UMTS ... is 3G technology and concepts. It introduced a new radio access network called UTRAN and a new air interface called WCDMA. The core network was initially based on GSM/GPRS but was expanded with new nodes. UMTS defined four quality of service classes and new protocols were introduced for the user plane and control plane in UTRAN and between network elements. Key concepts included serving and drift RNCs for soft handover, and SRNS relocation for changing the serving RNC.
3. 3GPP Rel.’99 network architecture
Core network (GSM/GPRS-
based)
Radio access network
UTRAN
UEUE
Iu CS
Iur
Iub
Uu
Gn
Iu PS
database
IP
Backbone
Internet
PSTN
BSBS
BSBS
RNCRNC
RNCRNC
MSCMSC
VLRVLR
SGSNSGSN
GMSCGMSC
HLRHLR
AuCAuC
EIREIR
GGSNGGSN
Iub
4. 3GPP Rel.’99 network architecture
Radio access network
UTRAN
UEUE Iur
Iub
Uu
BSBS
BSBS
RNCRNC
RNCRNC
Iub
2G => 3G MS => UE
(User Equipment), often
also called (user) terminal
New air (radio) interface
based on WCDMA access
technology
New RAN architecture
(Iur interface is available
for soft handover,
BSC => RNC)
5. 3GPP Rel.’99 network architecture
Core network (GSM/GPRS-
based)
Iu CS
Gn
Iu PS
IP
Backbone
Internet
PSTN
MSCMSC
VLRVLR
SGSNSGSN
GMSCGMSC
HLRHLR
AuCAuC
EIREIR
GGSNGGSN
Changes in the core
network:
MSC is upgraded to
3G MSC
SGSN is upgraded to
3G SGSN
GMSC and GGSN
remain the same
AuC is upgraded
(more security
features in 3G)
6. 3GPP Rel.4 network architecture
Circuit Switched (CS)
core network
UTRAN
(UMTS Terrestrial
Radio Access
Network)
PSTN
MSC
Server
MSC
Server
New option in Rel.4:
GERAN
(GSM and EDGE
Radio Access
Network)
PS core as in Rel.’99
GMSC
Server
GMSC
Server
SGWSGW
MGWMGW
SGWSGW
MGWMGW
7. 3GPP Rel.4 network architecture
Circuit Switched (CS)
core network
PSTN
MSC
Server
MSC
Server
PS core as in Rel.’99
GMSC
Server
GMSC
Server
SGWSGW
MGWMGW
SGWSGW
MGWMGW
MSC Server takes care
of call control signalling
The user connections
are set up via MGW
(Media GateWay)
“Lower layer” protocol
conversion in SGW
(Signalling GateWay)
RANAP / ISUPRANAP / ISUP
SS7
MTP
SS7
MTP
IP
Sigtran
IP
Sigtran
8. 3GPP Rel.5 network architecture
CS core
PSTN
SGSNSGSN GGSNGGSN
MGWMGW
Internet
HSSHSS
IMS (IP
Multimedia
System)
IMS (IP
Multimedia
System)
PS core
UTRAN
(UMTS Terrestrial
Radio Access
Network)
GERAN
(GSM and EDGE
Radio Access
Network)
New core
network part:
9. 3GPP Rel.5 network architecture
CS core
PSTN
SGSNSGSN GGSNGGSN
Internet/otherIMS
HSSHSS
PS core
The IMS can establish
multimedia sessions
(using IP transport)
via PS core between
UE and Internet (or
another IMS)
Call/session control
using SIP (Session
Initiating Protocol)
Interworking with the
PSTN may be required
for some time ...
IMS (IP
Multimedia
System)
IMS (IP
Multimedia
System)
MGWMGW
10. UMTS bearer service architecture
TE MT UTRAN CN Iu
edge node
TECN
gateway
End-to-end service
UMTS bearer service
Radio access bearer service CN b.s.
Local b.s. Ext. b.s.
Radio b.s. Iu b.s. Backbone
Radio Access BearerRadio Access BearerRadio BearerRadio Bearer
UE Core network
11. What is a bearer?
Bearer: a bearer capability of defined capacity, delay
and bit error rate, etc. (as defined in 3GPP specs.)
Bearer is a flexible concept designating some kind of
”bit pipe”
• at a certain network level (see previous slide)
• between certain network entities
• with certain QoS attributes, capacity, and traffic
flow characteristics
Four UMTS QoS Classes
• conversational, streaming, interactive, background
12. UMTS QoS (service) classes
ConversationalConversational StreamingStreaming InteractiveInteractive BackgroundBackground
low delay
low delay
variation
video
telephony/
conferencing
speech
video streaming
audio streaming
low round-trip
delay
www
applications
delay is not
critical
store-and-
forward
applications
(e-mail, SMS)
file transfer
reasonably low
delay
basic
applications
basic QoS requirements
13. Four UMTS QoS (service) classes
ConversationalConversational StreamingStreaming InteractiveInteractive BackgroundBackground
• speech (using AMR = Adaptive Multi-Rate speech coding)
• video telephony / conferencing:
ITU-T Rec. H.324 (over circuit switched connections)
ITU-T Rec. H.323 or IETF SIP (over packet switched
connections)
• low delay (< 400 ms) and low delay variation
• BER requirements not so stringent
• in the radio network => real-time (RT) connections
14. Adaptive Multi-Rate coding
kbit/s
12.2 (= GSM EFR)
10.2
7.95
7.40 (= US TDMA)
6.70 (= PDC EFR)
5.90
5.15
4.75
Adaptive
<=>
During the call,
the AMR bit rate
can be changed,
using the values
at the right
EFR = Enhanced
Full RateCodec negotiation
between transcoders
<=>
15. Transcoding
UEUE MSCMSC GMSCGMSC User BUser B
TCTC
Transcoder (AMR/PCM) should be located as far as
possible to the right (transmission capacity savings)
TCTC
Transcoding should be avoided altogether (better signal
quality)
TFO = Tandem Free Operation (2G)
TrFO = Transcoder Free Operation (3G)
(possible only if same coding is used at both
ends of connection)
(e.g. in PSTN)
16. Four UMTS QoS (service) classes
ConversationalConversational StreamingStreaming InteractiveInteractive BackgroundBackground
• video streaming
• audio streaming
• reasonably low delay and delay variation
• BER requirements quite stringent
• traffic management important (variable bit rate)
• in the radio network => real-time (RT) connections
UEUE SourceSource
video or audio information is buffered in the UE,
large delay => buffer is running out of content!
Buffer
17. Four UMTS QoS (service) classes
ConversationalConversational StreamingStreaming InteractiveInteractive BackgroundBackground
• web browsing
• interactive games
• location-based services (LCS)
• low round-trip delay (< seconds)
• delay variation is not important
• BER requirements stringent
• in the radio network => non-real-time (NRT) connections
18. Four UMTS QoS (service) classes
ConversationalConversational StreamingStreaming InteractiveInteractive BackgroundBackground
• SMS (Short Message Service) and other more advanced
messaging services (EMS, MMS)
• e-mail notification, e-mail download
• file transfer
• delay / delay variation is not an important issue
• BER requirements stringent
• in the radio network => non-real-time (NRT) connections
19. UMTS protocols
Different protocol stacks for user and control plane
User plane (for transport of user data):
Circuit switched domain: data within ”bit pipes”
Packet switched domain: protocols for implementing
various QoS or traffic engineering mechanisms
Control plane (for signalling):
Circuit switched domain: SS7 based (in core network)
Packet switched domain: IP based (in core network)
Radio access network: UTRAN protocols
20. Data streamsData streams
RLCRLC
MACMAC
Phys.Phys.
UE UTRAN 3G MSC GMSC
Uu Iu Gn
User plane protocol stacks (CS domain)
RLCRLC
MACMAC
Phys.Phys.
WCDMAWCDMA
TDMTDM
Frame Protocol (FP)Frame Protocol (FP)
AAL2AAL2
ATMATM
Phys.Phys.
AAL2AAL2
ATMATM
Phys.Phys.
TDMTDM
22. Uu (air, radio) interface protocols
PHYPHY
MACMAC
RLCRLC
RRCRRC
Signalling
radio bearers
(User plane)
radio bearers
e.g. MM, CC, SM
transparent to UTRAN
Logical channels
Transport channels
PDCPPDCP
L3
L2
L1
23. Main tasks of Uu interface protocols
MAC (Medium Access Control):
• Mapping between logical and transport channels
• Segmentation of data into transport blocks
RLC (Radio Link Control):
• Segmentation and reassembly
• Link control (flow & error control)
• RLC is often a transparent layer
PDCP (Packet Data Convergence Protocol):
• IP packet header compression (user plane only)
24. Main tasks of RRC protocol
Over the air interface, Radio Resource Control (RRC)
messages carry all the relevant information required for
setting up a Signalling Radio Bearer (during the lifetime
of the RRC Connection) and setting up, modifying, and
releasing Radio Bearers between UE and UTRAN (all
being part of the RRC Connection).
RRC also participates in the co-ordination of other Radio
Resource Management (RRM) operations, such as
measurements and handovers.
In addition, RRC messages may carry in their payload
higher layer signalling information (MM, CC or SM) that
is not related to the air interface or UTRAN.
25. General protocol model for UTRAN
Radio
Network
Layer
Transport
Network
Layer
Control Plane User Plane
Transport Netw.
Control Plane
Application
Protocol
Application
Protocol
Data
Stream(s)
Data
Stream(s)
Signalling
Bearer(s)
Signalling
Bearer(s)
ProtocolProtocol
Data
Bearer(s)
Data
Bearer(s)
Transport Netw.
User Plane
Transport Netw.
User Plane
Signalling
Bearer(s)
Signalling
Bearer(s)
Physical LayerPhysical Layer
26. Control Plane (Iub, Iur and Iu interfaces)
Radio Network Layer: application protocols (NBAP,
RNSAP and RANAP) are used for the actual signalling
between base stations, RNC and core network.
Transport Network Layer: signalling bearer for the
transport of application protocol messages is set up by
O&M actions (i.e. on a permanent basis).
Transport Network Control Plane
A signalling bearer (set up by O&M actions) carries a
protocol which is used only for the task of setting up
data bearers (e.g. AAL 2 connections).
27. User Plane (Iub, Iur and Iu interfaces)
The User Plane is employed for transport of
• user information (speech, video, IP packets ...)
• RRC signalling messages (Iub, Iur)
• higher-layer protocol information at Iu interface
(if not carried by RANAP).
User plane data is carried by data bearers which use
AAL 5 in case of Iu PS and AAL 2 in all other cases.
User data streams are packed in frame protocols (FP)
which are used for framing, error & flow control, and
carrying of parallel data flows that form the user data
signal (e.g. AMR encoded speech).
28. Protocol structure at Iub interface
Radio
Network
Layer
Transport
Network
Layer
Control Plane
Transport Netw.
Control Plane
NBAPNBAP
Transport Netw.
User Plane
Transport Netw.
User Plane
Q.2630.1Q.2630.1
Convergence
Protocols
Convergence
Protocols
AAL 5AAL 5
Conv. Pr.Conv. Pr.
AAL 5AAL 5 AAL 2AAL 2
ATMATM
Physical LayerPhysical Layer
RRCRRC DataData
RLCRLC
MACMAC
Frame ProtocolFrame Protocol
29. Control Plane
Transport Netw.
Control Plane
RNSAPRNSAP
Transport Netw.
User Plane
Transport Netw.
User Plane
Q.2630.1Q.2630.1
Convergence
Protocols
Convergence
Protocols
AAL 5AAL 5
Conv. Pr.Conv. Pr.
AAL 5AAL 5 AAL 2AAL 2
ATMATM
Physical LayerPhysical Layer
Protocol structure at Iur interface
Radio
Network
Layer
Transport
Network
Layer
RRCRRC DataData
RLCRLC
MACMAC
Frame ProtocolFrame Protocol
30. Radio
Network
Layer
Transport
Network
Layer
Control Plane User Plane
Transport Netw.
Control Plane
RANAPRANAP
Transport Netw.
User Plane
Transport Netw.
User Plane
Q.2630.1Q.2630.1
Convergence
Protocols
Convergence
Protocols
AAL 5AAL 5
Conv. Pr.Conv. Pr.
AAL 5AAL 5
CS ChannelCS Channel
Iu UPIu UP
AAL 2AAL 2
ATMATM
Physical LayerPhysical Layer
Protocol structure at Iu CS interface
31. Radio
Network
Layer
Transport
Network
Layer
Control Plane User Plane
Transport Netw.
Control Plane
RANAPRANAP
Transport Netw.
User Plane
Convergence
Protocols
Convergence
Protocols
AAL 5AAL 5
IP ApplicationIP Application
Protocol structure at Iu PS interface
GTPGTP
UDPUDP
IPIP
AAL 5AAL 5
ATMATM
Physical LayerPhysical Layer
Iu UPIu UP
32. Application protocols in UTRAN
Iub interface (between RNC and base station)
NBAP (Node B Application Part)
Iur interface (between Serving RNC and Drift RNC)
RNSAP (Radio Network Subsystem Application Part)
- Link management for inter-RNC soft handover
Iu interface (between RNC and core network)
RANAP (Radio Access Network Application Part)
- Radio Access Bearer (RAB) management
- SRNS Relocation
- Transfer of higher-level signalling messages
33. Serving RNC and Drift RNC in UTRAN
Core
network
Iu
Iur
Iub
Iub
DRNC
SRNC
UEUE
BSBS
BSBS
RNCRNC
RNCRNC
Concept needed for:
Soft handover between base stations belonging to different RNCs
34. Serving RNS (SRNS) Relocation
RNS = Radio Network Sub-system =
RNC + all base stations controlled by this RNC
SRNS Relocation means that the Serving RNC
functionality is transferred from one RNC (the “old”
SRNC) to another (the “new” SRNC, previously a
DRNC) without changing the radio resources and
without interrupting the user data flow.
RANAP provides the signalling facilities over the
two Iu interfaces involved (Iu interfaces to “old”
and “new” SNRC) for performing SRNC Relocation
in a co-ordinated manner.
37. Micro- / macrodiversity combining
Iu
Iur
Iub
Iub
DRNC
SRNC
UEUE
BSBS
BSBS
RNCRNC
RNCRNC
Macrodiversity
combining point
in SRNC
Core
network
Rake
receiver
Multipath
propagation
Microdiversity combining point in base station
(uplink)
38. Micro- / macrodiversity combining
Microdiversity combining: multipath signal
components are processed in Rake “fingers” and
combined (= summed) using MRC
(MRC = Maximum Ratio Combining)
Macrodiversity combining: the same bit sequences
(with different bit error positions) are combined at
the SRNC (usually: selection combining).
Hard handover: slow (a lot of signalling)
Soft handover: fast selection in SRNC
(uplink)
39. Radio Access Bearer (RAB) establishment
RAB assignment request
RAB assignment complete
RAB is configured to be used
over existing Radio Link(s)
(RANAP signaling)
UE BS RNC
(RRC signaling)
Core network
40. Signalling between UE and core network
UEUE BSBS RNCRNC MSC or
SGSN
MSC or
SGSN
RRC RANAP
NAS signalling messages (NAS = Non Access Stratum =
“not related to UTRAN”) are sent transparently through
UTRAN in the payload of RRC/RANAP protocol messages
41. Security in UMTS
GSM UMTS
SIM authentication
(PIN code)
SIM authentication
(PIN code)
User authenticationUser authentication
Ciphering (air interface)Ciphering (air interface)
Signalling data integritySignalling data integrity
IP security (e.g. IPSEC)IP security (e.g. IPSEC)
User authenticationUser authentication
Network authenticationNetwork authentication
USIM authentication
(PIN code)
USIM authentication
(PIN code)
Ciphering (air interface)Ciphering (air interface)
KASUMI algorithm (known)
UMTS: larger key lengths
than in GSM
42. Security in digital networks: terminology
Authentication:
SIM authentication (PIN code)
user authentication (GSM, UMTS, DECT, TETRA)
network authentication (UMTS, TETRA)
Integrity:
signalling data integrity (UMTS)
Confidentiality (≈ privacy):
ciphering of signals over radio interface
hiding of user identifiers over radio interface
end-to-end encryption (offered by service provider)
43. Authentication
Authentication: Procedure of verifying the authenticity
of an entity (user, terminal, network, network element).
In other words, is the entity the one it claims to be?
SIM authentication is local (network is not involved)
In GSM, only user is authenticated
In UMTS, both user and network are authenticated
User/network is authenticated at the beginning of
each user-network transaction (e.g. location updating
or connection set-up) and always before ciphering
starts.
See Security in GSM
for more details
44. Integrity
Data integrity: The property that data has not been
altered in an unauthorised manner.
“Man-in-the-middle” security attack, e.g. false BS
Data integrity checking is not done in GSM
In UMTS, signalling messages are appended with a
32 bit security field (MAC-I) at the terminal or RNC
before transmission and checked at the receiving end
In UMTS, also volume of user data (not the user data
itself) is integrity protected
45. Signalling integrity protection in UMTS
Signalling messageSignalling message
Algorithm f 9
MAC-IMAC-I
Integrity Key (IK)
and other
keys/parameters
UEUE RNCRNC
MAC-I generation MAC-I checking
MAC-I generationMAC-I checking
Both in
terminal
and RNC
46. Confidentiality
Confidentiality: The property that information is not
made available to unauthorised individuals, entities or
processes.
Example 1: Ciphering (encryption) over the air interface
Example 2: Preventing unencrypted transmission of
user ID information such as IMSI number over the air
interface
=> Temporary Mobile Subscriber Identity (TMSI) is
generated (at the end of each MM or CM transaction)
and is used at the beginning of the next transaction
instead of IMSI.
47. Example 1: ciphering (encryption)
BSBS
MSMS
UEUE
BTSBTS BSCBSC
RNCRNC
SGSNSGSN
Core NetworkCore Network
Air interface
GPRS
UMTS
MSMS BTSBTS BSCBSC Core NetworkCore Network
GSM
Both CS and PS information
Signalling integrity protection
48. Network domain security
Circuit switched network => quite good
IP-based network (Internet) => rather poor at present
(security mechanisms are developed by IETF, 3GPP...)
Some security threats in IP-based network:
Sniffing (electronic eavesdropping)
Spoofing, session hijacking
Denial of service (DoS), ”spamming”
Confidentiality
Integrity
50. RLCRLC RLCRLC
Logical / Transport / Physical channels
MACMAC
FPFP
PhyPhy FPFP
UE Base station RNC
AAL 2AAL 2
MACMAC
AAL 2AAL 2
PhyPhy
Logical channels
Physical channels
Transport channels
: :
WCDMA
::
51. Logical / Transport channels
CCCHCCCH DCCHDCCH
PCHPCH DCHDCHDSCHDSCHFACHFACHBCHBCHDCHDCHCPCHCPCHRACHRACH
DCCHDCCHCTCHCTCHCCCHCCCHBCCHBCCHPCCHPCCH
Uplink Downlink
DTCHDTCH DTCHDTCH
Logical channels
Transport channels
52. Transport / Physical channels
PCHPCH DCHDCHDSCHDSCHFACHFACH BCHBCH
DCHDCH
CPCHCPCHRACHRACH
PRACHPRACH PCPCHPCPCH SCCPCHSCCPCH PCCPCHPCCPCH DPDCHDPDCH
DPCCHDPCCH
SCHSCHCPICHCPICH
AICHAICH
PICHPICH
CSICHCSICH
Physical channels
Transport channels
DPCHDPCH
CD/CA-
ICH
CD/CA-
ICH
Uplink Downlink
PDSCHPDSCH
53. Physical channels in WCDMA
Bit sequences from different physical channels are
multiplied with a channelization code (spreading)
multiplied with a scrambling code (scrambling)
multiplexed in code domain
modulated using QPSK.
Downlink channels: conventional QPSK modulation
DPCH = Dedicated physical channel
Uplink channels: Dual-channel QPSK moduation
DPDCH = Dedicated physical data
channel
DPCCH = Dedicated physical control channel
54. DPCH structure in downlink
TFCITFCI DataData TPCTPC DataData
10 ms radio frame
0 1 2 14
2560 chips
PilotPilot
QPSK modulation,
time multiplexed data and control information:
(DPCH = Dedicated Physical Channel)
57. Spreading in WCDMA
Chip rate = SF x channel bit rateChip rate = SF x channel bit rate
Chip rate after spreading = 3.84 Mchips/sChip rate after spreading = 3.84 Mchips/s
Uplink: DPCCH SF = 256, DPDCH SF = 4 - 256Uplink: DPCCH SF = 256, DPDCH SF = 4 - 256
Downlink: DPCH SF = 4 - 256 (512)Downlink: DPCH SF = 4 - 256 (512)
Spreading factor (SF) is important in WCDMA
One bit consists
of 256 chips
One bit consists
of 4 chips
58. Uplink DPDCH bit rates
256
128
64
32
16
8
4
SF Channel bit rate
(kb/s)
User data rate
(kb/s)
15
30
60
120
240
480
approx. 7.5
approx. 15
approx. 30
approx. 60
approx. 120
approx. 240
960 approx. 480
59. Downlink DPDCH bit rates
256
128
64
32
16
8
4
SF Channel bit rate
(kb/s)
User data rate
(kb/s)
15
30
60
120
240
480
approx. 1-3
approx. 6-12
approx. 20-24
approx. 45
approx. 105
approx. 215
960 approx. 456
512
1920 approx. 936
60. User data rate vs. channel bit rate
Channel bit rate (kb/s)Channel bit rate (kb/s)
User data rate (kb/s)User data rate (kb/s)
Channel codingChannel coding
InterleavingInterleaving
Bit rate matchingBit rate matching
Interesting
for user
Interesting
for user
Important
for system
Important
for system
62. New service concept
End userEnd user End userEnd user
Carrier providerCarrier provider
Service providerService provider Service providerService provider
Content providerContent provider Content providerContent provider
all want to
make profit
63. OSA is being standardised, so that services provided
by different service/content providers can be created
and seamlessly integrated into the 3G network (this is
the meaning of “open” architecture)
OSA (Open Services Architecture/Access)
3G network
API API API
Service Creation Environment (SCE)
API =
Application
Programming
Interface
(Standardised)
OSA means in practice:
64. CAMEL (Customised Applications for Mobile network
Enhanced Logic) is a set of “IN” type functions and
procedures that make operator-specific IN services
available to subscribers who roam outside their home
network.
CAMEL = IN technology + global mobility
CAMEL Service Environment (CSE) is a logical entity in
the subscriber’s home network which processes IN
related procedures
CSE ≈ SCP in home network
CAMEL (2G & 3G)
65. Circuit switched call-related IN procedures
CAMEL Phase 1
1. Call control proceeds up to MSC
SSPSSP
MSCMSC
SCP in home
network (CSE)
SCP in home
network (CSE)
1.
2.
3.
4.
5.
2. Trigger activated in basic call state model at SSP
3. SSP requests information from CSE
4. CSE provides information
5. Call control continues
Typical
triggers:
Calling number
Called number
Cell ID
Protocol: CAP instead of MAP
66. CAMEL Phase 2
Non-call-related procedures possible
1. Call control proceeds as normal
2. Call control is interrupted
3. Call control resumes
Typical
application:
In prepaid service:
announcement
”your prepaid
account is
approaching zero”
(e.g. for announcement)
IN functionality is extended to include packet switched
sessions...
CAMEL Phase 3
67. Virtual Home Environment (VHE)
Same subscriber profile & charging/numbering information
can be utilised in any UMTS network
Home PLMN Visited PLMN
UEUE
Certain subscriber
profile
Same subscriber
profile
68. Supporting technologies and services
PositioningPositioning
SMSSMS
USSDUSSD
MMSMMSLCSLCS
SATSAT USATUSAT
MExEMExE
WAPWAP
Location
UE
Transport
&
Contenti-Modei-Mode
- many are already possible in 2G
- will (perhaps) be extensively used in 3G
69. Location (based) services (LCS)
- may or may not use UE positioning techniques
- general LCS architecture in UMTS:
UEUE
PSTN
Internet
BSBS
LMULMU
RNC &
SMLC
RNC &
SMLC
MSCMSC
GMLCGMLC
SGSNSGSN GGSNGGSN
HLR/AuC/EIRHLR/AuC/EIR
GMSCGMSC
LCS External
Client
70. Location (based) services (cont.)
GMLC = Gateway Mobile Location Center
receives service requests from external LCS clients
(or UE) and manages the location information
SMLC = Serving Mobile Location Center
assists in positioning of the UE (e.g. performs
calculations based on measurement results), is
usually integrated with RNC
LCS client = typically any server requesting location
information (to be able to provide the relevant
location service to the user), may also be the UE
71. Positioning methods
BSBS
BSBS
BSBS
UEUE LMULMU
Cell ID based location information
- no expensive positioning solutions required
- inexpensive (and will
therefore be widely used)
E-OTD (2G), OTDOA (3G)
- differential delays measured
from which the position
is calculated (in SMLC)
Assisted GPS
- greatest precision, GPS receiver in UE
- network must “assist” in indoor environment
SMLCSMLC
72. SAT (= USAT in 3G)
SAT (SIM Application Toolkit) is a set of standardized
functions for communication between SIM and ME
SIM
ME
Applications (GSM 11.14):
• profile download (ME tells SIM what it can do)
• proactive SIM (display text from SIM to ME, send
short message, transfer info from ME to SIM,...)
• call control by SIM
• data download from network to SIM
Download (e.g. Java applets) from server in
network will be important in UMTS
Interaction between ME and SIM
73. MExE
Mobile Execution Environment (MExE) provides
standardized application execution environments for
UE, defined in classmarks:
MExE Classmark 1
MExE Classmark 2
MExE Classmark 3
UE is WAP compatible (i.e. contains
WAP browser)
UE can execute PersonalJava
applications (subset of J2SE)
UE is J2ME compatible Standard
Edition
Micro Edition:
see: www.mexeforum.org Evolution continues ...
74. SMS vs. USSD
SMS = Short Message Service
USSD = Unstructured Supplementary Services Data
SMS
• 160 ASCII characters (max)
• in all GSM terminals
• store-and-forward service
(=> delay)
• transport of messages
• SMS transaction always
initiated by terminal
USSD
• 182 ASCII characters (max)
• in all GSM terminals
• connection oriented
transactions (small delay)
• transport of technical data
• terminal or application in
network initiates session
very popular not much used (yet)
75. MMS
MMS = Multimedia Messaging System
Offers the possibility to send messages to/from MMS
capable handsets comprising a combination of
- text
- sounds
- images
- video
GPRS or 3G packet domain can be used for transport.
When combined with LCS information and IN (CAMEL)
features, interesting new services can be implemented.
76. WAP (Wireless Application Protocol)
Transports WML (Wireless Markup Language)
information between terminal and WAP Gateway (using
its own set of protocols)
WAP
Gateway
WAP
Gateway
UEUE 2G/3G
networ
k
Internet
Server
Internet
Server
WAP
browser WML / HTML
translation
WMLWML
WAP protocolsWAP protocols
2G/3G transport2G/3G transport
WML is a subset of XML
e.g. WTP (similar functionality as HTTP)
SMS, USSD, GPRS, 3G packet transport ...
WML /
HTML / XML
content
77. Service interaction example
3G subscriber is hungry and asks for a list of nearby
located restaurants (from appropriate “Internet Server”).
Network scenario:
UEUE
2G/3G
networ
k
WAP
Gateway
WAP
Gateway
Internet
Server
Internet
Server
CAMEL
(CSE)
CAMEL
(CSE)
GMLCGMLC MExEMExE
See:
Kaaranen et al:
UMTS Networks
78. Example, Step 1
By use of his/her WAP browser in the UE, user contacts
(via WAP Gateway) the “Internet Server” containing
relevant information.
UEUE
2G/3G
networ
k
WAP
Gateway
WAP
Gateway
Internet
Server
Internet
Server
CAMEL
(CSE)
CAMEL
(CSE)
GMLCGMLC MExEMExE
WAP
browser
79. Example, Step 2
The 2G/3G network retrieves subscription information
(e.g. state of “prepaid” account) from the user’s CSE
(Camel Service Environment).
Charging
info
UEUE
2G/3G
networ
k
WAP
Gateway
WAP
Gateway
Internet
Server
Internet
Server
CAMEL
(CSE)
CAMEL
(CSE)
GMLCGMLC MExEMExE
80. Example, Step 3
“Internet Server” acts as a “LCS client” and requests the
2G/3G network to investigate where the user is located.
UEUE
2G/3G
networ
k
WAP
Gateway
WAP
Gateway
Internet
Server
Internet
Server
CAMEL
(CSE)
CAMEL
(CSE)
GMLCGMLC MExEMExE
Where is UE located?
81. Example, Step 4
The “MExE compatible Internet Server” prepares the
information according to the MExE capabilities of UE
(in this case MExE Classmark 1: WAP).
What can UE
display?
UEUE
2G/3G
networ
k
WAP
Gateway
WAP
Gateway
Internet
Server
Internet
Server
CAMEL
(CSE)
CAMEL
(CSE)
GMLCGMLC MExEMExE
?
?
82. Example, Step 5
Now the “local restaurants” information is downloaded to
the user and displayed in the appropriate form.
Restaurant 1
Restaurant 2
Restaurant 3
Restaurant 4
Menu on display:
UEUE
2G/3G
networ
k
WAP
Gateway
WAP
Gateway
Internet
Server
Internet
Server
CAMEL
(CSE)
CAMEL
(CSE)
GMLCGMLC MExEMExE
83. Further information on 3G systems and
services
Links: see slides
Books:
Kaaranen et al., UMTS Networks: Architecture, Mobility and
Services, Wiley, 2001, ISBN 0-471-48654-X
Korhonen, Introduction to 3G Mobile Communications, Artech
House, 2001, ISBN 1-58053-287-X
Web material:
e-learning course “Introduction to 3G” contains audio and
flash animations (you need loudspeakers; access to course
only within the HUT computer network)
http://130.233.158.46/eopetus/intro3g/start.htm
Required course material