beyond third generation telecommunications architectures
TRANSCRIPT
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Beyond Third GenerationBeyond Third GenerationTelecommunications Architectures:Telecommunications Architectures:
The Convergence of InternetThe Convergence of InternetTechnology and Cellular TelephonyTechnology and Cellular Telephony
Prof. Randy H. Katz
EECS DepartmentUniversity of California, Berkeley
Berkeley, CA [email protected]
http://www.cs.Berkeley.edu/~randy
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Presentation OutlinePresentation Outline
• Comparison of Telecomm & Data Comm Industries• Voice-centric versus Data-centric Viewpoint
• Internet versus Telephone Technology• Implications Beyond the Third Generation
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Presentation OutlinePresentation Outline
• Comparison of Telecomm & Data Comm Industries• Voice-centric versus Data-centric Viewpoint
• Internet versus Telephone Technology• Implications Beyond the Third Generation
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Global Telecommunications TradeGlobal Telecommunications Trade
0
20
40
60
80
100
120
1990 1991 1992 1993 1994 1995 1996
OtherNe t Se ttlementsEquipment
Source: ITU (The Economist, 8 March 1997)
$ Billions Total Revenue1996: $867 Billion2000: $1270 Billion
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Cellular Subscriber Growth in USCellular Subscriber Growth in US
85 87 89 91 93 95
0
10000
20000
30000
40000
50000
44 million
Source: CTIA Web Page
Cellular telephonyremains the hottest andfastest growing sector of the telecomm market
Nordic Countries: 10 mobilephones being added for
each wireline phone!
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Growth in Cell Sites in USGrowth in Cell Sites in US
85 87 89 91 93 95
0
5000
10000
15000
20000
25000
30000
35000
30000
Source: CTIA Web Page
25% growthin one yearrepresents
major marketfor infrastructure
vendors
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Mobile Telephone and Internet UsersMobile Telephone and Internet Users
0
100
200
300
400
500
600
1993 1994 1995 1996 1997 1998 1999 2000 2001
Source: Ericsson Radio Systems, Inc.
Mobile TelephoneUsers
Internet Users
Millions
Year
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World’s Cellular SubscribersWorld’s Cellular Subscribers
0
100
200
300
400
500
600
1993 1994 1995 1996 1997 1998 1999 2000 2001
Millions
Year
Digital
Analo g
Source: Ericsson Radio Systems, Inc.
Will providea ubiquitousinfrastructurefor wirelessdata as well
as voice
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Note: surveys consistently underestimategrowth in cellular subscriber base
1994 1996 1998 2000 2002 20040
102030405060708090
100
1994 1996 1998 2000 2002 2004
PCSCellular+PCS
Predicted Continued Growth ofPredicted Continued Growth ofWireless TelephonyWireless Telephony
Millions ofSubscribers
Source: Yankee Group Forecast, 1996
Slow growthin USA in PCS
digital svrcs
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Cellular Phone Growth:Cellular Phone Growth:An International PhenomenomAn International Phenomenom
1990 1995 20000
5
10
15
20
25
30
35
40
45
1990 1995 2000
EuropeUnites StatesJapan
% of main linesthat are mobilephones
Source: Economist, 4 May 1996
By Year 2000:– One in three telephones will be mobile– Mobility becomes a lifestyle
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Telecomms Service Revenue GrowthTelecomms Service Revenue Growth
100
200
300
400
500
600
700
800
900
90 91 92 93 94 95 96
MobileInternational
Source: ITU (the Economist, 13 Sept 97)
Total Revenue 1996: $670 Billion
20% Mobile10% Int’l60% Local10% Other
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Services Most Often RequestedServices Most Often Requested
• Call Forwarding 37%
• Paging 33%• Internet/E-Mail 24%
• Traffic/Weather 15%• Conference Calling 13%• News 3%
DataApplications
Source: CTIA Web PagePeter D. Hart Research Associates, March 1997
After basic wireless telephony service
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Global Markets for Portable ComputersGlobal Markets for Portable Computers
90 91 92 93 94 95 96 97 98 99
2000
0
10
20
30
40
50
60
90 91 92 93 94 95 96 97 98 99
2000
$Bil
Source: Arthur D. Little, Industry Estimatesin the Economist Magazine, 14 May 94
Year
Most rapid growing sector of the PC marketNokia: 20-30% of revenue from data services
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Data Giants vs. Telecomm GiantsData Giants vs. Telecomm Giants
• CISCO– Market Cap: $46 Billion– Annual Sales: $6 Billion
• 3COM/US Robotics– Market Cap: $16.1 Billion– Annual Sales: $5.5 Billion
• Ascend/Cascade– Market Cap: $7.7 Billion– Annual Sales: $1.3 Billion
• Newbridge– Market Cap: $7.4 Billion– Annual Sales: $0.9 Billion
• About $29 Billion inrevenue; growing to $72Billion by 2000
• AT&T– Market Cap: $57 Billion– Annual Sales: $52 Billion
• LUCENT– Market Cap: $48 Billion– Annual Sales: $24 Billion
• GTE– Market Cap: $42.3 Billion– Annual Sales: $21.7 Billion
• Bell Atlantic– Market Cap: $33.3 Billion– Annual Sales: $13.3 Billion
• About $860 Billion inTOTAL revenue; growingto $1272 Billion by 2000
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Presentation OutlinePresentation Outline
• Comparison of Telecomm & Data Comm Industries• Voice-centric versus Data-centric Viewpoint
• Internet versus Telephone Technology• Implications Beyond the Third Generation
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Voice-Centered vs.Voice-Centered vs.Data-Centered?Data-Centered?
• The dramatic rise of the Internet and theWorld Wide Web– Reuters
» 82 million PCs on Internet today» Growing to 286 million by Year 2001
– Internet Demographic Survey (CommerceNet)» 55 million Internet Users in US & Canada» 100 million worldwide
– Telephone Subscribers» 1 billion worldwide» 180 million mobile phone users worldwide
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Voice-Centered vs.Voice-Centered vs.Data-Centered?Data-Centered?
• More than 50% of telecomm traffic in BayArea is already data, not voice– Internet FIND/SVP Survey (Nov/Dec 95)
» 25% of Internet users make fewer long distance calls» 32% watch less television
• Telephone switching infrastructure has beenbrought to its knees– Design metrics based on voice quality, not data
throughput– Design for short duration voice conversations,
not long duration computer sessions
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Voice-Centered vs.Voice-Centered vs.Data-Centered?Data-Centered?
Bell Atlantic
US West
Pacific Bell
SBC
Average Peak-HourLocal Circuit Use
Average ResidentialCall Length
All Circuits Circuits to ISPs All Circuits Circuits to ISPs
5.0
5.0
6.7
6.7
4-5
2-4
3.8
na
43-47
45.0
31.7
52.3
17.7
14
20.8
na
Source: FCC (The Economist, 13 Sept 97)
Network Usage, Minutes
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Will Trend Towards Data-Will Trend Towards Data-Centric Accelerate?Centric Accelerate?
• Sir William Preece, Chief of the British PostalSystem, 1876:
“The Americans may have need of the telephone, butwe do not. We have plenty of messenger boys.”
• Analogy with the Post Office– Telephones have largely replaced the personal letter– Posts used mainly for business-oriented
correspondence: documents (Fed-Express), bills(direct debit/e-commerce), advertising (WWW),delivery of merchandise (UPS)
– Email reduces number of telephone conversations– What will be the effect of the Internet/WWW?
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Will Trend Towards Data-Will Trend Towards Data-Centered Accelerate?Centered Accelerate?
• Many calls to obtain information are already beingreplaced by the WWW– E.g., Ordering Books– E.g., Ordering CDs– E.g., Fyte Trax Service– E.g., Package Tracking– E.g., Booking Flights– and so on
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Efficiencies of InteractionEfficiencies of Interaction
Source: McKinsey (The Economist, 13 Sept 97)
Search: Finding a High-Rate Certificate of DepositTelephoneWWWWWW w/ agent
Co-ordination: Reordering an Inventory ItemMailE-mailEDI
Monitoring: Updating an Equity PortfolioNewspaperWWWWWW w/ agent
25.0
10.0
1.0
Min
-60%
-90%
3.7
1.6
0.3
-57%
-81%
5.1
1.8
0.5
-65%
-72%
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Presentation OutlinePresentation Outline
• Comparison of Telecomm & Data Comm Industries• Voice-centric versus Data-centric Viewpoint
• Internet versus Telephone Technology• Implications Beyond the Third Generation
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What is the Internet?What is the Internet?
“Internet” refers to the global information system that -- (i) islogically linked together by a globally unique addressspace based on the Internet Protocol (IP) or itssubsequent extensions/follow-ons; (ii) is able to supportcommunications using the Transmission ControlProtocol/Internet Protocol (TCP/IP) Suite or itssubsequent extensions/follow-ons, and/or other IP-compatible protocols; and (iii) provides, uses or makesaccessible, either publicly or privately, high level serviceslayered on the communications and related infrastructuredescribed herein.
Federal Networking Council Resolution, 24 October 1995
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Today’s Internet TechnologyToday’s Internet Technology
• Strengths– Intelligence at the end
points; No state in thenetwork;
– Highly decentralized control– Enables operation over very
heterogeneous collection ofaccess technologies; fewassumptions about thenetwork necessary
– Achieves robustcommunications throughpacket switching & store-and-forward routing
– Depends on cooperativeforwarding of packets
• Weaknesses– No differential service– No control mechanisms for
managing bottleneck links– Store-and-forward routing
introduces variable delay inend-to-end performance
– Decentralized controlmakes introduction of newprotocols/functions difficultsince all end nodes must beupgraded
– Lack of truly trustedinfrastructure leads tosecurity problems
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Today’s Telephone NetworkToday’s Telephone Network
• Strengths– Requires no end-point
intelligence; supportsheterogeneous end devices
– Provides excellentperformance for voice
– End-to-end performanceguarantees achievedthrough well-definedsignaling layer to switchingfunction
– True utility functionalitythrough sophisticated andhierarchically arrangedswitches controlled byservice providers
• Weaknesses– Achieves performance by
overallocating resources– 3.4 KHz audio voice band
signal converted to 64 kbpsdigital representation
– Switching designdetermined by statistics ofcall traffic
– Difficult to add new servicesto the so-called “IntelligentNetwork” due to complexfeature interaction
– Expensive approach torobustness
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ATM: The Grand Convergence?ATM: The Grand Convergence?
• Strengths– Virtual circuits with call set-
up to manage scarceresources and achieve QoSguarantees
– Fixed/small size “cells” toenable fast switching
– Sophisticated statisticalmultiplexing mechanisms tomake possible variety oftraffic models
– Integrated services
• Weaknesses– Connection-orientation has
some problems with latencyand robust operation; everycell must follow same path inorder
– ATM unlikely to be a universalend-to-end technology,especially for data traffic inlocal area
– Quaranteed performance end-to-end in heterogeneousenvironments is lost
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Next Generation InternetNext Generation Internet
• “Integrated Services Packet Network (ISPN)”• Ubiquitous support for multipoint-to-multipoint
multicast communications• Built-in support for mobility and mobile route
optimization
• Resource allocation mechanisms based on RSVPsignaling– Performance promises rather than guarantees– Receivers initiate signaling; nice scaling properties– Soft state in the network allows robust recovery to
failure; protocol works around link and switch failures
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Next Generation InternetNext Generation Internet
• Microprocessor performance/software algorithmsnow sufficient for real-time encode/decode ofvideo and audio– Traditional telephony hardware operates at 64 kbps for
PCM coding– Mbone software audio coding at many rates
» 36 kbps ADPCM» 17 kbps GSM» 9 kbps LPC
Adequate video at 28.8 to 128 kbps» Scalable codecs» Layered video
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Next Generation InternetNext Generation Internet
• Real Time Protocol (RTP)– Application Level Framing– End nodes adapt audio/video streaming rates to what
the network can support
• Easy integration of new services like proxies– Hardware/software is not specialized– Easy to integrate distributed applications
• Solve performance problems by adding morebandwidth
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Internet TelephonyInternet Telephony
Local Call Local CallInternet
SF to Frankfurt via Internet Service: $0.28 per min via AT&T Long Distance: $1.25 per min
Analog Voice toPacket Data
Packet Data toAnalog Voice
Source: G-Cubed
Gateway Gateway
Why so Cheap?
Less expensive infrastructureCircumvents government-backed monopoliesExisting long distance tariffs far exceed costsWTO worldwide deregulation
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Internet TelephonyInternet Telephony
• Quality Issues: High Latencies, Dropped Packets– Solutions
» Deployment of private networks» Faster and scalable hardware reduces gateway latency» RSVP + H.323 + Reconstruction of lost packets + Better voice
coding at 8 kbps» VoIP: Voice over Internet Protocol Forum
• Integration of circuit-switched local infrastructurewith packet-switched wide-area infrastructure– Wide-area b/w is a commodity, not true for local access
» 1996-2000: 5X increase in Atlantic/Pacific cable capacity– Many leading telecomms already doing this
» Internet FAX services» Cheap way for RBOCs to get into long distance service
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U.S. Internet Telephony MarketU.S. Internet Telephony Market
1998 1999 2000 2001 2002 2003 20040
0.5
1
1.5
2
2.5
3
1998 1999 2000 2001 2002 2003 2004
SpentSavings
Source: Forrester Research (The Economist, 13 Sept 97)
NewRevenues
CostSavings
4% of U.S. Telephony Revenue
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Presentation OutlinePresentation Outline
• Comparison of Telecomm & Data Comm Industries• Voice-centric versus Data-centric Viewpoint
• Internet versus Telephone Technology• Implications Beyond the Third Generation
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Third GenerationThird GenerationTelecommunications ArchitecturesTelecommunications Architectures
High-tier
Low-tier
Satellite
High Mobility Low MobilityWide Area
Regional Area
Local Area
• FPLMTS/UMTS/IMT-2000– Universal multimedia information access with mobility
spanning residences, businesses, public/pedestrian,mobile/vehicular, national, and global regions
– Low end: 512 kbps; High end: 155 mbps??
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“Mobile BroadbandSystems”
WirelessLocal AreaNetworks
Wireless Access TechnologiesWireless Access Technologies
Mbps
0.01
0.1
1
10
100Wired
Cellular
Cordless
“Universal MobileTelecomms Systems”
(UMTS)
60 GHz100 m range
Office orRoom
Building
Indoors
Stationary Walking
Outdoors
Vehicle
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Beyond Third GenerationBeyond Third Generation
• 1st Generation was analog cellular– e.g., AMPS
• 2nd Generation is digital cellular– e.g., IS-54 (TDMA), IS-95 (CDMA), GSM (TDMA)
• 3rd Generation– Still being defined . . .– Will embrace multiple radio access technologies
suitable for local, wide-area, satellite, etc. and able toachieve higher bandwidth than existing airlinks
– Likely to be based on GSM wireline infrastructure
• 4th Generation– ???
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EIRAUCHLR
Mobile Telecomm NetworkMobile Telecomm Network
BTS
MSCBSC
BSC
VLR
MSC
TSC
MS
Interexchan geNetwork (IXC)
Local ExchNetwork
Local LoopRBOCs
TransitSwitching
Center
AT&TMCI
SprintWorldCom
. . .
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EIRAUCHLR
Data Over Analog CellularData Over Analog Cellular
MSCBSC
VLR
Interexchan geNetwork (IXC)
Local ExchNet (LEC)
TSC
Digital -- Analog (modem) --Digital (IXC) -- Analog (local loop) --
Digital (modem)Circuit Switched
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EIRAUCHLR
Data Over Digital CellularData Over Digital Cellular
MSCBSC
VLR
Interexchan geNetwork (IXC)
Local ExchNet (LEC)
TSC
IWFDigital -- Analog (modem) --
Digital (IXC) -- Analog (local loop) --Digital (modem)Circuit Switched
9.6 kbps to100+ kbps
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Internet
EIRAUCHLR
Internet ArchitectureInternet Architecture
MSCBSC
VLR
Local ExchNet (LEC)
GW
Digital -- Analog -- DigitalPacket Switched
Local Circuit Switched
ISDN: digital tothe home
ISP
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Internet
EIRAUCHLR
Internet ArchitectureInternet Architecture
MSCBSC
VLR
CorporateIntranetwork
GW
Fully Digital/Packet Switched
GW
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NextGeneration
Internet
Internet ArchitectureInternet Architecture
BSC
EIRAUCHLRVLR
CorporateIntranetwork
GW GW
SmartCommunicator
MSC
ProxyServers
BS
Digital CellularLink Layer
WLAN/WPBXLink Layer
HAFA
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Summary and ConclusionsSummary and Conclusions• Accelerating importance of data access in cellular
telecommunications infrastructures: data willdominate voice applications
• Internet’s emerging capabilities for real-timetraffic, multipoint communications, broadcast-based information dissemination
• Secret of Internet’s success– Intelligence at the end points– Simple and inexpensive infrastructure components– Gain performance through bandwidth
• Economies of scale favor the Internet– Cause for a dramatic re-thinking of telecomms
infrastructure beyond the 3rd Generation