest in the MOS






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






48. PCM and ADPCM are examples of __ __






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






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