Integrated Broadband Networks

1
Integrated Broadband Networks
EE420.594 Fall 2005

• Chapter 1
• Introduction
• Byeong Gi Lee
• Seoul National University

2
Contents

• Main Driving Forces for Broadband Development
• IP, ATM, Optical, Wireless
• History and Recent Developments
• Internet and TCP/IP
• ATM Technology
• SDH/SONET
• WDM/Optics
• Recent Developments
• Organization of the Course

3
Technological Driving Forces

• IP technology
• WWW/Internet and TCP/IP network protocol
• Originally, e-mail was the killer application
• The real explosion in Internet growth occurred
  with the appearance of the WWW
• TCP/IP technology may now be the answer to the
  Holy Grail of Networking
• A single unifying communications protocol for
  everywhere/everything

4
Technological Driving Forces

• ATM technology
• Developed and deployed by the telephone service
  providers
• Mature, stable, flexible, with numerous advanced
  features (Most frequently discussed advantage of
  ATM is its built-in support for QoS)
• Has not been widely accepted in the major data
  markets
• A firm basis for the integration of PSTN networks
  and the data networks
• Provides a theoretical foundation for integrated
  QoS network technology (like OSI 7 layer
  architecture)

5
Technological Driving Forces

• Optical technology (3)
• Made possible by SDH/SONET and WDM/Optics
• First stage based on SDH/SONET
• Next stage all-optical networks based on WDM
  technology
• All the new traffic takes and will take more
  bandwidth
• Copper wires are fundamentally limited
• The basis for all the future bandwidth is optics

6
Technological Driving Forces

• Wireless technology
• Mobile wireless services is preferred due to its
  wireless, mobile, and private nature.
• Mobile communication has been increasing even
  faster than the Internet !
• Networks originally optimized for voice, not for
  carrying data, but data capacity has grown to
  Mbps range.
• Wireless communications technology has been
  advancing to increase the data capacity rapidly.
• Costs would be cut and data service would be
  easier by using IP technology as the base
  infrastructure.

7
History and Recent Developments

• Internet and TCP/IP
• ATM Technology
• SDH/SONET
• WDM/Optics
• Recent Developments

8
Internet and TCP/IP

• Store-and-forward packet switching, 1961
• Efficiently utilized available transmission
  facilities
• Afforded reliability by the use of retransmission
  mechanisms
• mesh topology more robust to military attacks

9
Internet and TCP/IP

• ARPANet, 1966, 1969
• Connected four universities
• To share expensive heterogeneous computer
  facilities among researchers
• developed basic ideas and applications of
  internet (packet switching, decentralized
  routing, flow control, Telnet, FTP)

10
Internet and TCP/IP

• Birth of the Internet
• Initiated by ARPAnet 1983, taken by NSF Net 1986
• The internet A network of networks
• To connect ARPAnet and other networks
• Concept of a gateway between networks
• Key decisions, which still drives the Internet
• Decentralized administration
• Designed for scaling
• Bare-bones assumptions by IP

11
Internet and TCP/IP

• Growth of the Internet
• 1980s roughly 10 ARPAnet based networks
• NFSnet
• Took over Internet 1986, based on Federal Funding
• Connected universities, research /non-profit
  organizations
• Diffused into commercial and international
  sectors
• Opened Internet to commercial traffic, 1992
• Federal funding withdrawn in 1995

12
Internet and TCP/IP

• Basic TCP/IP protocols (late 1970)
• The preferred networking protocol(In 1978, U.S.
  government)
• WWW(World Wide Web)
• First designed and built by Tim Berners-Lee at
  CERN, as a way for physicists to share
  information
• URL (universal resource locator)
• HTML (hyper-text markup language)
• HTTP (hyper-text transfer protocol)

13
Internet and TCP/IP

• WWW (World Wide Web) (contd)
• Concept of a hypertext machine traced back to
  Vannebur Bush, 1950s
• Mosaic browser -- a graphic interface
• Netscape becomes first big Internet success
• Amazon and all the other dot.coms followed
• The Internet Economy, The New Economy

14
ATM Technology

• ISDN (ITU-T, late 1970)
• Integrate voice, image and data signals in one
  format
• DS-0 rate (64kbps) based
• Basic Rate Access (BRA) at 144kbps (2BD),
  Primary Rate Access (PRA) at DS1/DS1E
  rate(1.544/2.048Mbps)
• Network Termination (NT), Terminal Equipment
  (TE), S/T Reference Points
• Standardized by ITU-T in 1984, 1988

15
ATM Technology

• B-ISDN (mid 1980)
• Intended to expand the ISDN standards to
  accommodate broadband services such as
  videophones and teleconferences
• Strongly influenced by the SDH/SONET and ATDM
• Fixed-sized packet based integration
• SDH/SONET rate (155.52 Mbps) based

16
ATM Technology

• ATM
• Adopts asynchronous transfer mode (ATM)
• Possesses the capability to integrate all
  telephone and data networks
• Standardized by ITU-T in 1988, 1992
• Influenced by SDH/SONET, ATDM(proposed by W.W.
  Chu at Bell Labs in 1968) and DTDM(proposed by
  Sanghoon Lee at Bellcore in 1988)
• Computer vendors and telecommunication service
  provider organized the ATM Forum in 1991

17
ATM Technology

• ATM (contd)
• Integration of Broadband Services
• Demand for high-speed data, image/video services
  foreseen
• Bandwidth of ISDN overly limited
• Optical technology getting matured
• SDH/SONET standard getting available
• Means to integrate diverse set of broadband
  services needed

18
ATM Technology

• ATM (contd)
• Background Switching Technology
• Asynchronous Time Division Mux (ATDM)
• Added headers to the slots for efficient
  switching
• Spider
• concept of virtual circuits, fixed sized packets
• Datakit
• voice and data in one format, statistical
  multiplexing
• Dynamic Time Division Multiplex (DTDM)

19
ATM Technology

• ATM (contd)
• BISDN and ATM Network
• BISDN standardized under ISDN concept
• ATM adopted as the means of service integration,
  transmission and switching in BISDN
• fixed size packet, virtual circuit, statistical
  muxing, scalable bandwidths
• ATM Forum formed among computer companies
• real driving force of many ATM standards.
• specs for signaling, physical layer, interworking

20
ATM Technology

• ATM (contd)
• Advantages of ATM
• Packet switching technology
• Scalable large bandwidth
• Unlimited bandwidth granularity compared to the
  traditional circuit switches
• Support of voice, video and data

21
SDH/SONET

• Metrobus (Bell labs, 1982)
• objective
• Develop an optimal communication system that
  takes full advantage of optical communications
  and the evolutions in communication networks,
  device technology and service growth
• The point-to-multipoint optical network
• Initial conception of Metrobus made by Jan Spalink

22
SDH/SONET

• Metrobus (Bell labs, 1982) (contd)
• One-step multiplexing
• Enables a direct multiplexing of DS-1 signals at
  1.544 Mbps to the 150 Mbps internal standard
  signal without passing intermediate DS-2 and DS-3
  signals
• Establishment of 146.432Mbps as the internal
  signal standard
• Enables accommodating all existing North America
  and European hierarchical tributaries
• Enables to take full advantages of the supporting
  technologies

23
SDH/SONET

• Metrobus (Bell labs, 1982) (contd)
• Internally synchronous operation
• Beginning of the synchronous communication
  network
• Visibility of DS-0(at 64 kbps) at the exterior
  frame level
• Direct consequence of the constructing a
  125-?s-based frame structure
• Simultaneous accommodation of tributaries by
  controlling the number of containers
• Maximum utilization of overhead

24
SDH/SONET

• SONET (Bellcore, 1984)
• Synchronous Optical Network
• Initially targeted at the goal of midspan meet
• Little progress was made in its standardization
  during the early stage
• Momentum gained after the announcement of
  Metrobus in 1985
• The concepts of layered system structure and
  pointer-based synchronization was proposed by J,
  Ellson
• Modified in frame structure and bit rate form
  50.688 Mbps to 49.92 Mbps

25
SDH/SONET

• SONET (Bellcore, 1984) (contd)
• Got finalized at the rate of 51.84 Mbps ( which
  is a third of the rate 155.52 Mbps ) in 1988

26
SDH/SONET

• Synchronous Digital Hierarchy (CCITT,1986)
• To be used for the network node interface(NII)
  independently of user-network interface(UNI)
• The 9B x 270 structure at the 155.520 Mbps rate
  was chosen as the STM-1 standard in 1988.
• Fundamental to all SDH, SONET and ATM
• Kicked back the SONET standardization with the
  restructuring of the STS-1 signal to the rate of
  51.84 Mbps

27
SDH/SONET

• SDH (CCITT,1986) (contd)
• Features derived from SONET
• Layered system structure
• Systematic overhead organization
• Synchronization via pointers
• Establishment of global networking

28
SDH/SONET

• SDH (CCITT,1986) (contd)
• Features derived from Metrobus
• Point-to-multipoint optical network
• Internally synchronous operation
• Visibility use of DS-0 through a 125-?s time unit
• One-step multiplexing
• Accommodation of muti-rate signals by controlling
  the number containers
• Establishing 150 Mbps as the internal signal
  standard
• Enhancing the network adaptability and
  reliability through versatile use of overheads

29
WDM/Optics

• Optical transmission system
• Initially used for long-distance transmission
• Concept of fiber-optic transmission, 1950s
• Become practical with 20dB/km loss, 1970s
• High-speed optical transmission possible with
  low-loss fibers and semiconductor laser diodes,
  1980s
• Later migrated into network-oriented synchronous
  transmission
• SDH/SONET systems, 1990s

30
WDM/Optics

• First-generation optical network
• The SONET and SDH optical system
• Based on the point-to-multipoint network
• Transmission and switching processes still done
  in electrical domain.
• Second-generation optical network
• The wavelength-division multiplexing(WDM) network
• Meets the demands for bandwidth increase
• Combines multiple optical signal in different
  wavelengths into one optical signal

31
WDM/Optics

• Third-generation optical network
• Switching and routing processes arranged to take
  place in optical domain.
• All-optical network

32
WDM/Optics

• All optical networks
• Gained interest in the local network sector in
  the mid-1980s
• Broadcast and select based networks
• Tunable laser
• Passive optical coupler
• Lambdanet, Rainbow, Starnet,
• Wavelength routing networks
• Optical ADM(OADM)
• Optical cross-connects(OXC)

33
WDM/Optics

• All optical networks (contd)
• Under rapid evolution
• Optical switches, logic devices, storage devices,
  etc. being developed
• Advanced optical transmission products being
  manufactured
• Advanced optical networking products expected in
  the near future

34
Recent Developments Human Factors

• Need for bandwidth
• WWW has been the basis for the growth and spread
  of the Internet.
• More people want connection to the Internet.
• More applications are being developed audio,
  graphics, video, i.e. multimedia
• All these require more and more bandwidth

35
Recent Developments Human Factors

• Need for QoS (Quality of Service)
• Many of the new applications require QoS
  guarantees
• VoIP needs some sort of minimal bandwidth and
  delay guarantees.
• Video also needs some bandwidth and delay
  guarantees.
• Time-critical data transactions such as stock
  market buy/sell orders

36
Recent Developments Human Factors

• Need for QoS (Quality of Service) (contd)
• ISPs and network operators need to find ways of
  making money by other than flat rates
• Flat rates are limited in revenue generation
• Giving better services to paying customers is one
  way of increasing revenue
• VPN(Virtual Private Networks) for corporate users
  is another revenue source

37
Recent Developments Human Factors

• Personalization
• First experience from personal computers
• Then wireless mobile communication has led it.
• Why do you need a wire to stay connected?
• Mobile communication is increasing even faster
  than the Internet.
• Services such as real-time stock quotes, web
  surfing, e-mail are becoming available

38
Recent Developments Human Factors

• Personalization (contd)
• Wireless network evolution in progress
• Current wireless infrastructure is based on
  leased lines and expensive ubiquitous networks.
• Networks are optimized for voice, not for
  carrying data, but growth will be in data.
• Costs would be cut and data service would be
  easier by using IP technology as the base
  infrastructure.
• Personalization continues in DMB and WiBro.

39
Recent Developments Human Factors

• Ubiquity in Web Access
• The web explosion
• Internet Cafes
• WAP phones (phone.com), I-Mode (NTT Docomo)
• Web accessible everything!
• E-Commerce the dot.coms
• Amazon.com, eBay.com, E-trade, Yahoo!
• NASDAQ

40
Recent Developments Human Factors

• Multimedia
• VoIP technology
• cheap long distance to feature rich phone
• Mutlimedia conferencing
• Microsoft Netmeeting, H.323 based solution
• MP3
• revolution in the music industry
• Movies
• Streaming technologies developing.

41
Recent Developments Driving Technologies

• The Web and the Internet
• TCP/IP was in search of a killer app
• E-mail was the original killer app
• The Web was the real ignition fuel
• TCP/IP technology may now be the answer to the
  Holy Grail of Networking
• A single unifying communications protocol for
  everywhere/everything

42
Recent Developments Driving Technologies

• Optical Communications and Networks
• All the new traffic takes and will take more
  bandwidth
• Copper wires are fundamentally limited
• The basis for all the future bandwidth is optics
• Present SDH/SONET systems
• Future WDM/optical systems

43
Recent Developments Driving Technologies

• Mobile Wireless Communications
• Preferred due to its wireless, mobile, and
  private nature.
• Originally optimized for voice, but data carrying
  capacity grown rapidly to Mbps range.
• Other electronic functions expedited the cellular
  phone based device integration
• Costs would be cut and data rate would hike by
  using IP technology as the base infrastructure.

44
Recent Developments Driving Technologies

• Integration/Convergence of Services
• Integration initiated by ISDN/BISDN
• ATM networks introduced first complete means for
  integration
• Most importantly built-in support for QOS
• Evolved into wireline and wireless integration
  (WiFi, WiMax, WiBro)
• Convergence diffused to communications and
  broadcasting (DMB)

45
Organization of the Course 3 Parts

• Part I. Six Functional Components for
  Communications Networks
• Part II. Four Technological Components of
• Broadband Networks
• Part III. Interactions and Integration
• of Broadband Networks

46
Part I. Functional Components

• There are six functional components that form a
  frame for discussion and comparison of basic
  broadband network technologies.
• layering
• multiplexing and switching
• routing (or add/drop and cross-connect)
• traffic management
• network control and management
• Quality of service (QoS) issue

47
Six Communication Functional Components
48
Part II. Technological Components (1)

• Broadband Technological Components
• Broadband Subscriber Networks (topics of the
  course Broadband Access Networks
• xDSL, HFC, FTTx
• Synchronous transmission technology - SDH/SONET
• Asynchronous transfer technology - ATM
• TCP/IP protocol suite - Internet
• Optical transmission and networking WDM/optics
• Broadband Video Services and Technology (time
  permitting)
• Mobile wireless communications technologies
  (BAN)

49
Networks, Services, and Technologies for
Broadband Telecommunications
TCP/IP and Broadband Data Services
Broadband Multimedia Services and Technology
BISDN and ATM Technology
Wireless Communications and Access Technology
Synchronous Digital Transmission
Broadband Subscriber Network
Optical Technology and Network
50
Part II. Technological Components (2)

• Four Infrastructural Network Components
• TCP/IP, ATM, SDH/SONET, WDM/optics
• Each network component could be a total solution
  to the problems of networking
• Each has its own solutions for each facet of the
  principles to be discussed in Part II
• The four components may be integrated together
  hierarchically (Part III)

51
Four Infrastructural Network Components
Internet
ATM
SDH/SONET
WDM/Optics
52
Part III. Interactions Integration

• Examine the interactions among the 4 basic
  network technologies in terms of the 6 functional
  components
• There are various integration approaches
• IP vs. ATM
• IP vs. SDH/SONET
• IP vs. WDM
• ATM vs. WDM
• SDH/SONET vs. WDM

53
Interactions Integration of Four Network
Components
Internet
ATM
Discussed in terms of 6 functional components
Interactions Integrations of 4 technological
Components
SDH/SONET
Optical
54
Supplementary Slides
55
Evolution of Communication Technologies and
Networks

• Communications and Networks
• Transmission Technology
• Switching Technology
• Signaling Technology
• Packet Communication
• Integrated Services Networks

56
Communications and Networks

• Trunk network, subscriber network, local area
  network
• Public network (PSTN, PSDN), private network
• Nodesswitching, linkstransmission,
  connectionsignaling
• Voice communications, packet communications
• Integrated services networks (ISDN, BISDN)

57
Transmission Technology (1)

• Transfers user information and control signals
• Transmitting terminal, medium, receiving terminal
• Analog, digital, integrated
• A/D conversion, modulation, multiplexing, coding,
  E/O or E/M conversion
• Twisted-pair, coax, fixed radio, satellite,
  optical, mobile radio

58
Block Diagram of Transmission Systems
(unidirectional)
Transmission facility
Transmitting terminal
Medium
Intermediate device
Receiving terminal
Medium
59
Transmission Technology (2)

• Developmental Process
• Telephone 1876,
• FDM system 1925,
• fixed radio system 1927,
• PCM (TDM) system 1962,
• satellite system 1965,
• digital radio system 1969,
• optical system 1979,
• SDH/SONET standard 1988,
• mobile phone system 1990s,
• CDMA system 1996

60
Switching Technology (1)

• Establishes connections among users
• Manual, mechanical, electronic
• Switching fabric, subscriber and trunk
  interfaces, switch control, OAM and control
  network interfaces
• Space division /time division, wired-logic
  control /store program control
• Analog switch, digital switch

61
Block Diagram of Switching Systems
62
Switching Technology (2)

• Developmental Process
• automatic switching conception 1879,
• step-by-step switch 1900s,
• crossbar switch 1938,
• electronic switch 1965,
• time-division digital switch 1976,
• ATM switch 1990s,
• MPLS 2000s

63
Signaling Technology

• Process of transferring information for the
  control of communication set up
• Surveillance, addressing, information
• Subscriber network signaling, trunk signaling
• Channel associated (in-band/out-of-band)
  signaling, common channel signaling (CCS)
• Intelligent Network (IN) -- network flexibility
  and service intelligence

64
Signaling Systems
Channel-Associated Signaling
Trunk
Signaling
Signaling
Signaling
Signaling
Switching node
Switching node
Signaling
Signaling
Common-Channel Signaling (CCS)
Trunk
Switching node
Switching node
Signaling equipment
Signaling equipment
CCS
CCS
65
Packet Communications (1)

• Circuit-switched vs. packet-switched
• Consecutive bit stream vs. intermittent packet
  flow
• Connection setup vs. connectionless
• Computer data, private local networks
• Protocol, OS (Open System Interconnection) model
• Layered architecture

66
Layered Architecture for Packet Communication
67
Packet Communications (2)

• Developmental Process
• Large scale computers 1960s,
• ARPANET 1969,
• Systems Network Architecture (SNA) 1974, DECNET
  1975,
• ITU-Ts X.25 1974,
• TCP/IP suite 1970s (1978),
• OSI Reference Model 1980s (1983),
• Internet/NSFNET 1983/86,
• 10M Ethernet 1985, Fast Ethernet (100Mbps),
  Gigibit Ethernet
• 100M FDDI 1986
• Wireless LAN (WiFi), MAN (WiMax), WiBro, 2000s

68
Integrated Services Networks (1)

• Integrated Services Digital Network (ISDN)
• Circuit-mode based integration of voice, data and
  video services
• DS-0 rate (64kbps) based
• Basic Rate Access (BRA) at 144kbps (2BD),
  Primary Rate Access (PRA) at DS1/DS1E rate
• Network Termination (NT), Terminal Equipment
  (TE), S/T Reference Points
• ITU-T Standardized 1984, 1988

69
Basic Architecture Model of ISDN
70
Integrated Services Networks (2)

• Broadband ISDN (BISDN)
• Fixed-sized packet based integration
• SDH/SONET rate (155.52 Mbps) based
• Integrates all type of broadband services
• Adopts asynchronous transfer mode (ATM)
• Possesses the capability to integrate all
  telephone and data networks
• ITU-T standardized 1988, 1992

71
Architecture of BISDN
PSTN
ATM SW
IWU
PSDN
HFC CATV net
SDH/SONET
ATM SW
ATM SW
PCN
B-NT
B-NT
LAN/MAN
TE
TA
B-TE

PBX
72
Trends of Evolution

• Digitalization
• Expansion/explosion of data services
• Integration of services and networks
• Intelligent services and networks
• Personalized services
• Mobilized networks
• Broad bandwidth
• Service integration / convergence

73
Evolution of Communication Networks
Private data networks
High-speed LAN,MAN
LAN
Gigabit Network
WiBro
Public data networks
BISDN
PSDN
NISDN
Public telephone network
Integrated Broadband Network
FTTC, FTTH
PSTN
ADSL, VDSL
HFC
(Broadband Convergence Network)
Broadcasting networks
MMDS, LMDS
CATV Net
DMB
Wireless access networks
Cellular, PCS
UMTS, IMT
Wireless Net
74
Technological Support

• Optical technology (laser, fiber, amplifier)
• Electronic technology (processing, memory)
• Communication technology (transmission,
  switching/routing, packet processing)
• Display technology (HDTV, LCD/PDP)
• Mobile wireless technology (cellular, modem)
• Multimedia technology (audio/video codec)
• Standards support (ATM, TCP/IP, MPEG, 3GPP, WiBro)

75
Base Technologies for Broadband
Telecommunication
MPEG-2 (10M)
LCD, PDP
Single-mode fiber
Coherent
GaAs
MPEG (1.5M)
Flat panel
OFDM (IM/DD)
Bipolar ECL
Multimode fiber
H.261 (n x 64kbps)
Color
WDM (IM/DD)
CMOS
Coax cable
JPEG (Still picture)
B/W
TDM (IM/DD)
Si-bipolar
Copper-wire
Video signal processing
Display technology
Transmission medium
Optical transmission
Device technology
Gb Net
Optical
OFDMA 4G
DQDB MAN
ATM
SDH/SONET
ATM
WCDMA 3G
FDDI LAN
Digital
PDH
Digital/ Packet
Digital 2G (GSM, CDMA)
LAN (Ethernet)
Analog
Analog
Analog
Analog 1G
High-speed data network
Switching technology
Transmission hierarchy
Communication modes
Wireless technology
76
Key Technologies for Broadband Networks and
Services

• Subscriber broadband access technology
• Broadband transmission, switching/routing
• ATM communications technology
• High-speed packet communications
• Broadband video and multimedia services
• Optical devices and communications
• Mobile wireless communications