4G Mobile core and Access n/w planning Flashcards
__________ is the maximum data rate that a single cell can handle
1) spectral efficiency
2) channel capacity
channel capacity
Motivations for LTE
1) move everything to packet-switched domain
2) reduce latency
3) UMTS and GSM has become complex
4) all the above
all the above
3G networks introduce delays of the order of ___ milliseconds for data
applications.
1) 10 milliseconds
2) 100 milliseconds
3) 500 milliseconds
100 milliseconds
EPC stands for
Evolved Packet Core
- is a direct replacement for the packet
switched domain of UMTS and GSM.
It distributes all types of information to the user, voice as well as data, using the packet switching technologies
UTRAN stands for
UMTS Terrestrial Radio Access Network
3GPP work item for core network
1) SAE (system architecture evolution)
2) LTE (long term evolution )
SAE (system architecture evolution)
- LTE is for radio access network
- the whole system with LTE is known as the evolved packet system (EPS)
GPP work item for radio access network, air interface and mobile
1) SAE (system architecture evolution)
2) LTE (long term evolution )
LTE (long term evolution )
- SAE is for core network
- the whole system with SAE is known as the evolved packet system (EPS)
Officially LTE refers only to the evolution of the
1) radio access network
2) air interface
3) mobile
air interface
Despite this official usage, LTE has become a colloquial name for the whole system, and is regularly used in this way by 3GPP.
parameter which expresses the typical capacity of one cell per unit bandwidth
1) spectral efficiency
2) channel capacity
spectral efficiency
the time taken for data to travel between the mobile phone and the fixed network should be less than ___ milliseconds
1) 1 milliseconds
2) 5 milliseconds
3) 10 milliseconds
5 milliseconds
phone should switch from standby to the active state, after an intervention from the user, in less than __ milliseconds
1) 10 milliseconds
2) 50 milliseconds
3) 100 milliseconds
100
milliseconds
LTE is optimized for cell sizes up to ___ km, works with degraded performance up to ___ km and supports cell sizes of up to ____ km
1) 5, 20, 50
2) 5, 30, 80
3) 5, 30, 100
4) 5, 50, 100
5, 30, 100
LTE is optimized for mobile speeds up to ___ km/hr, works with high performance up to ___ km/hr and supports speeds of up to ___ km/hr.
1) 10, 100, 300
2) 15, 120, 350
3) 20, 150, 300
4) 15, 150, 350
15, 120, 350
LTE is designed to work with a variety of different bandwidths, which range from _____ to ______
1) 1 MHz to 10 MHz
2) 1 MHz to 20 MHz
3) 1.5 MHz to 25 MHz
4) 1.4 MHz to 20 MHz
1.4 MHz to 20 MHz
the maximum time required for data to travel across the EPC
1) 10 milliseconds
2) 50 milliseconds
3) 100 milliseconds
4) no requirement
no requirement.
but relevant specification suggests a user plane latency of 10 milliseconds for a non-roaming mobile, increasing to 50 milliseconds in a typical roaming
scenario. adding delay across the air
interface, giving a typical delay in a non-roaming scenario of around 20 milliseconds.
EPC is also required to support inter-system handovers between
1) LTE and earlier 2G and
3G technologies
2) cdma2000
3) WiMAX
4) all the above
all the above
The EPC is designed as a data pipe that simply transports information to and from the user: it is not concerned with the information content or with the application (T/F)
T
The EPC simply transports the voice packets in the same way as any other data stream.
EPC user plane latency in a non-roaming scenario is around
1) 10 milliseconds
2) 20 milliseconds
3) 50 milliseconds
20 milliseconds.
UMTS Handovers
1) Soft
2) Hard
3) Both
Both
LTE Handovers
1) Soft
2) Hard
3) Both
Hard only
Neighbour lists ________ for UMTS and ________ for LTE
1) always required, always required
2) always required, not required
3) not required, always required
4) not required, not required
Always required for UMTS and not required for LTE
IP connectivity is ________ for UMTS and ________ for LTE
1) after registration, after registration
2) after registration, during registration
3) during registration after registration
4) during registration during registration
after registration for UMTS and during registration for LTE
_______ replaces the old Node B / RNC combination from 3G
1) eNodeB
2) gNodeB
3) ngNodeB
Evolved Node B (eNB)
It is the only network element defined as part of EUTRAN
_______ is/are the only network element(s) defined as part of EUTRAN
1) eNB
2) RRH
3) EPC
4) All the above
Evolved Node B (eNB) is the only network element defined as part of EUTRAN
inter-eNB handovers are possible without direct involvement of EPC during this process (T/F)
True.
inter-eNB interface X2 helps this.
MME stands for
Mobility Management Entity
MME features
1) pure signaling entity inside the EPC
2) handles attaches and detaches to the LTE system
3) track the position of idle UEs
4) all the above
all the above
MME features
1) possesses an interface towards the HSS (home subscriber server)
2) signaling coordination to setup transport bearers (LTE bearers) through the EPC for a UE
3) generates and allocates temporary ids for UEs
4) all the above
all the above
_____ generates and allocates temporary ids for UEs
1) EPC
2) MME
3) eNB
MME
_______track the position of idle UEs
1) EPC
2) MME
3) eNB
MME
MMEs can be interconnected via the __ interface
1) S10 interface
2) S11 interface
3) S1U interface
2) X2 interface
S10 interface
eNBs can be interconnected via the __ interface
1) S10 interface
2) S11 interface
3) S1U interface
2) X2 interface
X2 interface
A functionality of the ____is the signaling coordination to setup transport
bearers (LTE bearers) through the EPC for a UE.
1) EPC
2) MME
3) eNB
MME
SGW is controlled by ______ via S11 interface
1) one MME
2) one or more MMEs
one or more MMEs
At a given time, the UE is connected to the EPC via ______
1) a single SGW
2) multiple SGWs
a single SGW
SGW interface towards eNB
1) S10 interface
2) S11 interface
3) S1U interface
2) X2 interface
S1U interface
SGW relays the packet data within EPC via the ____ interface to or from the PDN gateway
1) S10 interface
2) S11 interface
3) S1U interface
2) S5/S8 interface
S5/S8 interface
_________is comparable to GGSN in 2G/3G networks
1) Serving gateway
2) PDN gateway
3) MME
PDN (Packet Data Network) Gateway
A major functionality provided by a ____ is the QoS coordination between the external PDN and EPC
1) Serving gateway
2) PDN gateway
3) MME
PDN gateway
PCRF stands for
Policy and Charging
Rule Function
PDN gateway can be connected via ___ to a PCRF
1) S10 interface
2) S11 interface
3) S7 interface
2) X2 interface
S7 interface
If a UE is connected simultaneously to several PDNs this may involve connections to more than one ____
1) Serving gateway
2) PDN gateway
3) MME
PDN gateway
Physical Cell Identity (PCI) planning
1) PCI = 3SSS + PSS
2) PCI = 3PSS + SSS
PCI = 3*SSS + PSS
PSS: Primary Synchronization Signal
SSS: Secondary Synchronization Signal
A basic rule of thumb is that the neighboring cells should not have the same “_____” value
1) SSS
2) PSS
PSS
Physical Cell Identity (PCI) planning
PSS range from
1) 0-3
2) 0-8
3) 0-167
4) 0-503
0-3
(4 values)
4G Physical Cell Identity (PCI) planning
SSS range from
1) 0-3
2) 0-8
3) 0-167
4) 0-503
0-167
(168 values)
4G Physical Cell Identity (PCI) planning
PCI range from
1) 0-3
2) 0-8
3) 0-167
4) 0-503
0-503
(504 values)
the channels are scrambled using the PCI
T/F
T
every ___ PCI will have same location of PCFICH for 20MHz channels.
every ____ PCI will have same location of PCFICH for 10MHz channels.
1) 50th, 25th
2) 25th, 50th
50th, 25th
2 PCFICHs usually ______ (overlap/do not overlap) each other completely. T/F
do not overlap
5G Physical Cell Identity (PCI) planning
SSS range from
1) 0-3
2) 0-335
3) 0-167
4) 0-503
0-335
(336 values)
5G Physical Cell Identity (PCI) planning
PSS range from
1) 0-3
2) 0-335
3) 0-167
4) 0-503
0-3
(4 values)
5G Physical Cell Identity (PCI) planning
PCI range from
1) 0-3
2) 0-335
3) 0-563
4) 0-1007
0-1007
(1008 values)
5G NR has _______ of the PCI’s compared to LTE 4G
1) double
2) triple
double
To identify an eNodeB globally use the code
1) CGI
2) MCC
3) MNC
4) TAC
5) CID
CGI: Cell Global Identity
code given by ITU for a country
1) CGI
2) MCC
3) MNC
4) TAC
5) CID
MCC: Mobile Country Code
3-digt code
404 and 405 for india
two or three-digit number used to identify a home Public Land Mobile Network (PLMN)
1) CGI
2) MCC
3) MNC
4) TAC
5) CID
MNC: Mobile Network Code
Allocated by National Regulator
72 for BSNL Kerala
75 for BSNL Bihar etc
Home Network Identity (HNI) is derived from codes (select two)
1) CGI
2) MCC
3) MNC
4) TAC
5) CID
2) MCC: Mobile Country Code
3) MNC: Mobile Network Code
PLMN ID=MCC+MNC
The term used in LTE corresponding to LAC in GSM/UMTS
1) CGI
2) MCC
3) MNC
4) TAC
5) CID
TAC: Tracking Area Code
16-bit code
PLMN ID+TAC P-GW
sector ID for omni-directional antennas
1) 0
2) 1
3) 2
0
CGI, ECGI, NCGI stands for _______ refers to which generations
CGI: Cell Global Identification (2G/3G)
ECGI: E-UTRAN CGI (4G)
NCGI: NR CGI (5G)
LAI consists of _____
1) PLMN & LAI
2) PLMN & LAC
3) PLMN & MNC
4) PLMN & TAC
PLMN & TAC
ECGI for LTE stands for
E-UTRAN cell Global Identifier
(28bits length)
ECGI=MCC +MNC + Cell ld
Cell ld: EnodeB ld+ Cell Identity
