Securiy features in Mobile networks Flashcards
The ___ controls the allocation of new Temporary Mobile Subscriber Identity
(TMSI) numbers and notifies them to the ____
1) VLR allots and notifies HLR
2) HLR allots and notifies VLR
VLR allots and notifies HLR
TMSI may be updated while
1) Call setup
2) On entry to a new LAI
3) On entry to a new VLR
4) all the above
all the above
GSM air interface ____frequency hopping
1) supports
2) does not support
supports
frequency hopping is employed to
1) optimize network performance
2) make secure interface
3) saving spectrum
frequency hopping is employed to optimize network performance by overcoming interference problems in busy areas, to increase call quality
and capacity.
SIM card contains
1) security related information (IMSI, Ki, PIN)
2) subscriber related information
3) the algorithms A3 and A8
4) all the above
SIM card contains security related information (IMSI, Ki, PIN), other subscriber related information and the algorithms A3 and A8
SIM card contains
1) IMSI
2) TMSI
3) MSISDN
IMSI
SIM card contains algorithms
1) A3 and A8
2) A3 and A5
3) A5 and A8
1) A3 and A8
MS contains algorithm
1) A3
2) A5
3) A8
A5
Vernam Cipher algorithm
Vernam Cipher algorithm
1) A3
2) A5
3) A8
A5 in MS
The _____channel of the base system broadcasts a code to tell the mobile
station which of the encryption algorithms is in use that particular base GSM installations
1) SCH channel
2) BCCH channel
3) TCH channel
BCCH channel
GSM voice privacy encryption process uses _____ algorithm
1) A3
2) A5
3) A8
A5
Vernam Cipher algorithm
The encryption code (cipher mask) continuously varies and is synchronized to the _______ at both the base and mobile stations
1) burst counter
2) hyper-frame counter
hyper-frame counter
______ cipher mask bits for each normal burst in the data stream that is synchronized with the hyper-frame counter
1) 64
2) 116
3) 128
4) 256
116
The cipher mask is added (modulo 2) to the transmit information and flag bits _______ differential encoding and modulation
1) before
2) after
before
The generation of the Kc is based on the ___ algorithms
1) A3
2) A5
3) A8
A8 Crypto Graphical alogorithms
This ciphering start procedure is initiated from the _____ by sending the message a cipher mode command the ___.
1) MSC / HLR, Kc
2) MSC / VLR, Kc
3) MSC / HLR, Ki
4) MSC / VLR, Ki
MSC / VLR, Kc
The ___ will be removed from the message by the BTS before sending it on to the MS
1) Ki
2) Kc
Kc
Kc is sent _____ on the air
1) during initialization
2) during authorization
3) never
never
In 5G, AKA stands for
Authentication Key Agreement
In most cases for Authentication Key Agreement(AKA), operators use ___________ algorithm
1) A3, A5, A8
2) Milenage/TUAK
Milenage/TUAK
In 5G, KDF stands for
Key Derivation Function
In 5G, UDM stands for
Unified Data Management
In 5G, ASF/AUSF stands for
Authentication Server Function
In 5G, PCF stands for
Policy Control Function
In 5G, SMF stands for
Session Management Function
Match identifier and name (AES, ZUC, Snow3G)
128NEA-1
128NEA-2
128NEA-3
128NEA-1 : Snow3G
128NEA-2 : AES
128NEA-3 : ZUC
Identifier in 5G similar to IMSI for 2G/3G/4G
1) SUPI
2) GUTI
3) SUCI
SUPI (Subscription Permanent Identifier)
Identifier in 4G/5G similar to TMSI in 2G/3G
1) SUPI
2) GUTI
3) SUCI
GUTI(Globally Unique Temporary Identifier)
“_________” attacks persist in today’s mobile networks including the 4G LTE/LTE-Adv
1) IMSI catching
2) TMSI catching
IMSI catching
concealed SUPI is known as
1) CUPI
2) SUCI
SUCI (Subscription Concealed Identifier )
___ security specifications do
not allow plain-text transmissions of the IMSI/SUPI over the radio interface
1) 3G onwards
2) 4G onwards
3) 5G
5G
SUPI is concealed using
1) ECEIS
2) ECIES
3) ESIEC
4) EICES
2) ECIES ( Elliptic
Curve Integrated Encryption Scheme)
Only the MSIN part of the SUPI gets concealed by the protection scheme while the home network identifier i.e. MCC/MNC gets transmitted in plain-text
a valid SUPI can be
1) IMSI
2) NAI (Network Access Identifier)
3) either 1 or 2
either 1 or 2
Home Network Identifier in SUCI represents
1) MCC+MNC for IMSI
2) domain name representation for NAI
3) either 1 or 2
either 1 or 2
(SUCI type 0: IMSI, 1: NAI, 2 to 7: spare value for future use)
choose correct item(s)
Home Network Public Key Identifier
1) key used for cyphering
2) key used for SUPI protection
3) key used for traffic encryption
4) public key provisioned by the HPLMN
2 and 4
key used for SUPI protection
public key provisioned by the HPLMN
In 5G, AMF stands for
Access and Mobility Management
In 5G, GUAMI stands for
Globally Unique AMF ID
4G GUTI to 5G GUTI Conversion to identify
1) MME ID
2) AMF
3) SUPI
4) SUCI
MME ID
5G GUTI to 4G GUTI Conversion to identify
1) MME ID
2) AMF
3) SUPI
4) SUCI
AMF
The SUPI value is provisioned in
1) USIM
2) UDM/UDR function in 5G Core
3) both
both
Only the ____ part of the SUPI gets concealed by the 5G protection scheme
1) MCC
2) MNC
3) MSIN
MSIN
Home network identifier can be
1) MCC+MNC
2) domain name
3) either 1 or 2
either 1 or 2 depending on SUPI type value
____ is provisioned in USIM
1) TMSI
2) routing indicator
routing indicator
AMF provides new 5G GUTI when receiving
1) initial registraion request
2) periodic registration update
3)network triggered Service Request message
4) all of the above
all of the above
_______ is the shortened form of the GUTI to enable more efficient radio signalling procedures e.g. during Paging and Service Request
1) TMSI
2) S-TMSI
3) AMF ID
S-TMSI
