Optinen verkkotekniikka
TKK, 9. 4. 2002
S-38.164 Laajakaistainen välitystekniikka
kevät 2002
Jaakko Aarnio
Nokia Research Center
jaakko.aarnio@nokia.com
S-38.164 Laajakaistainen välitystekniikka - K-2002
Tutorial, optics and networking_JA.PPT / 9.4.2002 / JA page:
Yhteenveto
Internet- ja multimedialiikenteen huima kasvu on johtaa siihen, että dataliikenne syrjäyttää
perinteisen puhelinliikenteen hallitsevan roolin tietoliikenneverkojen liketoiminnassa.
Kaistanleveysvaatimukset tulevat sen myötä kasvamaan suuresti lähitulevaisuudessa syntyy akuutti tarve paljon suurempiin siirto ja kytkentänopeuksiin kuin mitä nykyiset ATMja SDH-verkot pystyvät tarjoamaan. Se edellyttää mm. uusien optisten järjestelmien
käyttöönottoa verkkojen infrastruktuurissa.
Yksimuotokuidun kapasiteetin voidaan arvioida olevan noin 50 terabittiä sekunnissa (Tbps),
joka on noin neljä kertaluokkaa suurempi kuin elektroniikan nopeus. Kuidun kapasiteettia
pyritään hyödyntämään yhä paremmilla transmissiotekniikoilla, optisella kytkentäisyydellä
ja kuidun alkuinvestointien jakamisella monipalvelu-tilaajaverkoissa.
Aallonpituusmultipleksointi (wavelength division multiplexing, WDM) on yksi keino
hyödyntää kuidun kapasiteettia, missä loppukäyttäjän laitteet toimivat vain sähköisellä
nopeudella, mutta useat eri loppukäyttäjien WDM-kanavat voidaan multipleksoida samaan
kuituun. Lähitulevaisuudessa odotetaan asteittaista siirtymistä optisten ratkaisujen käyttöön
myös tilaajaverkoissa (kiinteät ja langattomat verkkoratkaisut).
Tämä esitys on katsaus optisten ratkaisujen kehityksestä data- ja tietoliikenneverkoissa.
"IST-road map for optics communications, 2001" on liitetty myös mukaan.
S-38.164 Laajakaistainen välitystekniikka - K-2002
Tutorial, optics and networking_JA.PPT / 9.4.2002 / JA page:
Content
• Need for optical networking
• Basic technologies
• Optical networking in
–
–
core/metro solutions
access for fixed and wireless solutions
• Technology roadmap
• Standardization
S-38.164 Laajakaistainen välitystekniikka - K-2002
Tutorial, optics and networking_JA.PPT / 9.4.2002 / JA page:
Need for optical networking
• User and service requirements
• Increasing traffic volumes
• see also internet indicators:
http://www.internetindicators.com/
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Market evolution for Fiber Networks
Cumulative
Market
size
Access wave
Metro wave
Core wave
1990
1995
2000
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Tutorial, optics and networking_JA.PPT / 9.4.2002 / JA page:
2005
2010
Internet economy and carriers' earnings
Global internet commerce revenue since 1998
>216 Billion US Dollars (March 26, 2001)
ref: http://www.internetindicators.com/facts.html
• The Internet Infrastructure Indicator
• The Internet Applications Infrastructure Indicator
• The Internet Intermediary Indicator
• The Internet Commerce Indicator
Carriers earn best on voice:
1200
1000
800
data transmission
voice transmission
600
400
200
2009
2008
2007
2006
2005
2004
2003
2002
2001
2000
0
1999
Revenues in Billions
of US dollars
1400
Source: Datamonitor 1999
S-38.164 Laajakaistainen välitystekniikka - K-2002
Tutorial, optics and networking_JA.PPT / 9.4.2002 / JA page:
User and Service Requirements
64kb/s100kb/s 1Mb/s
Response time (ms)
10000
1000
10 Mb/s
100Mb/s
1Gb/s
D
F
G
E
100
C
A
A. POTS
B. Videoconferencing (low quality)
C. Videoconferencing (high quality)
D. Teleworking
E. Telelearning
F. Information exchange including
and retrieval Internet
G. Entertainment
B
10
1
102
103
104
105
106
107
108
109
Information content (bits)
Source: Heinrich Hertz Institute
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Tutorial, optics and networking_JA.PPT / 9.4.2002 / JA page:
Evolution of Transport Technology
Ref: D.T. Neilson & al.: 35,8Tbps (320 Gbps, 112*112 ports)
MOEMS based OXC demonstrated at OFC 2000, PD12
WDM
SDH
PDH
Historical traffic increase by a factor of 30-60 at each step.
100000
10000
1000
100
10
1
0.1
0.01
Teleph
Mbit/s
(source: ACTS/Horizon)
Some Basics (Fiber attenuation)
By elimination of water peak attenuation, total
usable bandwidth in fiber has been increased to
some 45 THz (+50%), including L-band (1560-1600
nm) as 4th window (not shown in Fig.).
30 THz Usable
Bandwidth
Loss
100 nm 150 nm
800
1000
1200
1400
1600
1800
Wavelength (nm)
Ref:Lucent Tech., Allwave fiber
S-38.164 Laajakaistainen välitystekniikka - K-2002
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Basic technologies
• Fiber capacity
• Optical multiplexing
–
Wavelength Division Multiplexing
• Evolution of capacity & cost
S-38.164 Laajakaistainen välitystekniikka - K-2002
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Dense vs. Coarse WDM
transmission
Ref: J. Campbell, Coarse WDM makes waves in Metro/access markets, Laser Focus World, Nov 2000
S-38.164 Laajakaistainen välitystekniikka - K-2002
Tutorial, optics and networking_JA.PPT / 9.4.2002 / JA page:
Dense vs. Coarse WDM transmission
• CWDM devices available
• light sources not yet available
due to lack of standard
S-38.164 Laajakaistainen välitystekniikka - K-2002
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Wavelength Allocation
192.100 THz (1560.61 nm) as
reference wavelength, 100 GHz
grid.
• Wavelength Located in flat gain
region of Erbium-Doped Fiber
Amplifier (EDFA), the flat gain
region depended on the saturation
level of EDFA, etc.
• New developments in S-band (Thullium
Doped FAs, 1450-1500 nm) to broaden
the wavelength region at short wavelength
region.
• Wavelength Spacing depend on
the techonologies of laser, optical
multiplexer and demultiplexer, etc.
• L-band doubles the gain bandwidth
of an optical amplifier.
S-38.164 Laajakaistainen välitystekniikka - K-2002
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1
0
8
6
4
2
0
2
4
6
8
1
0
1
2
1
4
1
6
1
8
2
0
2
2
2
4
2
6
2
8
3
0
3
2
3
4
3
6
3
8
4
0
4
2
4
4
4
6
4
8
5
0
1
5
2
0
SignalndASELevl(dBm)
• ITU-T Standards:
E
D
F
A
a
t
f
i
b
e
r
l
e
n
g
t
h
=
2
6
m
EDFA Spectrum
1
5
4
0
1
5
6
0
W
a
v
e
l
e
n
t
h
(
n
m
)
~25 nm
1
5
8
0
Cost & Capacity evolution
Submarine Networks
Nb of tel. circuits
10 000 000
Cost/circuit
(US$/km)
From 1956 to 1998 :
Capacity x 7200
Cost/circuit ÷ 10000
1 000 000
Cost per
circuit
100 000
TAT-1
10 000
10000
TAT-2
TAT-4
1000
TAT-3
TAT-7
TAT-5
1000
TAT-6
100
TAT-8
TAT-9
100
TAT-12/13
10
Gemini
1
1860
1950
1960
1970
S-38.164 Laajakaistainen välitystekniikka - K-2002
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1980
1990
2000
2010
10
1
Cost evolution of 600 km 2.5 Gb/s
circuits
Year
Pre 1994
1995
1995
1996
1996
1997
1998
Cost/2.5 Gb/s
$K
Capacity
(Gb/s)
Trans. Rate
(Gb/s)
Nb. 
750
525
199
144
117
97
?
2.5
2.5
10
20
40
100
400
2.5
2.5
2.5
2.5
2.5
2.5
10
1
1
4
8
16
40
40
from Ryan Hankin Kent
 Drastic reduction of cost due to WDM
(~ 10 x over 4 years)
S-38.164 Laajakaistainen välitystekniikka - K-2002
Tutorial, optics and networking_JA.PPT / 9.4.2002 / JA page:
Source : Alcatel
Key technology trends
• Multimedia and other services requiring more bandwidth lead to a strong
increase in traffic (about 35% annual growth for data and 10% for voice in
core transport).
• Optical communication technologies will have direct impact on future
datacommunication network infrastructure to efficiently and economically
support the wide diversity of present and future applications and services.
• Optical networks have huge bandwidth 10 THz available with many
beneficial features (e.g. cost-efficiency, survivability, scaleability,
reconfigurability, transparency).
–
New networking solutions are enabled by new developments in component
technologies (e.g. wavelength conversion, optical switching components,
technical solutions for signal monitoring in optical layers).
–
Terabit switching platform development may combine IP, ATM, Gig-E,
SDH/SONET, and wavelength switching.
S-38.164 Laajakaistainen välitystekniikka - K-2002
Tutorial, optics and networking_JA.PPT / 9.4.2002 / JA page:
Optical networking
•
•
•
•
WDM network evolution
Evolution in access and core
Optical networking as part of communication networks
Simplification of protocol stacks - Optical Internetworking
S-38.164 Laajakaistainen välitystekniikka - K-2002
Tutorial, optics and networking_JA.PPT / 9.4.2002 / JA page:
Scenario for the WDM deployment
in the transport network
Technology evolution
Interconnected rings
and mesh topologies
OXC
OXC
OXC
OXC
OXC
WDM rings with
full connectivity
OADM
OADM
OADM
OADM
OADM
WDM rings with
node addressing
OADM
OADM
OADM
OADM
OADM
WDM transmission with add/drop
OADM
OADM
WDM transmission
1996
2000
2004
2008
Ref: ACTS/Horizon
S-38.164 Laajakaistainen välitystekniikka - K-2002
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Optical cross connect (OXC)
- principle of operation
• Optoelectronic crossconnects
available at 512x512 port counts
• Transparent design based on
MOEMS technology:
Optical space switch
WDM
O/E/O conversion
Opaque
‘f’ conversion
optical bypassing
OXC
Transparent
Note: OAM signaling is considered separately.
S-38.164 Laajakaistainen välitystekniikka - K-2002
Tutorial, optics and networking_JA.PPT / 9.4.2002 / JA page:
Ref: Agilent technology, OFC 2000
Is telecom still going to rule the backbone
and regional environment ?
data +35%/yr
in US
TIME
S-38.164 Laajakaistainen välitystekniikka - K-2002
Tutorial, optics and networking_JA.PPT / 9.4.2002 / JA page:
voice +10%/yr
Direct optical access
(SDH, ATM, WDM, IP, other)
Network Evolution Options
(10 Mb/s)
ACCESS
open optical
interface
(50 Mb/s)
Radio/
Mobile
Copper
+ ADSL
(100 Mb/s)
VDSL FTTH
PON
(ATM) (Super)
PON
(ATM)
IP:ATM
SDH
TRANSPORT
SDH: ADM
Packet OADM
WDM
32 x 10 Gb/s
SDH: DXC
OADM
Photonic
Transport Layer
Packet OXC
WDM
OXC
1 Tb/s WDM
HORIZON Project - ACTS
May 1998
Evolution in Layering
IP
ATM
SDH
SDH
ATM
IP
Other
Open Optical Interface
Optical layer (e.g.WDM)
(source: ACTS/Horizon)
S-38.164 Laajakaistainen välitystekniikka - K-2002
Tutorial, optics and networking_JA.PPT / 9.4.2002 / JA page:
Issues of optical networking
–Transparency in optical networks
–Interoperability and Interworking
–Network and equipment architectures
–Network management, monitoring and protection
–Passive and active components
–Network planning, design and performance evaluation
–Different levels of optical regeneration and wavelength
conversion
S-38.164 Laajakaistainen välitystekniikka - K-2002
Tutorial, optics and networking_JA.PPT / 9.4.2002 / JA page:
State of the art
Commercial
1995
2.5 Gb
Line Bit Rate
Total FibreCapacity 20-40 Gb
# WDM Channels
Channel Spacing
Opt. Transparent
8
200 GHz
120 km
Network
Architecture
pt-pt
WDM
Subsystems
OA
100 Gb
DFB laser
2000
2005
2.5 Gb
10 Gb
400 Gb
(2.5 Gb)
10 Gb
16-32
64
100 GHz 50 GHz
600 km
3-5000 km
fixed
OADM
Services
POTS
64 Kb
POTS
Internet,
Videophony,
e-commerce
AOWC
40 Gbit/s ICs
cable modem
ADSL
2-8 Mb
Teleworking, Lan-Lan,
fast Internet, video,
games,telelearning...
Technology road map, HORIZON Project - ACTS
Opt.
Packet
Gb routers
with QoS
small meshed, flexible
WDM networks
flexible OADM
small OXC
selectable/ tuneable lasers
ISDN
128 Kb, 2 Mb
10 Gb
40 Gb
>1 Tb
Gb routers 5000+ km
low cost optical transceivers
User Access
Bit Rate
2002
2010
128
25 GHz
fixed
flexible OADM/
OADM/rings (interconnected) rings
3R O/E/O
Transponders
Components
1998
2000
10000+ km
meshed, flexible
WDM networks
large, full flexible
(integrated) OXC
integrated
optical switches
Opt. 3R
lower cost opt transc.
Optical : 155 Mb
(A|V)DSL, RAN at
2, 10, 50 Mb
Very fast Internet,
Interactive
entertainment
Optical signal
processing
- OTDM
- clock extraction
- short pulse
generation
Optical: 622 Mb
Electrical: up to
100 Mb
Virtual presence for
working, learning and
entertainment
May 1998
Research Work Needed:
• Multiservice access networks (fixed and wireless)
–
to share the cost of fiber plant while the demand of bandwidth increases
– who, what, where, when?
• Network Architectures
– Optimum wavelength routing for the client traffic (ATM. FR, Fast IP,
Gigabit Ethernet)
– Dynamic wavelength assignment and routing, bandwidth on demand
– Network Protection Schemes
– Network control and management, and their compatibility with higher layer
client (SDH, ATM, etc.)
•
– IP & optics mapping
Network Element
– Optical Cross-Connect (OXC) and Optical Add & Drop Multiplexer
(OADM) functionality, capabilities, structures
– Optical Amplifier with wider bandwidth and high gain
– Components are 1/4 or 1/100 cheaper
• Network Control and Management is the key
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DOCUMENTTYPE
Nokia Research Center
TypeYourNameHere
1 (1)
Networking
TypeDateHere
LAYER
FUNCTIONS
TECHNOLOGIES
APPLICATION
Client data
Session control
Data, Voice, Video
TCP …
NETWORK
Addressing
Routing
Switching
IP; ATM, ISDN
MPLS
-routing, O-switching
LINK
Multiplexing
Multiple access
ATM, PDH, SDH, GbE
WDM, OCDMA, OTDM,
O-Burst, O-Tag, O-Packet
PHYSICAL
Coding
Amplification
Supervision
Fiber, lasers, EDFA,
passive optics
S-38.164 Laajakaistainen välitystekniikka - K-2002
Tutorial, optics and networking_JA.PPT / 9.4.2002 / JA page:
Standardization
ANSI
T1X1
ATM
Forum
ITU-T
Optical
Internetworking
Forum
ITU-T
S-38.164 Laajakaistainen välitystekniikka - K-2002
Tutorial, optics and networking_JA.PPT / 9.4.2002 / JA page:
IEEE
IETF
Standardization of optical
networking and internetworking
•Optical Domain Service Interface (ODSI), kick-off meeting, January 18, 2000
•Optical internetworking Forum - OIF
[http://www.oiforum.com]
•Technical Subcommittee - T1A1 Performance and Signal Processing,
[http://www.t1.org/t1a1/t1a1-rms.htm]
•Technical Subcommittee T1E1 - Interfaces, Power & Protection of Networks,
[http://www.t1.org/t1e1/_e1-rms.htm]
•Technical Subcommittee T1M1 - Internetwork Operations, Administration, Maintenance and Provisioning
[http://www.t1.org/t1m1/_m1-rms.htm]
•T1S1 Technical Subcommittee - Services, Architectures and Signaling
[http://www.t1.org/t1s1/t1s1-rms.htm]
•T1X1 Technical Subcommittee - Digital Hierarchy and Synchronization
[http://www.t1.org/t1x1/_x1-rms.htm]
•TIA FO-2 Committee on Optical Communication Systems
[http://www.tiaonline.org/standards/sfg/scope.html#FO-2]
•SONET Interoperability Forum (SIF)
[http://www.atis.org/atis/sif/sifinfo.htm]
•ATM Forum
[http://www.atmforum.com/atmforum/about/intro.html]
•Internet Engineering Task Force (IETF)
[http://www.ietf.org/tao.html]
•ITU-T Study Group 13 – General network aspects
[http://www.itu.ch/itudoc/itu-t/com13/gen_area_35047.html]
•ITU-T Study Group 15 – Transport networks, systems and equipment
[http://www.itu.int/itudoc/itu-t/com15/gen_area_35049.html]
IEEE 802.3 Ethernet in the First Mile Study Group [http://grouper.ieee.org/groups/802/3/efm/public/index.html]
IEEE 802.17 Resilient Packet Ring Working Group [http://www.ieee802.org/rprsg/]
S-38.164 Laajakaistainen välitystekniikka - K-2002
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Provisional conclusions (1/3)
North American Telecom network growth
Relative Load
35
30
25
Voice
Data
35%/Year
20
15
Digital
(data)
10
5
0
1990
10%/Year
1995
2000
2005
Year
Source: Lightwave May-97 (assuming data was 20% of voice 1990)
Factual:
• Explosive bandwidth demand
in fixed transport networks
• circuit switched optical
networking solutions are
penetrating the core and
metropolitan networks with
protocol, bitrate or optical
transparencies
• Strong trend towards packet
orientation (e.g. IP)
Provisional conclusions (2/3)
Issues to be resolved:
• optimization of multiservice access networks to allow convergence to take
place in the physical layer (fiber); simplification of solutions, e.g. QoS?
• Ethernet in the First Mile in 3-5 years very cost effective for residential
access, strong competitor to xDSL and CATV
• Cost effective microwave photonic solutions for radio front-end?
• Evolution of enabling technologies to allow the full functionality of fault
tolerant, flexible optical connection oriented or connectionless networks ?
• Role of higher network layers, e.g. IP, Gigabit Ethernet, 10 Gig-E, ATM,
SDH over WDM/Optical networking ?
• degree of transparency ?
• Effect of fast evolving de-facto standards ?
• Optical signal processing (e.g. OCDMA) in access networks, Lan, MAN
environments ?
• Role of OTDM in transport networks ?
Provisional conclusions (3/3)
Speculative:
• optical burst or label switching?
• optical packet switching?