Transcript Review, UTRAN Interfaces

Southern Methodist University Fall 2003
EETS 8316/NTU CC745-N
Wireless Networks
Lecture 12: EDGE
Instructor: Jila Seraj
email: [email protected]
http://www.engr.smu.edu/~jseraj/
tel: 214-505-6303
EETS 8316/NTU TC 745, Fall 2003
SMU
ENGINEERING
#1
Housekeeping
Exam 12/04 at 6:30 pm
Duration one hour
Distant students can take it anytime before
12/17. Please contact your proctor
immediately. The exam is available from
12/04.
Homework #3 is on the web. Deadline Dec
5th for in-campus students and Dec 12th for
others.
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#2
Outline
EDGE
Classic and Compact
GERAN
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#3
Review, UMTS Architecture
CN
CN : Enhanced GSM/GPRS CN
Iu
UTRAN
RN: UTRAN
Uu
UE
UTRAN
CN
UE
UMTS Terrestrial Radio Access Network
Core Network
User Equipment
EETS 8316/NTU TC 745, Fall 2003
SMU
ENGINEERING
#4
Review, UMTS reference model
Application
services
2G network
Roaming
GW
HLR
IP
CSCF
RAN
Iu
3G
SGSN
3G
GGSN
3G MSC
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
PSTN
GW
PSTN
#5
Review, UMTS reference model
CSCF = Call State Control Function
responsible for call state control functions,
service switching function, address translation,
vocoder negotiation to support VoIP
Call state is a set of states identified in the
process of completing a call. Obvious
examples of call state are: Call attempt, Called
number reception, Called number translation,
Feature Activation, Called party Alert, through
connection, Calling Party Release, etc…
EETS 8316/NTU TC 745, Fall 2003
SMU
ENGINEERING
#6
Review, UTRAN Architecture
Core Network
Iu
Iu
RNS
Iur
RNS
RNC
RNC
Iub
Node B
EETS 8316/NTU TC 745, Fall 2003
Iub
Iub
Node B
Node B
SMU
ENGINEERING
Iub
Node B
#7
Review, Functions of UTRAN Components
RNC
— Uplink/downlink signal transfer, mobility,
soft handoff
—Upper outer loop/ downlink power control,
—Common control channels
—Very similar to BSC functions
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#8
Review, Functions of UTRAN Components
Node B:
— Logical node, maintains link with UE
— Responsible for radio transmission for one
or more cells, adds/removes radio links on
demand,
— Mapping logical resources to physical
resources,
— Upper inner loop power control,
— Interconnecting UE from different
manufacturers.
—Similar to BTS function
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#9
Review, UTRAN Interfaces
Uu: Between Node B and UE (WCDMA)
Iub: Between Node B and RNC (ATM)
Iur: Between various RNCs (ATM)
Iu: Between the Core Network and the
RNC (IP over ATM)
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#10
Review, Protocol Model for UTRAN Interfaces
UTRAN consists of
—Radio Network Layer (specific to UTRAN
itself)
—Transport Network Layer (standard
technology: ATM)
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#11
Review, Protocol Model for UTRAN Interfaces
The UTRAN specific protocols include
—Radio Access Network Application Part:
Radio Network Signaling over the Iu.
—Radio Network Subsystem Application Part:
Radio Network Signaling over the Iur.
—Iub interface uses node B application
protocol (NBAP).
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#12
Review, UTRAN Interfaces
Iur Interface (RNC <-> RNC)
—point-to-point open interface,
—macro-diversity support,
—transport signaling for mobility and radio
resource allocation.
Node
B
Iub
RNC
Node
B
Node
B
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
Iu
Iur
RNC
#13
Review, UTRAN Interfaces
Iub Interface (RNC <-> Node B)
— interconnection of equipment from different
manufacturers,
— allows Abis (GSM/GPRS transmission
sharing),
— transports DCH, RACH, FACH and DSCH
data,
— enables negotiation of radio resources
between node B and RNC
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#14
EDGE
EDGE= Enhanced Data rates for Global
Evolution
EGPRS = Enhanced General Packet Radio
Services
EDGE is an enhancement to GPRS
Maximum of 473 kbps if all 8 time slots are
used
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EDGE
 Introduces concept of “Link Adaptation”
in wireless for maximum throughput in
variable radio conditions
 The data rates are tripled. The magic is in
introduction of 8-PSK modulation that can
carry 3 bits per symbols
 8-PSK = Octagonal Phase Shift Keying
EGPRS impact is mainly in RF and MAC
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#16
GSM EDGE Radio Access Network
GERAN = GSM EDGE Radio Access
Network
Motivation
—All IP Network
—Low cost of operation
—One platform
—support of new services
—Support for different access networks
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#17
Requirements GERAN
Spectrum efficient support for VoIP, (endto-end IP-based voice service), Quality 
TDMA
Support of new IP multimedia services,
Future proof
Alignment with UMTS/UTRAN service
classes and QoS
Common GPRS and GSM Core Network for
EDGE and UTRAN
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#18
Requirements on GERAN ..
Integration of all services over IP
infrastructure
Support for COMPACT and
VoIP/COMPACT
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#19
GERAN
GERAN connects to PS CN through
Iu-ps for R4 and R5 terminals (New
protocols) and Gb for R97 and R99
Iu-ps
terminals (LLC and SNDCP
protocols)
GERAN
TE
MT
R
Um
BSS
Gb
Iu-cs
A
GERAN connects to CS CN
through Iu-cs or A
EETS 8316/NTU TC 745, Fall 2003
SMU
3G SGSN
SGSN Server
MGW
SGSNN
3G MSC
MSC Server
MGW
MSC
ENGINEERING
#20
GERAN Interfaces
Gb
—GPRS interface not suitable for RT
transmission
—LLC+RLC both ARQ protocols
—IP instead of FR
 Iu-ps
—UTRAN PS, IP, QoS, AAL5/ATM , possibly IP
over SDH
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#21
New Features in EGPRS Rel 4.
Delayed TBF Release
—In bursty traffic, many call set up and
release makes inefficient use of resources.
By delaying release of TBF, and sending
dummy LLC frames to mobile, the link is
kept alive.
Network Assisted Cell Change (NACC)
— When sending neighbour information, cell system
information is also sent to mobile. When handing
off, mobiles has all the data it needs. Speeds up
handoff.
EETS 8316/NTU TC 745, Fall 2003
SMU
ENGINEERING
#22
New Features in EGPRS Rel 5
Delayed TBF Release
—In bursty traffic, many call set up and
release makes inefficient use of resources.
By delaying release of TBF, and sending
dummy LLC frames to mobile, the link is
kept alive.
Network Assisted Cell Change (NACC)
— When sending neighbour information, cell system
information is also sent to mobile. When handing
off, mobiles has all the data it needs. Speeds up
handoff.
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#23
COMPACT System Concept
First 200 kHz carrier
—1/3 reuse.
—CPBCCH (Compact Packet BCCH) Transmits
discontinuously ( at certain time).
—Synchronization of base stations and time split
into four time groups provide an effective 4/12
reuse for broadcast and common control
channels.
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#24
COMPACT System Concept
—All Traffic and dedicated channels on the rest of
TS are reuse 1/3.
Support for paging for TDMA/136 circuit
switched.
Minimum deployment: 3 carriers, 0.6 MHz plus
guard bands.
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#25
EDGE Compact
There is a Base station synchronization
concept in GSM
—GSM BTS synch is used only on the traffic
channels TCH that has FH in Fractional loading
planning (FLP)to avoid Co-channel and
adjacent channel interference in reuse 1/3 and
smaller.
—The BCCH is transmitting continuously with
5/15 and higher reuse.
EETS 8316/NTU TC 745, Fall 2003
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#26
Reuse 1/3
EETS 8316/NTU TC 745, Fall 2003
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#27
Compact
EETS 8316/NTU TC 745, Fall 2003
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#28
Evolution of 2G Cellular Technologies
2G
3G
IS-95B
CDMA
GSM
cdma2000
W-CDMA
FDD
TDD
GPRS
IS-136
TDMA
EETS 8316/NTU TC 745, Fall 2003
EDGE & 136
HS outdoor
UWC-136
SMU
ENGINEERING
136 HS
indoor
#29
Quality-of-Service: What, Why?
Quality of Service (QoS) is the ability of a
network element (e.g. an application, host or
router) to have some level of assurance that
its traffic and service requirements can be
satisfied.
• Newer applications with multimedia content
• Demands of convergence
• More bandwidth ?
• User perception of service quality can be
translated to network flow parameters such as
delay and delay variation.
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#30
Guidelines for providing QoS to users
•QoS perceived by the user must be end-toend.
• Parameters defining QoS of a flow must be
fewer and simpler.
• QoS definition must be compatible with all
kinds of applications.
• Must be able to quantify and enforce.
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#31
UMTS-specific requirements (contd.)
•QoS parameter control on peer to peer basis
between mobile and 3G gateway node
• UMTS QoS control mechanism should map
applications QoS profile to UMTS services.
Applications may be required to state their QoS
requirement.
• UMTS QoS capable services should work with
other networking architectures.
• Only finite set of QoS definitions supported.
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#32
UMTS-specific requirements (contd.)
• Multiple traffic streams per session.
• Lower overhead for QoS related operations;
higher resource utilization.
• Re-negotiation should be possible after QoS
parameter values have been agreed upon dynamic QoS.
• User mobility should be supported in the QoS
framework.
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#33
Traffic cases for QOS
Conversational
RT media, delay sensitive delay variation
sensitive (VoIP, Conferencing,..)
Streaming
Delay variations sensitive Audio and video
relaxed absolute delay than conversational
(buffering required)
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#34
Traffic cases for QOS
Interactive
none real time, delay sensitive (WWW, ftp, remote
databases, ..)
Background
none RT (e.mail, SMS, ftp,..)
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#35
QoS attributes for Traffic Classes
Traffic Class
Maximum bit
rate
Guaranteed bit
rate
Delivery order
Transfer delay
Conversational
Streaming
x
x
x
x
Yes
Yes
x
x
Traffic handling
priority
Allocation/
retention
priority
Source statistics
descriptor
EETS 8316/NTU TC 745, Fall 2003
Interactive Background
x
x
No
No
x
x
x
x
x
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ENGINEERING
x
x
#36
QoS Characteristics of UMTS Classes
Very important
1
0.9
Conversational
Streaming
Interactive
Background
0.8
0.7
0.6
0.5
0.4
0.3
less important
0.2
0.1
0
delay
EETS 8316/NTU TC 745, Fall 2003
throughput
SMU
ENGINEERING
retransmission
#37
QoS supported
Interactive
supported in R99
Background
supported in R99
Conversational
R5
Streaming
R4
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#38
Useful Links
http://www.3gpp.org/TB/GERAN/GERAN.
htm
http://www.3gpp.org/
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#39
WAP
Wireless Access Protocol (WAP
Started with Ericsson, Nokia and Motorola
WAP goal is
—Open standards
—Internet WWW application development
model
—Wireless network technology and bearer
independence
—Device independence
—Embrace and extend existing standards
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#40
WAP (cont)
Strength
—Widespread presentation
—90% of all handset manufacturers are
committed
—Carriers representing nearly 100 million
subscribers worldwide have joined WAP
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#41
WAP (cont)
Why not adopt internet protocols?
Limitations of wireless handheld devices
—Small display
—Limited memory
—Limited keyboard
Limitations of wireless networks
—Limited bandwidth
—High latency
—Limited computing environment
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#42
Benefits of WAP
WWW-based applications
Interoperability across network types
Efficient use of wireless network resources
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#43
Key Features of WAP
Markup language
Script Language
—Designed to create services for small
handheld terminals
Wireless technology applications
framework
—Access to telephony related functions
Lightweight protocol stack
—designed to minimize required bandwidth
and impact on latency
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#44
WAP Architecture
Client
WAP
User
Agents
WAP
Protocol
Stack
WSP
Request
WAP
Gateway/
Proxy
Encoders
Decoders
WSP
Response
EETS 8316/NTU TC 745, Fall 2003
Protocol
Conversion
SMU
ENGINEERING
Origin
Server
HTTP
Request
CGI
Scripts
HTTP
Response
WML
WMLcript
#45
WAP Protocols and Standards
WAP stack design goal
Avoid establishment and tear down phases
—Optimize for short request-response
transactions
Support wide range of wireless networks
—Datagram is the most common transport
service
Minimize number of packets sent over the air
—Moving data around is expensive
—Avoid resending same (static) information
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#46
WAP Protocols and Standards (cont)
HTTP
Wireless Session Protocol (WSP)
Wireless Transaction Protocol (WTP)
TLS-SSL
UDP
IP
Wireless Transport Layer Security (WTLS)
Wireless Datagram
Protocol (WDP)
UDCP
USSD
EETS 8316/NTU TC 745, Fall 2003
UDP
IP (ICMP)
SMS
SMU
Etc
ENGINEERING
GPRS CDPD
#47
WAP Protocols and Standards (cont)
Runs over wireless networks including
GSM, SMS/USSD and IP networks
Has minimal requirements on bandwidth
and CPU power
Is based on HTTP/1.1 with necessary
enhancement
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#48
Wireless Application Environment (WAE)
Wireless markup language (WML)
—Lightweight markup language similar to
HTML. Optimized for hand-held mobile
devices
WML script
—Similar to Java Script, light weight scripting
language
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#49
Wireless Application Environment (WAE)
Wireless Telephony Application (WTA,
WTAI)
—A framework and programming interface for
telephony services
Wireless BitMaP (WBMP)
EETS 8316/NTU TC 745, Fall 2003
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ENGINEERING
#50