18.11.2002Antti Siitonen, 2002
UMTS
Antti Siitonen
Development manager, MSc (EE)
› T-110.300 Telecommunications architectures
› Lectures on 14.11.2002
› Introduction to UMTS
28.11.2002Antti Siitonen, 2002
Contents1. Introduction to UMTS
1.1. Standards evolution
1.2. Radio interface in general
1.3. Network architecture
1.4. Mobile handset
2. Services in UMTS environment
2.1. Theoretical bitrates and Quality of Service
2.2. Service capabilities
2.3. Service concepts
3. UMTS protocols
3.1. Protocol architectures in UMTS overview
3.2. Signalling
38.11.2002Antti Siitonen, 2002
Worldwide Telecommunications Growthmillions of customers
0
200
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1000
1200
1400
1600
1800
1996 1998 2000 2002 2004 2006 2008 2010
Fixed Mobile Internet Mobile Internetsource ETSI GMM report
48.11.2002Antti Siitonen, 2002
Picture: Nokia
UMTS
› Universal Mobile Telecommunications System
› UMTS = European variation of the WCDMA technology
› FDD and TDD bands
› New licences
› ”GSM combatible”
› What is new?
› Wideband data access and multimedia support
› Open service creation environment
› Videophone
58.11.2002Antti Siitonen, 2002
3G Standards
Variant Radio access Switching 2G Basis3G (US) WCDMA,
EDGE,CDMA2000
IS-41 IS-95,GSM1900,
TDMA3G (Europe) WCDMA, GSM,
EDGEAdvanced GSMNSS andpacket core
GSM 900/1800
3G (Japan) WCDMA Advanced GSMNSS andpacket core
PDC
UMTS
• UMTS standardization is done in 3GPP = 3rd Generation Partnership Project• ETSI = European Telecommunication Standard Institute / Europe• ARIB = Association of Radio Industries and Business / Japan• CWTS = China Wireless Telecommunication Standard Group / China• T1 = Standardisation Committee T1 - Telecommunications /US• TTC = Telecommunications Technology Committee /Japan• TTA = Telecommunication Technology Association /Korea
68.11.2002Antti Siitonen, 2002
3GPP Standards
2000 2003Q2
2001 2002Q2 Q1Q3 Q2 Q3Q4 Q4 Q1Q1 Q2 Q3 Q4Q4 Q3 Q1
3GPP Release 4 3GPP Release 5
3GPP Release 3(Release 1999)
Commercial servicesR3
Commercial servicesR4
Commercial servicesR5
78.11.2002Antti Siitonen, 2002
UMTS releases› Release 3 (Officially named Release 1999)
› UMTS expansion + EDGE
› quick start = faster GPRS, faster Circuit Switched Data
› MultiMediaMessaging (For GPRS also), Adaptive Multirate …
› New radio network for UMTS
› Release 4
› New network architecture: MSC server
› Location based services (PS), VHE, Camel 3, MAP over IP
› Release 5 (and Release 6)
› OSA, MediaGateway, GSN server
› IPv6 mandatory, IPv4 optional
› SIP signalling and VoIP
› Interfaces to other networks (WLAN ….)
88.11.2002Antti Siitonen, 2002
What is new with UMTS radio?
›In shot: everything
› Wideband CDMA - 2 Mbit/s channel bitrate» Soft handover
» Cell breathing
› Both FDD and TDD modes» Frequency Division Duplex
» Time Division Duplex
› New frequencies 2100 MHz = 2,1 GHz
› Later other frequency bands (900, 1800, 2600...)
› Cell planning is changed from frequency planning into capacityplanning
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WCDMA - cell breathing 1
64 kbit/s64 kbit/s 64 kbit/s
64 kbit/s64 kbit/s64 kbit/s
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WCDMA- cell breathing 2More load...
512 kbit/s
64 kbit/s64 kbit/s
64 kbit/s
64 kbit/s 64 kbit/s
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WCDMA- cell breathing 3Serving 2 Mbit user
2 Mbit/s
64 kbit/s
64 kbit/s
64 kbit/s
64 kbit/s
64 kbit/s
128.11.2002Antti Siitonen, 2002
WCDMA- cell breathing 4Several 2 Mbit users?
2 Mbit/s2 Mbit/s
2 Mbit/s
2 Mbit/s
138.11.2002Antti Siitonen, 2002
WCDMA frequencies (ITU)
1850 1900 1950 2000 2050 2100 2150 2200 2250 MHz
1850 1900 1950 2000 2050 2100 2150 2200 2250 MHz
NorthAmerica
MSS Reserve
Europe UMTSGSM 1800 DECT MSS
1880
1980
JapanKorea
MSSIMT 2000 MSSIMT 2000
2160
1893 1919
ITU Allocations
1885
IMT 2000
2010 2110 2170
China MSSIMT 2000IMT 2000
IMT 2000
MSSUMTS
MSS
1990
B BMSS
2025 22001900
MSS MSS
PCS
MSS =Mobile Satellite
Services
TDD
FDD
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WCDMA Frequency use
› 2 times more effective than GSM
› 1 WCDMA channel = 28 GSM channels
WCDMA 5MHz
.....
f
GSM 0,2 MHz
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UMTS Network release 99- Based mainly on GSM+GPRS
BSC
SS7
HLR VAS
GSMInternet
LAN
GPRS
PSTN
3G MSC
SGSN GGSN
RNC
UTRA
MS
UE
BTS
BS
Circuit Switched Domain
Packet Switched Domain
Camel, WAP, MExE, USAT
RNC
UTRA
BS
168.11.2002Antti Siitonen, 2002
UMTS Network release 4
BSC
SS7
GSMInternet
LAN
GPRS
PSTN
MSC Server
SGSN GGSN
RNC
UTRA
MS
UE
BTS
BS
Circuit Switched Domain
Packet Switched Domain
Media Gateway
Media Gateway
HSS
Switching
Control
HSS = Home Subscriber Server
VAS Camel, WAP, MExE, USAT
178.11.2002Antti Siitonen, 2002
Core network release 5 (6)
BSC
SS7
GSM Internet
MGW
RNC
UMTS
MS
UE
BS
BTS
IP/ATM
IP/ATM
HSS
HSS = Home Subscriber ServerCPS = Call Processing Server
VAS Camel, WAP, MExE, USAT
Core Network Packet Switched Domain
SGSN GGSN
IP/ATM
IMS
IMS = IP Multimedia SubsystemMGW+HSS+CPSSIP-signalling
PSTN
IP RAN
CPS
188.11.2002Antti Siitonen, 2002
Bearer architecture in UMTS
TE MT UTRAN CN Iu edge CN Gateway
End-to-end Service
TE = Terminal Equipment, MT = Mobile Termination, UTRAN = UMTS Radio Network, CN = Core Network
Local Bearer Service UMTS Bearer Service
External Bearer Service
Radio Access Bearer Service CN Bearer Service
Radio Bearer Service IU Bearer Service Backbone
Bearer Service
Backbone Phys. Bearer Service
Physical Bearer Service
UTRA Bearer Service
198.11.2002Antti Siitonen, 2002
UMTS Terminal, User Equipment (UE)
› Mandatory functions:
› Interface to USIM = Universal Subscriber Identity Module
› Service provider and network registration and deregistration
› Location update
› Originating and receiving connection orinented and connectionless services
› An unalternable equipment identification (IMEI)
› Basic identification of the terminal capabilities
› Emergency calls without USIM
› Authentication and ciphering algorithm support
› Optional, but important
› API, Service related information download, Virtual Home Environment maintenance interface, Secondary IC-card slot
208.11.2002Antti Siitonen, 2002
Terminal Complexity ComparisonMIPS
0
10
20
30
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50
60
70
80
90
Speech 8 kbit/s 144 kbit/s
GSM/EDGEWCDMA
Source: SMG2 evaluion documents by Nokia, Ericsson and Siemens
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Services in UMTS Environment
Content Provider Content Provider Content Provider
Service Provider Service Provider Service Provider
Carrier Provider Carrier Provider
End User End User
CommunicationServices
InfoServices
Games
End User
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Theoretical bitrates
› Theoretical bitrates seem to remain theory
› Specified rates are:
› In commercial deployments maximum bit rates are expected to be 384 kbit/s and basic service bit rate 64 kbit/s
› Indoor coverage for UMTS?
› One issue is also the availability of high speed terminals
Circuit Switched bitrate (kbit/s)
Packet Switched bitrate (kbit/s)
Coverage Type
144 kbit/s 144 kbit/s peak rate Basic coverage,rural/suburban,fast moving vehicles, outdoor
384 kbit/s 384 kbit/s peak rate Extended Coverage, urban,moving vehicles, outdoor
2 Mbit/s 2 Mbit/s peak rate Hot Spot areas, urban, centre,walking speeds, indoor
238.11.2002Antti Siitonen, 2002
Quality of Service
› Radio capacity optimisation
› Core Network and UTRAN independent from each other and surrounding networks
› Transport Network optimisation
› QoS classes:
› Conversational class: minimum fixed delay, no buffering, symmetric traffic, guaranteed bit rate = Real Time Traffic
› Streaming class: minimum variable delay, buffering allowed, asymmetric traffic, guaranteed bit rate = Near Real Time Traffic
› Interactive class: moderate variable delay, buffering allowed, asymmetric traffic, no guaranteed bit rate = Not Real Time Traffic
› Background class: big variable delay, buffering allowed, asymmetric traffic, no guaranteed bit rate = Data synchronisation
248.11.2002Antti Siitonen, 2002
Quality of Service (cont.)› QoS parameters in UMTS:
› Maximum bit rate (kbit/s)
› Guaranteed bit rate (Kbit/s)
› Allowed transfer delay (ms)
› Is QoS class negotiable?UE UTRAN CN
UMTS End-to-end Service
RAB = Radio Access Bearer, RRM = Radio Resource Management
UMTS Bearer Service: Request for UMTS QoS Class
RAB Assignment Request
RRM:- Admission Control
QoS NegotiationRadio Bearer and Radio Link establishment
RAB Assignment Response
UMTS Bearer Service with Negotiated QoS
258.11.2002Antti Siitonen, 2002
Quality of Service (cont.)
› Challenges:
› First typical use cases will be in hybrid networks (UMTS/GPRS/GSM), How is this taken into account?
› How much can content compression and background synchronisation solve user needs?
Conversational Streaming Interactive BackgroundMax. Bitrate (kbit/s)
< 2048 < 2048 < 2048 < 2048
GuaranteedBit rate(kbit/s)
< 2048 < 2048 N/A N/A
Symmetry Symmetric Asymmetric Asymmetric AsymmetricTransferdelay (ms)
100-250 > 250 N/A N/A
268.11.2002Antti Siitonen, 2002
Service capabilities
› Principle: Connections are separated from service maintaining
› Network components called service capabilities = service platforms
› Initially identified service capabilities (Release 99)
› WAP Server / WAP Gateway - Mobile browser capabilities
› Positioning servers - UE position information, Location Based Services
› Mobile Station Application Execution Environment - Provides information to other services about UE information handling capabilities
› UMTS SIM Application Toolkit (USAT) - SIM card handling tools
› Customised Applications for Mobile network Enhanced Logic (CAMEL)- Service interconnection point (Service control, implementation and provisioning)
278.11.2002Antti Siitonen, 2002
Service capabilities (cont.)
› In Release 4 there are new possibilities for service creation
› OSA = Open Service Architecture
› Common centralized point for Service Creation
= Service Creation Environment (SCE)
› All capabilities implemented are accessible via APIs
› Practically CAMEL is required for effective service creation
› Possibility to make the services roam between networks
› Challenge:
› Will the operators open the networks for open service creation?
288.11.2002Antti Siitonen, 2002
Location Communication Services
› There are different methods to provide UE position information to services or users
› Cell ID based positioning
› Round-Trip Time (RTT) based positioning
› Timing Advance, Received Signal Strength (TA/Rx)
› Time-of-Arrival (TOA) positioning
› Time Difference of Arrival (TDOA) positioning
› Enhanced Observed Time difference (E-OTD)
› Angle of Arrival (AOA) positioning
› Reference Node Based Positioning (RNBP)
› Assisted Global Positioning System (Assisted GPS)
298.11.2002Antti Siitonen, 2002
Accuracy of different positioning systems
Accuracy
10m 100m 1 km 10 km
GPSTA/Rx
E-OTD Cell-ID
› Always an estimate
› Different methods for different usage
› Most accurate isn’t always the best choise
308.11.2002Antti Siitonen, 2002
UMTS System architecture for LCS
BSC
SS7
HLR VAS
GSMInternet
LAN
GPRS
PSTN
3G MSC
SGSN GGSN
RNC
UTRA
MS
UE
BTS
BS
Circuit Switched Domain
Packet Switched Domain
Camel, WAP, MExE, USATLCSExt. Client
SRNC/SMLC
GMLC
SMLC = Serving Mobile Location CentreGMLC = Gateway Mobile Location CentreLCS
Internal Client
318.11.2002Antti Siitonen, 2002
MExE
› Terminals will have different capabilities - how to tell to the service which are the current capabilities?
› Mobile Application Execution Environment (MExE) was introduced to handle terminal capabilities
› MExE Classmark 1: Numeric keypad, limited screensize, fixed character amounts (WAP type Terminal)
› MExE Classmark 2: Colour screen, full keypad, wide application support (JAVA supporting terminal)
› MExE Service Environment: Set of supported services
› Personalisation database - interacts with USIM
328.11.2002Antti Siitonen, 2002
USAT
› USIM Application Toolkit
› Extension to GSM SIM Application Toolkit to support USIM properties
› Applications executed in USIM
› Most likely to be “closed” environment - operators are in control of USAT applications
338.11.2002Antti Siitonen, 2002
CAMEL SCE
Customised Applications for Mobile network Enhanced Logic- Developed to provide automatic roaming with full service set- Mobility and Service Portability on top of IN
Subscriber Locationand State Retrieval
CAMEL - functioningenvironment
Subscription DataHandling
Mobility ManagementSMS - MMS
GPRS-interworking
Circuit SwitchedCall Control
348.11.2002Antti Siitonen, 2002
Virtual Home Environment
› Idea: To have the same, personalised individual interface through theterminal regardless of the UMTS network the user is attached to
› Requirements for Release 99 based network are based on CAMEL
› Subscriber profiles are handled in MExE Service Environment
› Location Based Services information can be transferred through CAMEL
› Provisioned services and their usage information is transferred between Networks through CAMEL
› Number portability can be handled through CAMEL
› Question:
› Would this be easier in All IP environment?
358.11.2002Antti Siitonen, 2002
Service Concepts
› GSM inherited Services supported in R99 are quite BASIC:
› Voice
› FAX
› Alternate FAX/Voice
› Circuit Switched Data Bearer services
› Supplementary Services
› USSD (Unstructured Supplementary Service Data)
› MMS
› Packet Switched Services are actually same as in GPRS, but
› Bigger bit rate
› Smaller delay
368.11.2002Antti Siitonen, 2002
UMTS Security
›There are three key principles behind 3G security:
› 3G security will build on the security of second generationsystems. Security elements within GSM and other second-generation systems that have proved to be needed and robust shall be adopted for 3G security.
› 3G security will improve on the security of second generationsystems - 3G security will address and correct real and perceived weaknesses in second generation systems.
› 3G security will offer new security features and will secure new services offered by 3G.
378.11.2002Antti Siitonen, 2002
UMTS Security (cont.)
› High Level objectives of security:
› To ensure that information generated by or relating to a user is adequately protected against misuse or misappropriation;
› Environments are adequately protected against misuse or misappropriation;
› To ensure that the security features standardised are compatible with world-wide availability. (There shall be at least one ciphering algorithm that can be exported on a worldwide basis (in accordance with the Wassenaar agreement));
› To ensure that the security features are adequately standardised to ensure world-wide interoperability and roaming between different serving networks;
› To ensure that the level of protection afforded to users and providers of services is better than that provided in contemporary fixed and mobilenetworks (including GSM);
› To ensure that the implementation of 3GPP security features and mechanisms can be extended and enhanced as required by new threats and services.
388.11.2002Antti Siitonen, 2002
Protocol architectures in UMTS
UE BS RNC MSC/SGSN GMSC/GGSN
Transport Network Layer
Radio Network Layer
System Network Layer
User Plane Control Plane
User & Control planes are parallel
398.11.2002Antti Siitonen, 2002
Transport Network Protocol Architecture›R99
WCDMA Physical Layer Physical Layer (PDH or SDH)
MAC
RLC
MAC
RLCATM or UDP/IP
AAL (n) or GTP-U
WCDMA Physical Layer Physical Layer (PDH or SDH)
MAC
RLC
MAC
RLC
ATM or IP
SCCP
ATM or IP
SCCP
MTP
SCCP
MTP
SCCP
User plane protocols in transport network
Control plane protocols in transport network
RLC = Radio Link Control, MAC = Medium Access Control, SCCP = Signalling Connection Control Part
Uu Iub/Iur Iu Gn
Uu Iub/Iur Iu D/Gr HLR
UE
UE
BS
BS RNC
RNC
MSC/SGSN
SGSNGGSN
ATM or UDP/IP
AAL (n) or GTP-U
ATM or UDP/IP
AAL (n) or GTP-U
ATM or UDP/IP
AAL (n) or GTP-U
408.11.2002Antti Siitonen, 2002
Protocol layers
› Physical layers
› WCDMA Physical Layer
› PDH or SDH Physical Layer
› MAC
› Set of logical channels
› RLC
› Radio Link Control» eg. Segmentation and reassembly, Error correction,..
› UMTS is primarly specified to use ATM as Layer3-protocol
› IP is defined for user data and there is an IP option for signalling transport
418.11.2002Antti Siitonen, 2002
System Network Protocols
› Mobility Management -protocol (MM)
› Between UE and MSC
› Basic mechanisms for Mobility management and authentication functions
› GPRS Mobility Management -protocol (GMM)
› Mobility mangement for Packet Switched domain
› Call Control -protocol (CC)
› Between UE and MSC
› Basic Mechanisms for Call Control in Circuit Switched domain
› Session Management -protocol (SM)
› Between UE and SGSN
› Supplementary Services -protocol (SS)
› Between UE and MSC
› Additional services in Circuit Switched domain
428.11.2002Antti Siitonen, 2002
Role of IP in UMTS evolution
Traffic Control
Traffic Transport
Traffic Control
User Traffic & Services
Traffic Transport
User Traffic & Services
R99 R4
Traffic Transport
Traffic Control
User Traffic & Services
R5/6
Role of IP
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All-IP
› In UMTS R5
› IPv6-support mandatory
› IPv4-support optional
› Signalling
› Interface to external networs via SIP
› Towards PSTN SIP over IP is translated to SS7 Call Control -signalling (eg. ISUP)
› IPSec is needed to ensure integrity of SIP-sessions» Still no decision of end-to-end multimedia session ciphering
448.11.2002Antti Siitonen, 2002
SIP services
› Session Initiation Protocol based signalling
› VoIP
› Instant messaging
› Presence information
› Browser sessions
› SIP based services (examples)
› Rich Call
› Multimedia conference/Chat
458.11.2002Antti Siitonen, 2002
IP Multicast Architecture – Multicast connections example: 5 users, 1 group.
IP Multicast Network
GGSN
GGSN
SGSN
SGSN
SGSN
SGSN
RNC
RNC
RNC
RNC
RNC
RNC
RNC
Radio Bearer (Broadcast)
Multicast_RAB
Multicast_GTP_Tunnel
IP Multicast
468.11.2002Antti Siitonen, 2002
UMTS for mobile operator
› New investments to the network
› New set of subscribers and services
› Several service networks - serveral service mechanisms
› New security challenges in IP: Everything cannot be blocked out, IP has more flexibility
› Number of IP connected devices will be greater than number of individuals in the network
IS THERE GOOD ALTERNATIVES?- For Mobile use, not yet.- For Wireless Connectivity, yes there is.
To be continued in the next lecture ..