NCS 20022252010 NCSS 2G 3G SCN OaM 2 2 Practice
Exam
**Question 1.** Which GSM core network element is primarily responsible for
subscriber profile storage and authentication?
A) Mobile Switching Center (MSC)
B) Home Location Register (HLR)
C) Visitor Location Register (VLR)
D) Base Station Controller (BSC)
Answer: B
Explanation: The HLR contains permanent subscriber data, including
authentication keys, and provides this information to the network during call
setup.
**Question 2.** In UMTS architecture, which entity routes user plane data
between the radio access network and external IP networks?
A) Serving GPRS Support Node (SGSN)
B) Gateway GPRS Support Node (GGSN)
C) Radio Network Controller (RNC)
D) Mobility Management Entity (MME)
Answer: B
Explanation: The GGSN acts as the interface between the UMTS packet core and
external packet data networks, handling IP address allocation and routing.
**Question 3.** Which signaling protocol is used to transport SS7 messages over
IP networks?
, NCS 20022252010 NCSS 2G 3G SCN OaM 2 2 Practice
Exam
A) MAP
B) CAP
C) SIGTRAN
D) SIP
Answer: C
Explanation: SIGTRAN provides transport of SS7 signaling over IP using SCTP,
enabling reliable message delivery.
**Question 4.** During a GSM intra‑BSC handover, which component initiates the
handover request?
A) MSC
B) VLR
C) BSC
D) HLR
Answer: C
Explanation: The BSC monitors signal quality and, when necessary, initiates an
intra‑BSC handover to another BTS under its control.
**Question 5.** In GPRS, what does the “PDP Context” define?
A) Voice codec selection
B) Logical channel mapping
, NCS 20022252010 NCSS 2G 3G SCN OaM 2 2 Practice
Exam
C) Packet data session parameters such as IP address and QoS
D) SIM authentication algorithm
Answer: C
Explanation: The PDP Context holds the parameters for a packet data session,
including the assigned IP address and QoS attributes.
**Question 6.** Which modulation scheme is employed by EDGE to achieve
higher data rates compared to GPRS?
A) GMSK
B) 8‑PSK
C) QPSK
D) OFDM
Answer: B
Explanation: EDGE uses 8‑phase shift keying (8‑PSK) instead of GMSK, allowing
three times the bit rate per symbol.
**Question 7.** WCDMA, the air interface for UMTS, operates primarily in which
frequency band?
A) 900 MHz
B) 1800 MHz
C) 2100 MHz
D) 2600 MHz
, NCS 20022252010 NCSS 2G 3G SCN OaM 2 2 Practice
Exam
Answer: C
Explanation: UMTS WCDMA was standardized for the 2100 MHz band in most
regions, providing sufficient bandwidth for high‑rate services.
**Question 8.** What is the primary purpose of power control in CDMA‑based
systems?
A) Reduce handover latency
B) Minimize inter‑cell interference and improve capacity
C) Increase modulation order
D) Allocate frequency channels dynamically
Answer: B
Explanation: Power control adjusts the transmit power of each user to the
minimum needed, reducing interference and allowing more users to share the
same spectrum.
**Question 9.** Which component of the Signaling Control Network (SCN) routes
SS7 messages between different network nodes?
A) Signaling Transfer Point (STP)
B) Mobile Switching Center (MSC)
C) Base Station Subsystem (BSS)
D) Home Location Register (HLR)
Answer: A
Exam
**Question 1.** Which GSM core network element is primarily responsible for
subscriber profile storage and authentication?
A) Mobile Switching Center (MSC)
B) Home Location Register (HLR)
C) Visitor Location Register (VLR)
D) Base Station Controller (BSC)
Answer: B
Explanation: The HLR contains permanent subscriber data, including
authentication keys, and provides this information to the network during call
setup.
**Question 2.** In UMTS architecture, which entity routes user plane data
between the radio access network and external IP networks?
A) Serving GPRS Support Node (SGSN)
B) Gateway GPRS Support Node (GGSN)
C) Radio Network Controller (RNC)
D) Mobility Management Entity (MME)
Answer: B
Explanation: The GGSN acts as the interface between the UMTS packet core and
external packet data networks, handling IP address allocation and routing.
**Question 3.** Which signaling protocol is used to transport SS7 messages over
IP networks?
, NCS 20022252010 NCSS 2G 3G SCN OaM 2 2 Practice
Exam
A) MAP
B) CAP
C) SIGTRAN
D) SIP
Answer: C
Explanation: SIGTRAN provides transport of SS7 signaling over IP using SCTP,
enabling reliable message delivery.
**Question 4.** During a GSM intra‑BSC handover, which component initiates the
handover request?
A) MSC
B) VLR
C) BSC
D) HLR
Answer: C
Explanation: The BSC monitors signal quality and, when necessary, initiates an
intra‑BSC handover to another BTS under its control.
**Question 5.** In GPRS, what does the “PDP Context” define?
A) Voice codec selection
B) Logical channel mapping
, NCS 20022252010 NCSS 2G 3G SCN OaM 2 2 Practice
Exam
C) Packet data session parameters such as IP address and QoS
D) SIM authentication algorithm
Answer: C
Explanation: The PDP Context holds the parameters for a packet data session,
including the assigned IP address and QoS attributes.
**Question 6.** Which modulation scheme is employed by EDGE to achieve
higher data rates compared to GPRS?
A) GMSK
B) 8‑PSK
C) QPSK
D) OFDM
Answer: B
Explanation: EDGE uses 8‑phase shift keying (8‑PSK) instead of GMSK, allowing
three times the bit rate per symbol.
**Question 7.** WCDMA, the air interface for UMTS, operates primarily in which
frequency band?
A) 900 MHz
B) 1800 MHz
C) 2100 MHz
D) 2600 MHz
, NCS 20022252010 NCSS 2G 3G SCN OaM 2 2 Practice
Exam
Answer: C
Explanation: UMTS WCDMA was standardized for the 2100 MHz band in most
regions, providing sufficient bandwidth for high‑rate services.
**Question 8.** What is the primary purpose of power control in CDMA‑based
systems?
A) Reduce handover latency
B) Minimize inter‑cell interference and improve capacity
C) Increase modulation order
D) Allocate frequency channels dynamically
Answer: B
Explanation: Power control adjusts the transmit power of each user to the
minimum needed, reducing interference and allowing more users to share the
same spectrum.
**Question 9.** Which component of the Signaling Control Network (SCN) routes
SS7 messages between different network nodes?
A) Signaling Transfer Point (STP)
B) Mobile Switching Center (MSC)
C) Base Station Subsystem (BSS)
D) Home Location Register (HLR)
Answer: A
