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VOIP
VOIP from Devry
86
Computer Science
Undergraduate 2
08/28/2007

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Cards

Term
2. ____________ are all systems and capabilities necessary to mange, process, transport and use information as a resource in the organization
Definition
C. Management Information Systems
Term
1. With a no right-of-permit required, _________ is great for building-to-building communications within a city
Definition
C. Microwave
Term
3. True or False: The military use of technology often precedes the commercial and personal application of it
Definition
True
Term
4. A quantitative measure of the quality or fidelity of an analog voice signal is _______________
Definition
A. Signal to Noise ratio
Term
5. What is MTBF/(MTBF + MTTR), where MTBF=Mean Time Between Failure; MMTR= Mean Time to Repair? _______________
Definition
A. Availability
Term
6. In the more detailed communications model, we may encode to _________________ (3)
Definition
A. Accommodate the limitations and characteristics of the channel
B. Provide security
C. Provide error detection and or correction
Term
7. True or false: The best way to maintain synchronization in digital telephone systems is to use the PBX’s own internal clock and not the incoming T1 trunk clock?
Definition
False
Term
8. True or false: As a signal travels down a fiber optic cable it experiences attenuation?
Definition
False
Term
9. Any unwanted signal or other source of electromagnetic energy, natural or man-made, which interferes with desired signal reception is known as _________________
Definition
C. Noise
Term
10. A method of in band signaling used by the telephone for providing addressing data to the receiving CO switch or PBX is _________
Definition
A. Dual Tone Multiple Frequency
Term
11. A __________ is a group of interrelated and interdependent parts working together to achieve a common goal
Definition
B. System
Term
13. _________ stands for cycles per second or the number of repetitions that occur within a second of time.
Definition
A. Hertz
Term
14. True or false: Full DS0 throughput of 64Kb/s is not achievable with dial up modems because of the additional overhead required for signaling______________?
Definition
True
Term
15. _____________ is a means for providing higher-quality communications on a channel or circuit by adjusting parameters, thus reducing noise.
Definition
C. Line conditioning
Term
16. Another name for a Class 4 office in the PSTN is a __________.
Definition
C. Toll Office
Term
17. _________ is an example of a PBX feature in which the outgoing trunk selected is based on specific operational requirements
Definition
A. Least Cost routing
Term
18. What is used to interconnect switching systems? ________________
Definition
C. Trunks
Term
19. True or false: The voice digitization process within a switch allows for excess signal frequencies to be included in the voice band to accommodate equipment limitations, these frequencies form the guard band
Definition
True
Term
20. True or false: Coaxial cable media is superior to all physical media used in telecommunications in the areas of attenuation and noise
Definition
False
Term
21. True or false: Digital trunking is superior to analog trunking for long-distance telephony because digital trunks are less susceptible to noise degradation than analog?
Definition
True
Term
22. A __________ line is a telephone service provider bulk pricing package for long distance service?
Definition
C. WATS
Term
23. _______ services are PBX services offered by a common carrier
Definition
A. Centrex
Term
24. When launching light into a fiber optic cable, in order to get total internal reflection, one must be sure the angle of the light entering the cable is _______ _______ the critical angle
Definition
B. Greater than
Term
25. _________ circuits use light as the data carrier on a transparent media
Definition
B. Photonic
Term
26. In its simplest form, _________ is the technology in which a PBX routes a call based on the CallerID signal while accessing the caller’s digital file and linking that to the operator responding to the call.
Definition
A. CTI
Term
27. POTS is a circuit switched technology, while ________ is a packet switched.
Definition
C. VOIP
Term
28. ______________ was the method used by the PSTN to carry voice conversations prior to the development of Time Division Multiplexing
Definition
A. Frequency Division Multiplexing
Term
29. The main advantage(s) of Centrex versus installing a PBX within the customer premise is __________.
Definition
A. Smaller physical footprint
B. Lower initial investment
C. Lower operating costs
Term
30. When digital signals are sampled by decision circuitry within the PSTN, the ______ of the pulse is processed where ISI and noise effects are minimized
Definition
C. Center
Term
31. True or false: Fiber optic circuits are the easiest and least expensive to splice and/or patch.________
Definition
False
Term
32. True or False: In general, Broadband systems typically utilize an analog path that is frequency division multiplexed to create several channels.___________
Definition
True
Term
33. Fiber optic circuits use a ________ at the sending end of the signal path.
Definition
C. LASER diode
Term
34. ___________ Communications employ signals in which the transmitted signal rate is much larger the information rate.
Definition
C. Broadband
Term
35. Satellite communications have mostly been abandoned in favor of terrestrial carriers for voice communications primarily because of _________.
Definition
A. Propagation delay
Term
36. True or false: 4G Cellular communications can provide data rates upwards of 100 Mb/s.
Definition
True
Term
37. __________ is a fiber optic transmission technique that employs multiple light wavelengths to transmit data.
Definition
A. Dense Wave Division Multiplexing(DWDM)
Term
38. True or false: HDTV can be in the analog or digital environment. _________
Definition
True
Term
39. Within Mobile Communication networks, the ________ provides the interface between the cell site and the PSTN
Definition
B. MSC
Term
40. True or false: Cellular phones do not receive a dial tone from the PSTN, they generate it themselves internally._________
Definition
False
Term
41. Cellular telephony can provide a very large number of users with access to the network without running out of voice channels or network bandwidth because of __________ reuse
Definition
A. Frequency
Term
42. True or false: The environment of a system is that part which impacts or influences the system, but over which the system has minimal or no control._________
Definition
True
Term
43. The planning function of voice systems management supports three levels, which are Operational, Tactical and __________.
Definition
Strategic
Term
44. Security considerations within the telecommunications system realm takes into account the aspects of encryption, passwords, firewalls and _________.
Definition
Access
Term
45. With respect to the four objectives of user satisfaction in network management ________ is always the most critical and important
Definition
Reliability
Term
46. True or false: The useful lifespan of telecommunications equipment is increasing at an amazing rate._______
Definition
False
Term
47. Full satellite communications’ earth coverage can be achieved by using _______ satellites.
Definition
3
Term
48. Satellites most commonly used for voice and data service are the _________ type, at 22,300 mile orbits.
Definition
B. Geosynchronous
Term
49. Cellular telephony requires base station towers to be placed, on average, ________ apart. This will vary from urban to rural areas
Definition
3 Miles
Term
True or False: Initial Internet telephony had problems with reliability and fidelity due to limitations in bandwidth
Definition
True
Term
The three principal areas in which the IETF worked to improve network reliability and fidelity were Directory Services, Transport Protocols and ______
Definition
Audio codec format
Term
Reflection of the speaker’s voice when he/she speaks into the IP telephone handset or headset is known as ________
Definition
Near end echo
Term
True or False: In order for VoIP to be viable it must offer or approach the Quality of Service customers are accustomed to on the PSTN
Definition
True
Term
The VoIP call control protocol known as a text based protocol used for establishing and controlling multimedia sessions between two or more endpoints is ______. (s21voip)
Definition
SIP
Term
__________ defines how to handle voice, data & video over regular telephony networks.
Definition
H.324
Term
________ is the switch to switch signaling network used to connect and bill calls across the PSTN
Definition
SS7
Term
True or False: Traditional telephony isn't scalable like VoIP because it isn't software-driven like VoIP.
Definition
True
Term
A __________ picks up where a feasibility study leaves off and has a specific objective of providing a requirement specification as its output.
Definition
Systems Analysis
Term
Defined during the planning stages and refined throughout the life cycle of the system, the ________ reflects the technical strategy
Definition
Architecture
Term
Defined during the planning stages and refined throughout the life cycle of the system, the ________ reflects the technical strategy
Definition
Architecture
Term
As a set of mandates and guidelines from the top of the firm, ___________ is the specific guidelines for execution of a strategy
Definition
Policy
Term
In establishing a project, some sources of requests for projects are ___________.
Definition
Customers
b. Technology vendors
c. Governmental agencies
Term
___________ is defined as a diagrammatic technique employed to document the system in terms of users, data, and processing locations. (S20)
Definition
Network Modeling
Term
In terms of the Cost Estimate Variance by SDLC Phase, which of the following has the greatest cost variance? ______
Definition
Feasibility analysis
Term
True or False : As a packet-switched or connectionless network, the Internet decreases the chances of packet loss for a voice call
Definition
False
Term
ITU’s H.320 standard defines the protocols for transporting voice, data and video over _______.
Definition
b. ISDN networks
Term
In the H.323 protocol, __________ provides the actual voice media transport
Definition
RTP
Term
Cisco’s _________ is a proprietary protocol used between Cisco’s Call manager and Cisco IP Phones
Definition
SCCP
Term
When an IP phone is not sending voice frames within an IP packet because the speaker is not talking, the silence suppression function causes the phone to generate ________.
Definition
Comfort Noise
Term
In the H.323 protocol, __________ provides the actual voice media transport control
Definition
RTCP
Term
An example of a high compression codec from the list below would be _______.
Definition
G.723
Term
In the near term, the market segment expected to be the biggest driver for VoIP telephony is __________.
Definition
e. Small office/home office(SOHO) customers
Term
24) The public Internet transports voice calls reliably and with high quality principally because ____________. 3
Definition
a. Standards are established for differentiating and expediting voice payloads
b. Manufacturers produce higher-quality, lower cost audio codec technology
c. Various technologies deliver greater backbone-network and subscriber-access speeds
Term
25) The project team should be composed of members of groups who have a vested interest in the outcome of the project, known as ________.
Definition
c. Stakeholders
Term
26) True or False: SIP is modeled after the TCP/IP Simple Mail Transfer Protocol (SMTP) and HTTP operating at the OSI application layer
Definition
True
Term
27) RTP has no mechanisms for ensuring on time delivery of packets so ________ is ratified and implemented in routers to establish requested transmission paths and QoS
Definition
RSVP
Term
28) The __________ ensures packet hasn’t been altered in any way during transmission, verifying identity of the sender
Definition
c. Authentication Header
Term
29) In order to provide improved voice quality in IP Telephony, voice endpoints, gateways or both may employ a _________ to smooth out packets arriving at different rates potentially due to network congestion
Definition
c. Jitter Buffer
Term
30) H.323 includes the G.711 codec and the _____ audio codec operating at 7.9 kb/s
Definition
a. G.729
Term
31) True or False: RTCP provides in band control information for RTP traffic
Definition
False
Term
33) The __________ is a subjective measure of quality and fidelity of a voice codec as determined by skilled, trained human listeners
Definition
b. Mean Opinion Score
Term
34) The___________ is a part of the IPSec protocol that follows the IP header or Authentication Header and encrypts the actual payload data.
Definition
a. Encapsulating Security Protocol
Term
35) True or False: G.711 uses one of two digitizing scales: mu law or A-law (mu law is the US standard, each requires 32 kb/s)
Definition
False
Term
36) The _________, as part of the CPE, provides the separation of the incoming T1 data stream into data networking and voice networking components
Definition
CSU/DSU
Term
38) The line encoding format of the T1 carrier for maintaining bit sync is known as _______.
Definition
a. Binary Eight w/ Zero Substitution
Term
39) The T1 Specification mandates a certain pulse density on the line so both ends of carrier stay synchronized. One of those requirements is that there be an overall 1’s density ______ %.
Definition
12.5%
Term
True or False: Robbed bit signaling is an example of in-band signaling used on the T1 carrier
Definition
True
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