4G Introduction
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Transcript of 4G Introduction
4GA historical and practical guide
PrologueEvolution To Mobile Operator
10 MHz
Set up a podcast to provide your family weekend entertainment, kind of like a 1G provider
PrologueEvolution To Mobile Operator
1 MHz
now neighbors want to join
You use FDMA to provide 10 neighbors
PrologueEvolution To Mobile Operator
1 MHz
more neighbors want to join
You use TDMA on each 1MHz carrierbecause not everyone is using
it the same time anyway
PrologueEvolution To Mobile Operator
Far far away friends want to join
Mobility, security, policy control, planning… Congratulations! You are now a mobile operator!
A Little History: 1G• 1980
• Lack of roaming: various local systems
• Bad security
• Poor battery
https://img1.etsystatic.com/005/0/6011536/il_340x270.400991407_ig0s.jpg
A Little History: 2G• 1990, it’s all about voice, good voice and roaming voice
• GSM: Global System for Mobile Communications, the success of mobile
• FDD/TDMA-FDMA
• SMS
• 10^2 kbit/s
http://upload.wikimedia.org/wikipedia/commons/thumb/d/d1/Gsm_structures.svg/350px-Gsm_structures.svg.png
Problem of 2G
• 2G focus on voice, results in an air interface very inefficient for data packet
• Various advances in MAC layer technology, notably CDMA
Voice Data
Bit Rate small CBR Variable BRCan be large
Band Width 64 Kbit/s 2Mbit/s
Packet small large
Delay small depends
CDMA• Better auto correlation
• Low cross correlation between different spread code’s output signal
• Frequency reuse factor of 1 (as oppose to 4 in GSM)
• Improved security
• Hard to be jammed
Input Signal
Spreading Code
Output Signal
A Little History: 3GThe Vision
The Martini Vision: Anyone, Anywhere, Any Medium
A Little History: 3G
IMT 2000 family Common term mode of operation
中華電信
IMT-DSDirect Sequence
CDMAW-CDMA FDD v
IMT-MCMulti Carrier
CDMACdma2000 FDD v
IMT-TDTime Devision
CDMATD-CDMA TD-SCDMA TDD
IMT-SCSingle Carrier EDGE FDD
IMT-FTFrequency Time DECT TDD
In Reality
3G: UMTSUniversal Mobile Telecommunications System
UE NodeB SGSN GGSNInternet
HLR
MSC GMSC
User Equipment
Serving GPRSSupport Node
Gateway GPRSSupport Node
Packet Data Network(packet Switch Stream, IP Multimedia System)
UTRAN Core Network
UE NodeB
UE NodeB
RNC
RNC
Public Phone
Network
Signaling Network
Mobile Switching Center
Gateway MSC
Home Location Register
Radio Network
Controller
3G: UMTSUniversal Mobile Telecommunications System
UE NodeB SGSN GGSNInternet
HLR
MSC GMSC
User Equipment
Serving GPRSSupport Node
Gateway GPRSSupport Node
Packet Data Network(packet Switch Stream, IP Multimedia System)
UTRAN Core Network
RNC
Public Phone
Network
Signaling Network
Mobile Switching Center
Gateway MSC
Home Location Register
• You bought a phone right outside NTHU, turn it on
• Your subscription is based on a 15 digits number in your SIM.
• After the phone found network, the number is sent to HLR.
• Your phone and HLR now share the same key for communication.
Radio Network
Controller
3G: UMTSUniversal Mobile Telecommunications System
UE NodeB SGSN GGSNInternet
HLR
MSC GMSC
User Equipment
Serving GPRSSupport Node
Gateway GPRSSupport Node
Packet Data Network(packet Switch Stream, IP Multimedia System)
UTRAN Core Network
RNCRadio
Network Controller
Public Phone
Network
Signaling Network
Mobile Switching Center
Gateway MSC
Home Location Register
• First you make a call to inform your dad 付清節快樂 (happy father’s paying day)
• Your UE requests MSC about a particular number.
• MSC checks with HLR to see if you are permitted to call.
• MSC set up resources required in RAN (radio access network) and CN (core network).
• When the call ends, MSC and GMSC are involved in producing call detail record.
3G: UMTSUniversal Mobile Telecommunications System
UE NodeB SGSN GGSNInternet
HLR
MSC GMSC
User Equipment
Serving GPRSSupport Node
Gateway GPRSSupport Node
Packet Data Network(packet Switch Stream, IP Multimedia System)
UTRAN Core Network
RNCRadio
Network Controller
Public Phone
Network
Signaling Network
Mobile Switching Center
Gateway MSC
Home Location Register
• Now you are riding your scooter back to NCTU.
• After a while idle, your phone moves from Mobility Management (MM) connect to MM-IDLE. To avoid excessive location update, few NodeB’s are grouped into a location area. Location update happens only when you enter new location area.
• So your phone happily sits idle and listen if it receives call or location update.
3G: UMTSUniversal Mobile Telecommunications System
UE NodeB SGSN GGSNInternet
HLR
MSC GMSC
User Equipment
Serving GPRSSupport Node
Gateway GPRSSupport Node
Packet Data Network(packet Switch Stream, IP Multimedia System)
UTRAN Core Network
RNCRadio
Network Controller
Public Phone
Network
Signaling Network
Mobile Switching Center
Gateway MSC
Home Location Register
• When your dad tries to call you (he decides he don’t won’t to pay for this cell phone), GMSC looks up HLR to see which MSC is serving you. All NodeB’s of that location area broadcast to wake up your cellphone.
• During call, you are constantly moving, so hand over is required. In CDMA, you are often connected to multiple cell towers at once, this facilitates soft handover.
3G: UMTSUniversal Mobile Telecommunications System
UE NodeB SGSN GGSNInternet
HLR
MSC GMSC
User Equipment
Serving GPRSSupport Node
Gateway GPRSSupport Node
Packet Data Network(packet Switch Stream, IP Multimedia System)
UTRAN Core Network
RNCRadio
Network Controller
Public Phone
Network
Signaling Network
Mobile Switching Center
Gateway MSC
Home Location Register
• Now you are wondering what is RNC, so you open your browser.
• To send or receive packets, a PDP (packet data protocol) context need to be established.
• PDP context signals SGSN and GGSN to set up context for packet data session. Context include a subscriber IP and a QoS request.
• After done browsing, you deactivates the PDP context.
3G: UMTSUniversal Mobile Telecommunications System
UE NodeB SGSN GGSNInternet
HLR
MSC GMSC
User Equipment
Serving GPRSSupport Node
Gateway GPRSSupport Node
Packet Data Network(packet Switch Stream, IP Multimedia System)
UTRAN Core Network
RNCRadio
Network Controller
Public Phone
Network
Signaling Network
Mobile Switching Center
Gateway MSC
Home Location Register
• QoS request is simply ignored by most (all) operators.
3G: UMTSUniversal Mobile Telecommunications System
UE NodeB SGSN GGSNInternet
HLR
MSC GMSC
User Equipment
Serving GPRSSupport Node
Gateway GPRSSupport Node
Packet Data Network(packet Switch Stream, IP Multimedia System)
UTRAN Core Network
RNCRadio
Network Controller
Public Phone
Network
Signaling Network
Mobile Switching Center
Gateway MSC
Home Location Register
• Now mobile operator is sending you a SMS message to inform about the data usage volume.
• GGSN checks HLR to obtain your routing area, but also obtains that you have no PDP context active. A paging message is broadcast requesting your phone to set up PDP context so that the message can be sent.
Key notes on 2G/3G2G 3G
Data Rate 10 kbit/s 10 kbits/s
MAC Scheme TDMAFDMA CDMA
Available Bandwidth
2x5 MHzwith TDMA 2x15 MHz
Cost and Market see next few slides
2 4
Bandwidth: 2G vs 3Gtype bandwidth winning bid
(in billion) winner
A W-CDMA 2 x 15MHz+ 5MHz 10.2 遠致
B W-CDMA 2 x 10MHz+ 5MHz 7.7 聯邦
C W-CDMA 2 x 15MHz+ 5MHz 10.3 台灣
D W-CDMA 2 x 15MHz+ 5MHz 10.2 中華
E CDMA2000 2 x 20MHz 10.6 亞太
2G1. About to be “recycled”
2. At the time CHT got its 2G license. It is still government run.
3G: around 49 billion NTD
Revenue: 2G vs 3G
3G growth
• Question: Why is it growing like this? Slow, exponential, finally slow.
Problem with 3G• Why has it been slow to take off?
Small coverage, lack of cheap and power friendly terminal, lack of killer app
• W-CDMA cell breathing frequency reuse factor of 1 -> all senders and receivers interfere with each other-> number of UE affects edge data rate-> making cell tower planning more difficult
• Packet network scalabilityGGSN is a huge gateway that last for a long time (it is not just a bottle neck, it is a static battle neck…)
LTE• It is not 4G
ITU made it clear… LTE is part of IMT-2000 3G family. We call LTE 3.9G, because despite its enormous improvement on bandwidth (around 50 Mbit/s), it did not meet 4G standard (100 Mbit/s).
• It is designed to expect an all-packet-switching network.3G was designed for both, but is in fact very inefficient on IP.
• TLACongratulations, you are ready for more TLA’s (three letter acronym).
3GPP
LTE
EPS
E-UTRAN
SAE
EPC
Release 8
Third Generation Partnership Project
Long Term Evolution System Architecture Evolution
Evolved Packet CoreEvolved UTRAN
Evolved Packet System
3GPP
LTE
EPS
E-UTRAN
SAE
EPC
Release 8
Third Generation Partnership Project
Long Term Evolution System Architecture Evolution
Evolved Packet CoreEvolved UTRAN
Evolved Packet System
Term used for marketing
3GPP
LTE
EPS
E-UTRAN
SAE
EPC
Release 8
Third Generation Partnership Project
Long Term Evolution System Architecture Evolution
Evolved Packet CoreEvolved UTRAN
Evolved Packet System
Terms withactual meaning
Terms withactual meaning
Term should have been used
for marketing
EPS Architecture
UE e-NodeB
MME
S-GW P-GW
PDN(PSS, IME)
HSS
E-SMLC GMLC
User Equipment Evolved NodeB Serving Gateway PDN Gateway Packet Data Network(packet Switch Stream, IP Multimedia System)
E-UTRAN Core Network (EPC)
MobilityManagement
Entity
HomeSubscriber
Server
Evolved ServingMobile Location Center
Gateway MobileLocation Center
EPS Architecture
UE e-NodeB
MME
S-GW P-GW
PDN(PSS, IME)
HSS
E-SMLC GMLC
User Equipment Evolved NodeB Serving Gateway PDN Gateway Packet Data Network(packet Switch Stream, IP Multimedia System)
E-UTRAN Core Network (EPC)
MobilityManagement
Entity
HomeSubscriber
Server
Evolved ServingMobile Location Center
Gateway MobileLocation Center
So called “cell phone” but could be other devices
On a UE, UMSI: Unique Mobility Subscriber Id identifies a subscriber. UMEI: Unique Mobility Equipment Id identifies equipment. UMEI can be obtained by typing *#06#
EPS Architecture
EPS Architecture
UE e-NodeB
MME
S-GW P-GW
PDN(PSS, IME)
HSS
E-SMLC GMLC
User Equipment Evolved NodeB Serving Gateway PDN Gateway Packet Data Network(packet Switch Stream, IP Multimedia System)
MobilityManagement
Entity
HomeSubscriber
Server
Evolved ServingMobile Location Center
Gateway MobileLocation Center
So called “cell tower”
e-NodeB • Provide radio access to UE’s (Uu interface). • Interface: logical connection between
endpoint.
Uu
S1-MME
S1-U
E-UTRAN Core Network (EPC)
EPS Architecture
UE e-NodeB
MME
S-GW P-GW
PDN(PSS, IME)
HSS
E-SMLC GMLC
User Equipment Evolved NodeB Serving Gateway PDN Gateway Packet Data Network(packet Switch Stream, IP Multimedia System)
E-UTRAN Core Network (EPC)
MobilityManagement
Entity
HomeSubscriber
Server
Evolved ServingMobile Location Center
Gateway MobileLocation Center
Control Traffic
Uu S1-U
S1-MME
Data
e-NodeB • Separate control plan and data plan. • Tunnels control traffic between UE and MME
(S1-MME interface). • Tunnels data between UE and services
(S1-U interface).
So called “cell tower”
EPS Architecture
UE e-NodeB
MME
S-GW P-GW
PDN(PSS, IME)
HSS
E-SMLC GMLC
User Equipment Evolved NodeB Serving Gateway PDN Gateway Packet Data Network(packet Switch Stream, IP Multimedia System)
E-UTRAN Core Network (EPC)
MobilityManagement
Entity
HomeSubscriber
Server
Evolved ServingMobile Location Center
Gateway MobileLocation Center
Control Traffic
Uu S1-U
S1-MME
Data
e-NodeB • Concert with other eNodeB’s to handle
mobility (X-2 interface).
So called “cell tower”
UEUser Equipment
Uue-NodeB
X-2
Control Traffic
Data
EPS Architecture
UE e-NodeB
MME
S-GW P-GW
PDN(PSS, IME)
HSS
E-SMLC GMLC
User Equipment Evolved NodeB Serving Gateway PDN Gateway Packet Data Network(packet Switch Stream, IP Multimedia System)
E-UTRAN Core Network (EPC)
MobilityManagement
Entity
HomeSubscriber
Server
Evolved ServingMobile Location Center
Gateway MobileLocation Center
Uu S1-U
S1-MME
MME • Keep track of UE’s. • Setting up and tearing down sessions.
S11
S6a
S5 SGi
EPS Architecture
UE e-NodeB
MME
S-GW P-GW
PDN(PSS, IME)
HSS
E-SMLC GMLC
User Equipment Evolved NodeB Serving Gateway PDN Gateway Packet Data Network(packet Switch Stream, IP Multimedia System)
E-UTRAN Core Network (EPC)
MobilityManagement
Entity
HomeSubscriber
Server
Evolved ServingMobile Location Center
Gateway MobileLocation Center
Uu S1-U
S1-MME
MME • Authentication and gate keeping.
S11
S6a
S5 SGi
EPS Architecture
UE e-NodeB
MME
S-GW P-GW
PDN(PSS, IME)
HSS
E-SMLC GMLC
User Equipment Evolved NodeB Serving Gateway PDN Gateway Packet Data Network(packet Switch Stream, IP Multimedia System)
E-UTRAN Core Network (EPC)
MobilityManagement
Entity
HomeSubscriber
Server
Evolved ServingMobile Location Center
Gateway MobileLocation Center
Uu S1-U
S1-MME
MME • Selecting S-GW and P-GW. • Primary responsibilities are divided into
EMM (Evolved Mobility Management) and ESM (Evolved Session Management).
• A user is on al most one MME at all time.
S11
S6a
S5 SGi
UE e-NodeB
MME
S-GW P-GW
PDN(PSS, IME)
HSS
E-SMLC GMLC
User Equipment Evolved NodeB Serving Gateway PDN Gateway Packet Data Network(packet Switch Stream, IP Multimedia System)
E-UTRAN Core Network (EPC)
MobilityManagement
Entity
HomeSubscriber
Server
Evolved ServingMobile Location Center
Gateway MobileLocation Center
Uu S1-U
S1-MME
HSS • Database of subscriber information. • Queried by MME. • Holds security information of all SIM cards
of a mobile network. • Keeps a “birds eye view” of what users are
located in what network (i.e. what SIM is registered with which MME). Similar to HLR in UMTS.
S11
S6a
S5 SGi
EPS Architecture
UE e-NodeB
MME
S-GW P-GW
PDN(PSS, IME)
HSS
E-SMLC GMLC
User Equipment Evolved NodeB Serving Gateway PDN Gateway Packet Data Network(packet Switch Stream, IP Multimedia System)
E-UTRAN Core Network (EPC)
MobilityManagement
Entity
HomeSubscriber
Server
Evolved ServingMobile Location Center
Gateway MobileLocation Center
Uu S1-U
S1-MME
S-GW • One or more S-GW’s can serve one or more
eNB’s. • One UE can be served by only one S-GW. • Receives instructions from MME to self up
and teardown UE sessions. • Handle signaling between MME and P-GW. • Handle IP packet between UE and P-GW.
S11
S6a
S5 SGi
EPS Architecture
UE e-NodeB
MME
S-GW P-GW
PDN(PSS, IME)
HSS
E-SMLC GMLC
User Equipment Evolved NodeB Serving Gateway PDN Gateway Packet Data Network(packet Switch Stream, IP Multimedia System)
E-UTRAN Core Network (EPC)
MobilityManagement
Entity
HomeSubscriber
Server
Evolved ServingMobile Location Center
Gateway MobileLocation Center
Uu S1-U
S1-MME
S-GW • One or more S-GW’s can serve one or more
eNB’s. • One UE can be served by only one S-GW. • Receives instructions from MME to self up
and teardown UE sessions.
S11
S6a
S5 SGi
EPS Architecture
UE e-NodeB
MME
S-GW P-GW
PDN(PSS, IME)
HSS
E-SMLC GMLC
User Equipment Evolved NodeB Serving Gateway PDN Gateway Packet Data Network(packet Switch Stream, IP Multimedia System)
E-UTRAN Core Network (EPC)
MobilityManagement
Entity
HomeSubscriber
Server
Evolved ServingMobile Location Center
Gateway MobileLocation Center
Uu S1-U
S1-MME
S-GW • Handle signaling between MME and P-GW.
S11
S6a
S5 SGi
EPS Architecture
UE e-NodeB
MME
S-GW P-GW
PDN(PSS, IME)
HSS
E-SMLC GMLC
User Equipment Evolved NodeB Serving Gateway PDN Gateway Packet Data Network(packet Switch Stream, IP Multimedia System)
E-UTRAN Core Network (EPC)
MobilityManagement
Entity
HomeSubscriber
Server
Evolved ServingMobile Location Center
Gateway MobileLocation Center
Uu S1-U
S1-MME
S-GW • Handle IP packet between UE and P-GW.
S11
S6a
S5 SGi
EPS Architecture
UE e-NodeB
MME
S-GW P-GW
PDN(PSS, IME)
HSS
E-SMLC GMLC
User Equipment Evolved NodeB Serving Gateway PDN Gateway Packet Data Network(packet Switch Stream, IP Multimedia System)
E-UTRAN Core Network (EPC)
MobilityManagement
Entity
HomeSubscriber
Server
Evolved ServingMobile Location Center
Gateway MobileLocation Center
Uu S1-U
S1-MME
P-GW • Provide access to external PDN • One UE can be associated with multiple P-
GW if it connect to multiple PDN’s. • Dictates the QoS and bandwidth parameter
for subscriber’s session.
S11
S6a
S5 SGi
EPS Architecture
UE e-NodeB
MME
S-GW P-GW
PDN(PSS, IME)
HSS
E-SMLC GMLC
User Equipment Evolved NodeB Serving Gateway PDN Gateway Packet Data Network(packet Switch Stream, IP Multimedia System)
E-UTRAN Core Network (EPC)
MobilityManagement
Entity
HomeSubscriber
Server
Evolved ServingMobile Location Center
Gateway MobileLocation Center
Uu S1-U
S1-MME
PCRS • The core function of a PCRF is to make
policy decisions for the network.That means it needs inputs (eg: from a subscriber database, from real-time network information, from a billing system, from local configuration) and it needs to translate that into a decision to direct the policy enforcer (PCEF) to take appropriate actions.
S11
S6a
S5 SGi
EPS Architecture
PCRS
Gx
UE e-NodeB
MME
S-GW P-GW
PDN(PSS, IME)
HSS
E-SMLC GMLC
User Equipment Evolved NodeB Serving Gateway PDN Gateway Packet Data Network(packet Switch Stream, IP Multimedia System)
E-UTRAN Core Network (EPC)
MobilityManagement
Entity
HomeSubscriber
Server
Evolved ServingMobile Location Center
Gateway MobileLocation Center
Uu S1-U
S1-MME
PCRS • What is the difference between PCRS and
PCEF in P-GW? • In CSFB, is PCRS involved? • Why can’t PCRS simply be a function of P-
GW?
S11
S6a
S5 SGi
EPS Architecture
PCRS
Gx
UE e-NodeB
MME
S-GW P-GW
PDN(PSS, IME)
HSS
E-SMLC GMLC
User Equipment Evolved NodeB Serving Gateway PDN Gateway Packet Data Network(packet Switch Stream, IP Multimedia System)
E-UTRAN Core Network (EPC)
MobilityManagement
Entity
HomeSubscriber
Server
Evolved ServingMobile Location Center
Gateway MobileLocation Center
Uu S1-U
S1-MME
AS vs NAS • AS (access stratum): link to link
communication. • NAS (non-access stratum): provide
communication between access network and core network. NAS makes the direct communication between MME and UE possible.
S11
S6a
S5 SGi
EPS Architecture
PCRS
Gx
UE e-NodeB
MME
S-GW P-GW
PDN(PSS, IME)
HSS
E-SMLC GMLC
User Equipment Evolved NodeB Serving Gateway PDN Gateway Packet Data Network(packet Switch Stream, IP Multimedia System)
E-UTRAN Core Network (EPC)
MobilityManagement
Entity
HomeSubscriber
Server
Uu
Evolved ServingMobile Location Center
Gateway MobileLocation Center
S1-U
S1-MME
Control plan - - - - - - - - - - User plan - - - - - - - - - -
S11
S6a
S5 SGi
EPS Architecture
UE e-NodeB
MME
S-GW P-GW
PDN(PSS, IME)
HSS
User Equipment Evolved NodeB Serving Gateway PDN Gateway Packet Data Network(packet Switch Stream, IP Multimedia System)
E-UTRAN Core Network (EPC)
MobilityManagement
Entity
HomeSubscriber
Server
Uu S1-U
S1-MMES11
S6a
S8 SGi
Roaming ScenarioRoaming User Foo
Visited Network (VPLMN,
visited PLMN)
Foo’s SubscribedNetwork (HPLMN, home public
land mobile network)
Architectural Comparison
UE e-NodeB
MME
S-GW P-GW
HSS
User Equipment Evolved NodeB Serving Gateway PDN Gateway
MobilityManagement
Entity
HomeSubscriber
Server
UE NodeB
SGSN GGSN
HLR
MSC GMSC
User Equipment
Serving GPRSSupport Node
Gateway GPRSSupport Node
RNCRadio
Network Controller
Signaling Network
Mobile Switching Center
Gateway MSC
Home Location Register
Control plan - - - - - - - - - - User plan - - - - - - - - - -
Architectural Comparison
UE e-NodeB
MME
S-GW P-GW
HSS
User Equipment Evolved NodeB Serving Gateway PDN Gateway
MobilityManagement
Entity
HomeSubscriber
Server
UE NodeB
SGSN GGSN
HLR
MSC GMSC
User Equipment
Serving GPRSSupport Node
Gateway GPRSSupport Node
RNCRadio
Network Controller
Signaling Network
Mobile Switching Center
Gateway MSC
Home Location Register
With X-2 interface, eNodeB’s can communicate with each other to handle mobility, so RNC is merged into eNodeB.
Architectural Comparison
UE e-NodeB
MME
S-GW P-GW
HSS
User Equipment Evolved NodeB Serving Gateway PDN Gateway
MobilityManagement
Entity
HomeSubscriber
Server
UE NodeB
SGSN GGSN
HLR
MSC GMSC
User Equipment
Serving GPRSSupport Node
Gateway GPRSSupport Node
RNCRadio
Network Controller
Signaling Network
Mobile Switching Center
Gateway MSC
Home Location Register
The forwarding function of MSC and SGSN is handled by S-GW, while the session management function is handled by MME.
Architectural Comparison
UE e-NodeB
MME
S-GW P-GW
HSS
User Equipment Evolved NodeB Serving Gateway PDN Gateway
MobilityManagement
Entity
HomeSubscriber
Server
UE NodeB
SGSN GGSN
HLR
MSC GMSC
User Equipment
Serving GPRSSupport Node
Gateway GPRSSupport Node
RNCRadio
Network Controller
Signaling Network
Mobile Switching Center
Gateway MSC
Home Location Register
GMSC and GGSN correspond to P-GW and HLR correspond to HSS is pretty much accurate.
2013年度綜合財報
2014 第三季股東說明會講稿
2015 ⼀一⽉月份營運報告 (內含2014⽉月營運報告)
Reference
1. 中華電信財務報表:http://www.cht.com.tw/ir/upload/files/CHT2013_AnnualReport_0528Chinese.PDF
2. Wisely, David. IP for 4G. John Wiley & Sons, 2009.
3. Kasera, Sumit, and Nishit Narang. 3G Mobile Networks: Architecture, Protocols and Procedures Based on 3GPP Specifications for UMTS WCDMA Networks. McGraw-Hill Professional Publishing, 2005.
4. Russell’s Youtube Channel: https://www.youtube.com/user/QuadraticSquared