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Voice Over IP Test Answers

VOIP - Voice Over Internet Protocol, Upwork called it Voice Over IP and it does have test for it's freelancers. Here in this post, you will find most recent test questions and correct answers of Upwork Voice Over IP test for Networking category. Search your desired answers of the test questions by pressing Ctrl + F button.
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1. Which of the following are the major VoIP protocols?
 Answers: • SIP --or--- • H.323 --or--- • MGCP --or--- • RTP --or--- • RTCP
 
 2. What are the three main steps required in the analog-to-digital conversion process?
 Answers: • Encoding --or--- • Sampling --or--- • Quantization
 
 3. What are the three elements of a security policy necessary for a VoIP network?
 Answers: • Transport Security --or--- • Data Security --or--- • Network Security
 
 4. Which of the following are types of address signaling?
 Answers: • Pulse dialing --or--- • DTMF
 
 5. Which of the following signaling protocols can be used with gateways over a VoIP network?
 Answers: • SIP --or--- • H.323
 
 6. Which of the following provide transport security by using encryption, data integrity and data authentication?
 Answers: • VPNs -- or --- • IPSec
 
 7. Which of the following protocols are assigned ports for each voice call?
 Answers: • RTP in transmit direction -- or -- • RTCP in transmit direction
 
 8. Through which protocols can VPNs be implemented at layer 2?
 Answers: • PPTP -- or -- • L2TP
 
 9. Which of the following are the major framing standards used for Channel Associated Signaling (CAS) by T1?
 Answers: • Super Frame (SF) --or -- • Extended Super Frame (ESF)
 
 10. Which of the following services are provided by Real-time Transfer Protocol(RTP)?
 Answers: • Time stamping --- or --- • Acknowledgements
 
 11. Which of the following are voice compression techniques?
 Answers: • Waveform algorithms -- or -- • Encoding algorithms
 
 12. Which of the following is used by an exchange to convert analog audio to digitized audio?
 Answers: • SS7
 
 13. Which of the following signaling protocols is based on the ISDN Q.931 standard?
 Answers: • SS7
 
 14. How many voice conversations are possible on an E1 line simultaneously?
 Answers: • 30
 
 15. What is the full form of 3DES?
 Answers: • Triple Data Encryption Standard
 
 16. According to the OSI model, which layer performs the function of transforming bits of data into electrical signals and sending those signals across the media?
 Answers: • Physical
 
 17. What is the full form of BGP?
 Answers: • Border Gateway Protocol
 
 18. How many bits are there in a Class B address in Net ID (Network portion) and Host ID (Host Portion) fields by default?
 Answers: • Net ID=16 bits & Host ID=16 bits
 
 19. What is the full form of POTS?
 Answers: • Plain Old Telephone Service
 
 20. What is the full form of L2TP?
 Answers: • Layer 2 Tunneling Protocol
 
 21. Which of the following is responsible for electrical echo on telephone networks?
 Answers: • Incorrect voltage
 
 22. State whether true or false:
 Stateful firewalls do not remember the previous traffic that has occurred earlier in the session
 Answers: • False
 
 23. What are the functions of Call Control?
 Answers: • All of the above
 
 24. Which of the following is the most common trunk signal type used by E&M signaling?
 Answers: • Wink-start
 
 25. What is the range of the frequency of a telephone channel?
 Answers: • 300 Hz to 3400 Hz
 
 26. What is the full form of CCS?
 Answers: • Combined Channel Signaling
 
 27. Which of the following is one of the most important things common in all IP phones?
 Answers: • None of the above
 
 28. What do you call a medium which allows multiple channels?
 Answers: • Multi mode
 
 29. Which of the following methods is most commonly used to remove echo in telephone networks these days?
 Answers: • All of the above
 
 30. What is the minimum bandwidth required for VoIP to deliver high quality services?
 Answers: • 64 kbps
 
 31. According to the ITU standard G.114, what is the maximum delay acceptable for high quality voice?
 Answers: • 150 ms
 
 32. Which of the following classes are used for host addressing?
 Answers: • All of the above
 
 33. What is the function of D (Data) channel in ISDN?
 Answers: • It is used for carrying signaling information
 
 34. Which TCP port number is used by H.323 protocol for call setup?
 Answers: • 5060
 
 35. What is the path of wires that connect the subscriber's telephone to the telephone company's switch located at the latter's central office known as?
 Answers: • Trunk
 
 36. Which of the following can be used to hide internal network addresses and allow several computers on LAN to simultaneously share the router's global IP address?
 Answers: • NAT
 
 37. Which of the following VoIP protocols define end-to-end call signaling methods?
 Answers: • SIP
 
 38. Which of the following is the reason for using UDP instead of TCP for voice transmission?
 Answers: • UDP is fast as compared to TCP
 
 39. Which of the following has the correct sequence (from the lowest layer to the highest)?
 Answers: • Physical, Data Link, Network, Transport, Session, Presentation, Application
 
 40. What is the full form of DSL?
 Answers: • Digital Subscriber Line
 
 41. State whether true or false:
 QSIG is implemented on PRI interfaces only.
 Answers: • True
 
 42. Which of the following protocols is used in a VoIP call at the application layer of the TCP/IP model?
 Answers: • RTP
 
 43. For which of the following services is SS7 responsible?
 Answers: • All of the above
 
 44. State whether true or false
 VoIP runs only on the internet. It cannot run on any other network.
 Answers: • False
 
 45. Which of the following are examples of CCS?
 Answers: • SS7
 
 46. Which of the following devices is used to physically connect all network devices like PCs, IP phones etc. to the LAN?
 Answers: • Switch
 
 47. Which of the following are ITU standards for voice compression?
 Answers: • G.711
 
 48. What is a soft phone?
 Answers: • It is a software that works on a laptop, desktop or a pocket PC
 
 49. On which of the following IP enabled devices can VoIP telephone services work?
 Answers: • All of the above
 
 50. What is the full form of DPNSS?
 Answers: • Digital Private Network Signaling System
 
 51. Which of the following VoIP protocols is an emerging standard for PSTN gateway control?
 Answers: • MGCP
 
 52. How many bits are there in a MAC address?
 Answers: • 48 bits
 
 53. Is it possible to transport fax and modem traffic over a VoIP network?
 Answers: • Yes
 
 54. State whether true or false:
 RTP (Real-time Transport Protocol) requests retransmission if a voice packet is lost.
 Answers: • False
 
 55. Which of the following signaling protocols is used in a common channel to signal all other channels in ISDN?
 Answers: • Q.931
 
 56. Between Asymmetric and Symmetric transmissions, which statement is true of Symmetric transmission?
 Answers: • In Symmetric transmission, the upstream data rate is the same as the downstream data rate
 
 57. What is the full form of SS7?
 Answers: • Signaling System 7
 
 58. Which of the following is a telephony signaling protocol suite used to set up most of the world's PSTN calls?
 Answers: • SS7
 
 59. Which of the following modes of delivery are supported by IPsec?
 Answers: • All of the above
 
 60. Which of the following cables is mostly used in traditional telephones?
 Answers: • Copper wire
 
 61. What is the full form of TDM?
 Answers: • Time Division Multiplexing
 
 62. Which protocol provides end-to-end delivery services for data that requires real-time support such as interactive voice and video?
 Answers: • Real-time Transport Protocol (RTP)
 
 63. What is the full form of PSTN?
 Answers: • Public Switched Telephone Network
 
 64. On which layer of the OSI model does TCP & UDP work?
 Answers: • Transport Layer
 
 65. Which of the following protocols does VoIP use at the transport layer of the TCP/IP model?
 Answers: • SMTP
 
 66. What is the length of IP v4 addresses (in bits)?
 Answers: • 32 bits
 
 67. Is it possible for a POTS line running broadband DSL service to support VoIP telephony in the home?
 Answers: • No