Department of Computer Science & Technology 2014

Transcription

1 Unit 1. Wireless Telecommunication Systems and Networks Short Questions 1. What is Electromagnetic spectrum? 2 State the purpose of Induction. 3. What is the range of Radio Frequency? 4. What are two parameters of signal? 5. Define Telecommunication. 6. List four categories of networks. 7. What do you understand by circuit-switched connection? 8. State the relation between wavelength and frequency. 9. List out three application of the wireless network. 10 What is QAM? 11. What is the function of trunk distribution frame? 12. PSTN interoffice call is made through which line? Long Questions 1. What are the elements in a SS7 signalling network? If we compare a SS7 signalling network with the IP network, which elements are unique and which elements are similar? 2. What is Virtual Private Network? Why is it called virtual? How is it different from a private network? 3. Compare and contrast early and latest telecommunication system in terms of signalling? 4. Observe the below diagram, identify the name of the components and write name of component in given boxes. 5. For a city there are two local telephone exchanges are namely Exchange 1 and Exchange 2 respectively. If the user Amit from Exchange 1 calls to user Pratik located in 1

2 Exchange 2, describe how the call is setup? Also state component involve to establish the call. 6. Identify the component of SS7 which is responsible for exchange voice signalling information in the form of data packets. Also Describe dependent component for above mentioned component, Write note in brief. 7. What are the advantages of the cellular approach of achieving mobile communications as compared to the earlier conventional approach? 8. Compare connection less and connection oriented with respect to telephone systems. Multiple Choice Question 1. The situation when both transmitter and receiver have to work in tandem is referred to as. (a) Parallel (b) Serial (c) Synchronous (d) Asynchronous 2. What is used in In-band channel signaling? a) Uses the voice or control information path for signaling. b) Does not use the voice or control information path for signaling. c) Needs no additional transmission facilities. d) Finds it difficult to handle signaling during voice transmission. 3. Which is a circuit-switched network? (a) Telephone (b) SONET (c) Internet (d) Wi-Fi 4. Trunks are the lines that run between. (a) Subscribers and exchange (b) Switching system and power plant (c) Local area network (d) Switching stations 5. Common channel signaling in SS7 is. (a) Out-of-band control channel. (b) In-band control channel. (c) Speech control channel. (d) Both b & c 6. In a DTMF phone, digits are represented by. (a) Frequencies (b) Phases (c) Pulses (d) Codes 7. Signal Transfer Point (STP) exists in. (a) Internet (b) SS7 (c)pdn (d) PSTN 8. In connection oriented architecture. (a) you need to establish communication (b) sometime connection requires (c) connection is not required (d) connection is establish 9. In Telecommunications, PCM is known as, (a) Pulse-case modulation (b) Pure-code modulation (c) Prime-code modulation (d)pulse-code modulation 10. Which component is the interface between local exchanges with signal transfer point? (a) STP (b) SCP (c) SSP (d) RCL 11. IEEE used for. (a) Bluetooth (b) MAN (c) WAN (d) Wireless LAN 2

3 12. AMPS (Advanced Mobile Telephone System) was invented by which country? (a) India (b) United Kingdom (c) United States (d) France 13. Which of these are Digital Cellular Technologies? (a) IS:54 / IS -136 N-America (b) GSM Europe and Asia (c) IS-95 N America (d) All of the above 14. Who is known as father of Radio? (a) Greham bell (b) Macroni (c) Fessden (d) Hertz 15. Combinations of dots & dashes used for alphanumeric characters is known as, (a) Macroni Code (b) Morse Code (c) Hertz Code (d) Hexa Code 16. RCL stands for. (a)remote Computer Link (b) Remote Communication Lab (c) Redundant Communication Links (d) Redundant Call Line 17. Which is the faster way of communication? (a) Twisted pairs (b) Coaxial cables (c) Optical fibre (d) All of above Fill in the Blanks 1. Host to Host delivery of packet is done by layer. 2. DOCSIS =. 3. AM Stands for. 4. Process to process Delivery of packet is done by layer. 5. FM stands for. 6. IP means Protocol. 7. known as father of radio communications. 8. PDN N/W is used to provide services. 9. In broadband cable Systems FN stands for. 10. OSS stands for. 11. PLMN stands for. 12. call is a call between subscriber connected to same exchange. 13. call is a call between subscriber connected to different exchange. 14. CCIS#7 is also known as system. 15. Network connected with each other can form. 16. Telephone companies normally provide voltage to power telephone. True/False 1. Local Exchange & Company office both is same. 2. QAM is a digital modulation technique. 3. SS#7 use out band signalling. 4. Today s existing infrastructure consisting of both PSTN & PDN. 3

4 5. Raw transmission of bits is responsibility of Physical Network. 6. Wireless Access Point is a device that allows computers to access a wired n/w using radio waves. 7. Broadband is a high capacity telecommunication pipeline capable of providing high speed Internet service. 8. Bandwidth refers to the capacity of communication line. 9. QAM is a hybrid form of amplitude and phase modulation. 10. Connection Oriented and Connection less services both are same. 11. Trunk Line is a line which connects a local exchange with another local exchange. 12. Modem Stands for Modulator Demodulator. 13. Internet is network of networks. 14. In internet routers are connected by WAN backbone. 15. Wireless Local Area N/w is popularly known as WLAN. 16. Raw transmission of bits is responsibility of Physical Network. 17. Wireless Access Point is a device that allows computers to access a wired n/w using radio waves. Unit 2. Evolution and Deployment of Cellular Telephone Systems Short Questions 1. What is base station in context of a cellular network? 2. Which component of SS7 is used to interface signal transfer point at local exchange switch? 3. What are forward and reverse channel used in telecommunication system? 4. What is the function of control channel? What are its types? 5. What event triggers an AMPS handoff operation? 6. What two component of AMPS system provide air interface? 7. What is the purpose of release order message sent by AMPS system to mobile phone? 8. What is SID? 9. List two advantages of the use of digital encoding for cellular telephone system. 10. What is hand off? 11. What is the purpose of control-filler message? 12. What are the features of FDMA? 13 Why the second generation communication system was developed? 14. Provide the frequency band for AMPS system. 15. What is transponder? 16. What is the operational frequency band of 1G AMPS system? 17. What is channel spacing? 18. List out at least four order messages used in an AMPS system to control the mobile phone. Long Questions 4

5 1. Write advantages 2G over 1G telecommunication system. 2. Explain how frequency division duplex operation was achieved by first generation cellular system. 3. Write a short note on analog color code and digital color code. 4. Explain the data transfer method over the AMPS forward control channel. 5. Explain the various steps involved in placing a call from: a) Mobile to a Landline phone, b) Landline Phone to a Mobile Phone. 6. Explain the following terms: a) 1G Telephone Systems b) 2G Phone Systems c) 25 G Systems d) 3G Systems. 7. Explain in detail the evolution of wireless communication? 8. Explain the concept of time division multiplexing. 9. Explain different components of AMPS system with necessary diagrams. 10. Give a step by step explanation of AMPS system operation. 11. Explain the initialization process of mobile station in AMPS system. 12. Give short description of different order messages of the AMPS system. 13. Explain the following terms : (i) Pico Cells, (ii) Micro Cells, (iii) Macro Cells. 14. Compare various wireless systems similar to AMPS. 15. What are the fundamental differences between 1G and 2G? 16. Explain the purpose of the AMPS supervisory audio tones. 17. How second generation systems do supports more than one user per channel? Multiple Choice Question 1. AMPS (Advanced Mobile Telephone System) is of a) India b) UK c) North America d) France 2. Which of these are Digital Cellular Technologies a) IS:54 / IS -136 N-America b) GSM Europe and Asia c) IS-95 N America d) All of the above 3. Which multiple access scheme is used in GSM? a) Time Division Multiple Access (TDMA) b) Code Division Multiple Access (CDMA) c) Frequency Division Multiple Access (FDMA) d) A combination of TDMA & FDMA e) A combination of CDMA & FDMA 5

6 4. What is IS 95? a) It is a standard for cellular CDMA technique. b) It is a standard procedure for measuring indoor multipath propagation characteristics. c) It is the 1995 edition of the conference proceedings on Information Systems. d) It is a standard interconnecting base stations. 5. Marconi a) invented a FDMA. b) postulated the existence of electromagnetic waves. c) demonstrated and commercialized the wireless telegraph. d) invented wireless telephony. 6. Downlink is a) From base station to another base station b) From base station to mobile station c) From mobile station to base station d) From mobile station another mobile station 7. SID is used a) to assign frequency to mobile station b) to know where mobile station is on or not c) to determine the mobile station is within home area or in roaming d) 8. to provides the interface between MSC and mobile subscriber. a) Mobile station b) Base station c) MTSO d) PSTN 9. Audit alert message is a) used to inform the mobile phone that there is an incoming call b) used by base station to determine if the mobile is still active in the system c) used to disconnect a call d) used to inform the user that procedural error 10. ESN stands for a) Electrical Subscriber Number b) Electronic Serial Number c) Exact Serial Number d) Effective Subscriber Number 11. GPRS was defined by a) European Telecommunication Standards Institute b) International Telecommunication Union 6

7 c) Open System Interconnection d) Telecommunication Industry Association 12. According to 3G characteristics maximum cell radius for Mega cell is a) km b) 100 km c) km d) <100 km 13. According to 3G characteristics Pico cell subscriber can get data rate of a) 144 kbps b) 384 kbps c) 2 mbps d) > 2 mbps 14. What was not supported in 2G cellular system a) Voice transmission b) Data transmission c) Handoff operation d) Global roaming 15. CDMA cellular system use a digital modulation technique known as a) Time slots b) Spread spectrum c) Both a & b 16. IEEE used for a) Bluetooth b) Wireless LAN c) MAN d) WAN 17. Which transmission mode is used for data communication along telephone lines? a) Parallel b) Serial c) Synchronous d) Asynchronous 18. Time synchronization is necessary in a) FDM b) TDM c) WDM d) Quadrature multiplexing 19. Engaged tone is generated in a) telephone instrument of calling subscriber b) telephone instrument of called subscriber 7

8 c) telephone exchange d) repeater Fill in the Blanks 1. MTSO has been replaced by the. 2. Stream indicates the status of the reverse control channel. 3. FVC stands for. 4. Mobile station is connected to MSC through Station. 5. The channel spacing was set at MHz in AMPS system. 6. The uplink was from to MHz in AMPS system. 7. 1xRTT technology was implemented over MHz CDMA channel. 8. The network element acts as the interface between SS7 network and various databases used in cellular system 9. AMPS system used channel spacing. 10. The was designed to provide packet data services as an overlay system for AMPS cellular system. 11. In 3G system the macro cell have maximum cell radius of km. 12. GSM technology uses to allow up to 8 users per channel. 13. The 4G mobile network will require architecture. 14. The video conferencing and MP3 transfer is possible from genertation. 15. The provides packet data services with full mobility on GSM networks. 16. The is a circuit switch network, while the is a packet switched network. 17. Typical human voice is centred around Hz. True/False 1. Voice is transmitted through Forward Control Channel. 2. Control channel can also be used to transmit voice messages. 3. Release order message is used to disconnect a call. 4. Overhead message information is used to allow mobile stations to perform the initialization task. 5. MTSO is not a component of AMPS system. 6. AMPS system began operation in the 800-MHz band. 7. Downlink is also known as reverse band. 8. In AMPS system when mobile phone is in the idle mode, it do not perform any operation. 9. The AMPS mobile terminated call is initialized by mobile switching centre while mobile originated call is initialized by mobile station. 10. In the older AMPS system mobile station authorization is not performed. 11. The first generation cellular system used analog frequency modulation schemes for the transmission of voice message. 12. The 1G cellular system uses time division multiplexing to increase system capacity. 8

9 13. The AMPS system have more number of control channels than the traffic channels. 14. The GSM, TDMA, CDMA, CDPD are all 2G technologies. 15. In the AMPS system the base station sends data over the forward control channel while the mobile station sends data over reverse control channel. 16. The GPRS was designed to provide voice services at higher data rates. Unit 3. Common Cellular System Components Short Questions 1. Which two elements of a wireless cellular system perform the "air interface" function? 2. What is the function of the transcoder controller? 3. What is the function of visitor location register? 4. What is the function of home location register? 5. What is the function of mobile switching center? 6. What wireless cellular network element or elements provide security functions for the system? 7. What does a cell global identity number corresponds to? 8. The LAI is used for what purpose? 9. Name the two core network elements associated with 3G cellular networks. 10. What is the function of radio network controller? 11. What is the difference between a MSISDN number and an IMSI number? 12. What is the purpose of global title? 13 What is a mobile global title? 14. What is global title translation? 15. What is the last step performed during a call release operation? 16. What wireless cellular network elements are involved in a mobile-originated call? 17. What is the first step performed by the mobile during a call release operation? Long Questions 1. Using the internet, determine the mobile country code of India. 2. Explain the function of a mobile station roaming number. 3. During a mobile-originated call, when is authentication and encryption performed? 4. Explain the step by step process of call release operation. 5. Write a detail note on subscriber devices. 6. Provide the difference between mobile originated call and mobile terminated call. 7. Describe the typical wireless cellular system components with necessary diagram. 8. What is a base station system? What are the components of it? Describe the functions of its components. 9. What is BSC? Explain the functionality of BSC. 10. Explain following terms. a) IMSI b) IMEI 11. What are the steps performed by the mobile during a call release? Explain it in 9

10 detail. 12. What is subscriber device? What is the identification numbers associated with subscriber device? Explain any two in detail. 13. Describe the hardware view of the cellular system. 14. Why there is more than one HLR within PLMN? What advantage it provide? 15. Provide the formation of LAI number. Multiple Choice Question 1. Which of following component of a cellular system performs transcoding and rate adaptation? a) Base Station Controller b) Mobile Switching Centre c) Mobile Station 2. Which of the following technology is considered as the 2G cellular system? a) FDMA b) TDMA c) CDMA 3. Which cellular component performed rate adaptation? a) MSC b) BSC c) TRC d) MS 4. The is a database that stores information about every user that has a cellular service contract with a specific wireless service provider. a) VLR b) EIR c) HLR d) ILR 5. A mobile originated call starts with a request by the mobile for a signaling channel using. a) Common Control Channel b) Dedicated Control Channel c) Broadcast Channel 6. Which of given is not related to SIM Cards? a) ICCID b) IMSI c) PUK d) CSMI 10

11 7. Abbreviate SIM? a) Subscriber Identity Module b) Subscriber Identity Method c) Subscriber Identical Module d) Subscriber Identical Method 8. Busy hour traffic is the a) maximum average simultaneous traffic b) traffic during peak hour c) traffic when all subscribers are engaged d) the duration of maximum calls Fill in the Blanks 1. The is the link between the customer and the wireless network. 2. The handles all the radio interface related functions for the wireless network. 3. The MSISDN = CC + + SN. 4. The LAI =MCC + + LAC 5. The database is used to validate the status of mobile equipment. 6. Triplet = a ciphering key + + a signed response. True/False 1. The subscriber device and end terminals are different. 2. The subscriber device handles all the radio interface related functions for the wireless network. 3. The transcoder controller consists of subsystems that perform transcoding and rate adaptation. 4. Radio base station is directly connected with mobile switching centre. 5. The HLR database temporarily stores information about any mobile station that attaches to a RBS in the area serviced by a particular MSC. 6. The call release operation is always initiated by mobile device or subscriber device. Unit 4. GSM Technology Short Questions 1. What is the standard bandwidth of a GSM channel? 2. Name the three major subsystem of a GSM wireless cellular network. 3. Give the duration of single timeslot of a TDMA frame in microseconds? 4. What is the purpose of the GSM burst training sequence? 5. What is the purpose of flag bit used in normal burst? 6. Which are the two states in a mobile can be? 7. What GSM control channel is specifically tasked with the facilitating of the handover operation? 8. The GSM MS roaming number is constructed according to what numbering plan? 9. What purpose does the TMSI number have? 11

12 10. Define the "attached" condition for a GSM mobile. 11. Define the "detached" condition for a GSM mobile. 12. What is the purpose of periodic location updating? 13 What is the basic difference between intra-bsc handover and inter-bsc handover? 14. What is the basic difference between inter-bsc handover and inter-msc handover? 15. What is the first operation performed by a NA-TDMA mobile upon powering up? 16. List the operations performed during a call setup. 17. Why there is a difference of three timeslots between uplink and downlink TDMA frame? 18. Provide the uplink frequency range for primary GSM-900 band. Long Questions 1. Looking at the HLR/VLR database approach used in GSM - how does this architecture limit the scalability in terms of users, especially moving users? 2. What is the duration of GSM air interface timeslot? Also prove that the overall bit rate over the air interface is approximately kbps for GSM system. 3. Name the main elements of the GSM system architecture and describe their functions. What are the advantages of specifying not only the radio interface but all the internal interfaces of the GSM System. 4. Describe the function of MS and SIM. Why does GSM separate the MS and SIM? 5. The maximum distance allowed by the Timing Advance between the mobile station and base transceiver system in GSM system is 35 km. Justify your answer. 6. Describes the GSM TDMA timeslot. 7. Contrast the GSM hyperframe, superframe, multiframe, and TDMA frame. 8. Provide the structure and use of normal burst and frequency correction burst. 9. What is the function of the GSM access burst? 10. What is the purpose of the GSM dedicated control channels? 11. How does the GSM mobile station know what paging group it belongs to? 12. State the reason behind the delay of three timeslot between uplink and downlink frame. 13. Why are there several types of GSM multiframes? 14. What basic functions are located within the connection management sublayer? 15. What is location updating? Explain the IMSI detach and attach location updating. 16. Explain the network switching system (NSS) of GSM network in detail. 17. Contrast the required bandwidth requirements of AMPS, GSM, and NA-TDMA. 18. Explain in detail the concept of GSM TDMA frame structure. 19. What are the two protocol stacks within the MSC node for a GSM system? 20. Show the steps of interrogation operation performed during call setup using a timeline diagram. 21. Explain the authentication operation of call setup using necessary diagram. 22. What is a GSM SIM card? What purpose does it serve? Multiple Choice Question 1. The Primary GSM 900 used to MHz uplink frequency band. 12

13 a) b) c) d) The GSM 900 band has carrier frequencies. a) 240 b) 124 c) 374 d) In GSM cellular system each carrier frequency can be shared up to how many users? a) 2 b) 4 c) 8 d) The total number of channels for GSM 900 is. a) 2992 b) 992 c) The MS is the device that provides the radio link between and. a) GSM subscriber and wireless mobile network b) MSC and BSC c) MSC and RBS 6. In the GSM standard, the MS consisting of which to elements a) mobile equipment and SIM card b) RBS and mobile equipment c) RBS and TRC 7. Which are the two elements of base station system (BSS)? a) a mobile station and a radio base station b) a radio base station and mobile switching centre c) a base transceiver system and the base station controller 8. An RBS in GSM cellular system is consisting of how many BTS that service a standard sectorized cell site? a) 2 b) 3 c) 4 13

14 d) 1 9. The is used by the GSM system to provide number portability to subscriber. a) visitor location register b) home location register c) flexible numbering register d) equipment identity register 10. Which of the following component provide surveillance of the entire network in GSM system. a) Operation and Support System b) Mobile Switching Centre c) Network Switching System 11. Which interface is exists between the BSC and BTS? a) A Interface b) Um Interface c) Abis Interface d) Ater Interface 12. The interface exists in GSM system that have separate units for the transcoder controller and base station controller. a) A Interface b) Um Interface c) Abis Interface d) Ater Interface 13. The maximum distance allowed by the TA between the MS and BTS in GSM system is. a) 35 km b) 35 meter c) 2 km d) 200 meter 14. What is the maximal decimal number that can be accommodated in a byte? a) 128 b) 256 c) 255 d) 512 Fill in the Blanks 1. For GSM cellular system the air interface consists of channels that have a frequency separation of khz. 2. The GSM 1800 band has carrier frequencies. 3. In the GSM standard, the MS consisting of and. 4. The BSC and BTS communicate with each other using protocol in 14

15 GSM cellular system. 5. The NSS will use to redirect messages sent by a GMSC toward a particular HLR to the correct HLR TDMA frame = Timeslots ms Hyperframe = Superframes = TDMA frames 8. The is used by GSM system to reduce the number of steps required for call setup. True/False 1. Hand over occurs when an inactive mobile station changes cells. 2. The GSM cellular system supports subscriber's roaming mobility through location updating operation only. Unit 5. CDMA Technology Short Questions 1. What does the term cdmaone stands for? 2. What is the unique aspect of CDMA technology? 3. What ultimately limits the number of users of a CDMA cellular wireless system? 4. What are Walsh codes? 5. What is the length of the CDMA short PN spreading codes? 6. Of what use is the CDMA frame format in the context of paging channel operation? 7. What is the difference between the CDMA soft handoff and the CDMA softer handoff? 8. How many additional supplemental code channel may be supported by IS-95B? Long Questions 1. If the basic CDMA signal bandwidth is 1.25 MHz, why are allocated CDMA channels only separated by 50 KHz spacing in Band Class 0? 2. How can additional CDMA system capacity be achieved? 3. What is the function of the interworking function node in a 2G CDMA system? 4. What is the function of the mobile positioning system? 5. In a cdma2000 system, what is the function of the packet core network? What are its main components? 6. What is the function of the home agent in a cdma2000 system? 7. What is the function of the packet data serving node in a cdma2000 system? 8. How does the use of spreading codes increase signal bandwidth? 9. Describe how different base stations in a CDMA system are able to be differentiated by mobile stations. 10. Describe the generation of the IS-95 CDMA pilot channel. 11. Describe how the CDMA traffic channel is also able to provide power control information to the subscriber's mobile device. 12. How does the CDMA system differentiated uplink signals transmitted by different mobiles? 15

16 13. Describe the use of power control groups on the CDMA reverse traffic channels. What purpose do they serve? 14. Describe the three states that a CDMA mobile may be in while in the attached mode. 15. Describe the steps a CDMA mobile goes through in the initialization state. 16. Describe the CDMA soft handoff. Unit 6. Cellular Wireless Data Networks-2.5 and 3G Systems Short Questions 1. Why was CDPD developed? 2. What two new network nodes are needed to implement GPRS operation? 3. What is the purpose of a packet data protocol address in the context of GPRS operation? 4. What is the purpose of the delivery/failure report sent during a mobile originated SMS transfer? 5. Which are the two major components required to provide GPRS service on existing GSM network infrastructure? 6. Which technology is used in Bluetooth for avoiding interference? Long Questions 1. How did 1G cellular wireless systems support data services? 2. Describe the basic difference between 1G and 2G wireless in terms of data services. 3. Contrast packet-switched data transmission to circuit data transmission. 4. Give a short description of a CDPD system. How does it interface with the host AMPS system? 5. Describe the CDPD operation of cell transfer. 6. Why is a new infrastructure needed for GPRS, but not for HSCSD? Which components are new and what is their purpose? 7. Describe the basic operation of GSM GPRS. 8. Describe basic GSM EDGE operation. 9. Describe the basic evolutionary path from GSM to UMTS. 10. What is the basic difference between EMS/MMS and SMS? 11. From a network viewpoint, what is the basic difference between SMS and MMS? 12. Describe the relationship between WAP and MMS. 13. How will the next generation of wireless systems be different from the current 3G technologies? 14. Briefly explain why security mechanisms are becoming increasingly important in wireless networks. 15. Why CDPD was developed? Describe CDPD network architecture in detail. 16. Discuss with necessary diagrams the process of mobile originated and mobile terminated SMS message transfer. 17. How the CDPD network overlays the existing AMPS network to provide data services. 16

17 Multiple Choice Question 1. EDGE networks are a) 2.2 G b) 2.5 G c) 2.75 G d) 3G 2. 3G is a) International Mobile Telecommunications-1998, family of standards b) International Mobile Telecommunications-1999, family of standards c) International Mobile Telecommunications-2000, family of standards d) International Mobile Telecommunications-2001, family of standards 3. Android is an Open Source cross platform OS by a) Microsoft b) Nokia c) Google d) RIM 4. SMS service was first launched in a) 1G b) 2G c) 2.5G d) 3G 17