S38.115/Spring 2003
Prof. Raimo Kantola:
Possible questions in exams
Initial list was inherited from S38.120. List has been updated based on this years’ slides. You can use this as a reading guide.
The list is meant as a guideline for preparing to the exam. For the exam
itself the list is not necessarily exhaustive.
1. Types of networks and the layering of functionality in
networks
2. Addressing in different telecommunications networks.
3. Compare the similarities and
differences in networking architectures and functioning principles of
PSTN/ISDN and IP for telephony
4. Generations of the Switching systems and their life cycles.
5. Types of traffic in comparison to network hierarchy – define terms such as
incoming traffic and all similar terms
6. Fundamentally, why is signalling needed?
7. Give the pricipal structure of a signaling system as a
state machine using both algebraic and graph representation for the state
machine. Describe also the signaling flow chart method and compare it to the
state machine method as a description and specification method.
8. Classify PSTN signaling systems and tell about their development roadmap.
9. Subscriber line signaling.
10. Principles of R2 signaling.
11. What are the limitations of line associated signaling? How does CCS7 help
to overcome those limitations?
12. Define the terms CCS7 network, point code, link, link set.
13. What are the reliability and real-time requirements for CCS7 ?
14. Describe the functional structure of CCS7.
15. Describe the functional structure of MTP.
16. Define the terms used in MTP: signaling link, link set, signaling route,
signalling route set.
17. Describe the message types in MTP and give the structure of the MTP
information message.
18. Give an example that animates the concept of network in MTP.
19. Describe the addressing mechanisms in SCCP.
20. Global title in SCCP:ssä. Give an example.
21. The advantages and disadvantages of CCS7.
22. Describe the structure of basic access in ISDN and the reference points
defined for the basic access.
21. Basic access activation procedure in ISDN.
22. Describe the algorithm of an HDLC -transmitter and receiver using
pseudocode.
23. Describe the frame structure in the S-interface.
24. Principles of DSS1 signaling and the connection establishment procedure.
25. Principle of voice coding in PSTN and ISDN. How is VOIP different in this respect.
26. Outline methods to measure the voice quality objectively and subjectively. Consider the impact of delay on voice quality.
27. Explain the E-model.
28. Explain the PCM hierarchy.
29. What is the purpose of TCAP, describe also its
structure. Compare TCAP with OSI.
30. Describe TCAP functional principles and operation types.
31. Describe the principle of unstructured dialogue in TCAP.
32. Describe the structured dialogue in TCAP.
33. V5 achitecture and interfaces. Use of V5 signaling and
its impact to competition on the telecom markets.
34. What has to be specified nationally for V5 signaling?
35. V5.1 ja V5.2 interfaces and main type of services for subscribers.
36. Distibution of functions in V5.x specifications.
37. Draw and describer the block diagram and of the V5.1 protocol
arkhitecture.
38. Draw and describe the block diagram of the V5.2 protocol architecture.
39. Describe the use of C-channels in V5 and their control protocol.
40. Implementation of ISDN -signaling in V5.
41. Functional structure and most important messages of the PSTN protocol in
V5.
42. Describe the call-by call connection control in a V5 subscriber access
node.
43. Describe the principles of the V5.2 link control for the access
node to LE links.
44. Describe the mechanisms for call identification in ISUP.
45. Succesfull call setup in ISUP-signaling using a signalling flow diagram.
46. How is the compatibility of consecutive ISUP versions managed?
47. Describe the method of specification for interworking of message based
signaling systems.
48. MAP development phases, compatibility of MAP-versions.
49. Addressing principles of MAP -messages in a GSM-network.
50. Describe the use of TCAP services by MAP.
51. Location management principles and procedures in MAP.
52. Terminating call routing in GSM
53. MSC-to-MSC handover in MAP.
54. Security operations in MAP.
55. Subscriber management operations in MAP (original GSM and GPRS)
56. GSM-supplementary services operations in MAP.
57. USSD-service and its function.
58. GSM short message service from the point of view of MAP.
59. Routing and addressing of short messages over GSM.
60. The goals and phases of CAMEL specifications. Describe also the phase 1
CAMEL-architecture.
61. Originating and terminating call prosedures according to CAMEL.
62. Consider mobility management requirements in GSM and their impact on the mobility management architecture chosen in GSM
63. Describe the tasks of the original GSM Core Network elements and compare them to the tasks of the GPRS core network elements.
64. Explain the concept of the PDP context. Give two examples of usage of a PDP context for a purpose.
65. Describe the MAP support for CCBS.
66. Describe the (prevailing) protocol stack used in IP
Telephony. Define the main functions of each
protocol in the stack.
67. Describe the network scenarios in IP Telephony.
68. Define the factors of Quality of Service in IP Voice. What are the
principal means to maintain and
improve the quality of IP Voice.
69. Describe the functional structure of a voice gateway (equipment and software layers in sending and receiving voice).
70. Discuss packet overhead in IP voice. What can be done to reduce the overhead? Where is that applicable?
71. Describe the RTP protocol. What are the main header fields and functions?
72. Describe the RTCP protocol. Show the information passed in the protocol, explain relation to RTP and the goals of RTCP.
73. What
are the functional entities according to H.323. Define also the main functions
of the entities.
74. List the call modes supported by H.323. Draw an example of a call mode
suitable for a call between
5 parties two of which are connected to a
LAN and three are using a remote network connection.
75. Define the concept of Zone in H.323.
76. Describe the use of addresses in IP Telephony according to H.323.
77. Define the tasks of a gateway and a gatekeeper in H.323.
78. Describe the functions of RAS-signalling in H.323.
79. Describe the principles of call signalling in H.323.
80. Describe the functions of H.245 signalling in IP Telephony.
81. Describe the functions and use of RTP in IP Telephony.
82. Describe the functions and use of RTCP in IP Telephony.
83. Describe the signalling flow for a GK routed (one GK) call signalling procedure according to H.323, show both RAS and call signalling.
84. Compare H.323 and SIP. Point out main architectural and design differences.
85. Application triggering in 3G IMS.
86. 3G IMS network functions and their roles in controlling sessions.
87. 3G IMS architecture, elements and roles of visited and home networks.
88. Role and protocols supported by the HSS in 3G CN.
89. Functional model of a UMTS terminal.
90. Naming according to ENUM, records in ENUM.
91. Use of ENUM, give an example hierarchy and a use example. Discuss also issues open in ENUM.
92. MEGACO – protocol purpose, function and place in the VOIP architecture.
93. COPS – protocol purpose, function and place in the NGN and 3G architecture.
94. Show signal flows for policy decision and enforcement using COPS.
95. SDP – protocol purpose and carried information.
96. Diameter principle architecture, documents and protocol features. Examples of Diameter applications.
97. Describe how Diameter scalability has been enhanced.
98. Diameter element types and the functions supported in each element.
99. Diameter base protocol requests and answers.
100.Diameter/NASREQ application.
101.Diameter/3G multimedia application.
102.Registration and deregistration using Diameter.
103.SIP entities and the basic session invitation procedures in the generic SIP
104.The structure of UA and proxy in SIP, different types of proxies in SIP.
105.SIP message structure.
106.The purpose and use of the main header fields in SIP
107.How are loops prevented in SIP.
108.Use of the PRACK and UPDATE methods in SIP.
109.Functional entities and their capabilities according to 3G SIP
110.Roles of different Session Functions according to 3G IMS.
111.Discuss business threats to 3G IMS.
112.SCTP features and motivation. Why was TCP not enough?
113.SCTP associations and the header structure.
114.Describe association establishment in SCTP.
115.Modes of data transfer in SCTP – sequencing and reliability.
116.SUA features and linkage to SS7.
117.M3UA features, linkage to SS7 and a use example.
118.Layer2 solutions for SS7 over IP. Options, features and a use example.