Transcript THE BIG PICTURE - University of California, Berkeley

Optical Networking
CS 294-3
2/5/2002
John Strand
AT&T Optical Networks Research Dept.
[email protected]
U. of California - Berkeley - EECS Dept.
[email protected]
The Views Expressed In This Talk Are The Author’s. They Do Not Necessarily Represent
The Views Of AT&T Or Any Other Corporation Or Individual.
John Strand
1/18/2002
1
SONET Rates
Level
Optical
Designation
Bit Rate
(Mb/s)
STS-1
OC-1
51.840
STS-3
OC-3
155.520
STS-12
OC-12
622.080
STS-48
OC-48
2,488.320
STS-192
OC-192
9,953.280
STS-768
OC-768
39,813.120
STS
OC
= SYNCHRONOUS TRANSPORT SIGNAL
= OPTICAL CARRIER
(“..result of a direct optical converions of the STS after
synchronous scrambling” - ANSI)
EC (Not Shown) = ELECTRICAL CARRIER
John Strand
1/18/2002
2
Basic Service Types
Central
Office
CPE
PSTN
"POTS"
PBX
Switch
• ~ 100 Intercity
Switches*
Transport Network
Private Line (PL)
• Shared By Many
Services
• ~10x As Many Offices*
POTS: Plain Old Telephone Service
* ATT Network
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Entering The Transport Network
64 kb/s
POTS
&
VG PL
1
O
O
O
O
24
O
O
1.5 Mb/s
M
U
X
1.5 Mb/s PL
45 - 2500 Mb/s PL
[1Gb Ethernet]
45 - 622
Mb/s
M
U
X
2.5 - 10
Gb/s
M
U
X
W
D
M
Backbone
Fiber
Network
2500 - 10,000 Mb/s PL,
10 Gb WAN Ethernet *
10 Gb WAN Ethernet
• SONET Framed - 9.953 Gb/s
• Asynchronous
POTS: "Plain Old Telephone Service"
VG:
Voice Grade
PL:
Private Line
John Strand
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4
Fiber Structure
Pure Glass Core
Lightpack Cable Design
8.3 micron*
Glass Cladding
Protects “core”
Serves as a “Light guide”
125 micron
Inner Polymer Coating
Outer Polymer Coating
Protection Layers
250 micron
Single Fiber
Typical Loss: 0.2 – 0.25 dB/km
Plus Connector Loss
* Single Mode Fiber; Multi-Mode Has A 50 Micron Core
John Strand
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Service Routing
Service Layer
(e.g., POTS or PL)
Transport Layer
John Strand
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Optical Amplifier/WDM Revolution
Frequency-registered
transmitters
Receivers
l1
R
All-Optical Amplification
Of Multi-Wavelength Signal!!!
l2
l3
R
WDM
Mux
OA
OA
WDM
DeMux
R
40 - 120 km
(80 km typically)
lN
Up to 10,000 km
(600 km in 2001 basic commercial products)
WDM: Wavelength Division Multiplex
OA: Optical Amplifier
R
John Strand
1/18/2002
7
Single Fiber Capacity
Gb/s
5120
1280
Moore's
Law
320
80
20
1996
1998
2000
2002
2004
Bandwidth
Capacity = (Bandwidth/ l) * (Bits / l)
Source: K. Coffman & A. Odlyzko, “Internet Growth: Is There A Moore’s Law For Data Traffic?” (research.att.com/~amo)
John Strand
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Transport Layer Model
Characteristic Technologies
PL
Circuit/Packet Switching
Router
Voice Switch
DS3 or STS-N
(<= 622 Mb/S)
PL
Digital Transmission
(SONET)
STS-48 or 192
(2.5 - 10 Gb/Sec)
PL
Digital Cross-Connect (DCS)
Add-Drop Multiplexer (ADM)
Single "wavelengths"
Optical Layer
Multi-Wavelength
Wavelength Division Multiplexer (WDM)
Optical Cross-Connect (OXC)
Multi-wavelength bundles
(<= 400 Gb/s)
Media Layer
Fiber
John Strand
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Opaque Wavelength Path Crossconnect
Optical transport system
(1.55 mm)
Standard
cross-office optics
(1.3 mm)
Optical transport system
(1.55 mm)
Add ports
...
= node-bypass
...
...
(Optical or
Electronic
Transparency
Interior)
Fibers
Out
...
...
...
Fibers
In
Wavelength Path
Crossconnect
...
...
...
...
l-Mux
Drop ports
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Opaque Wavelength Path Crossconnect
(Electrical Fabric)
1-Bay Capacity:
640 Gb/s
®
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11
An 8 x 8 Switch
Chip size: 1 cm x 1 cm
Source: L-Y. Lin
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Outline
• Transport - Traditional TDM Networks
• Optical Networking
• Optical Networking & IP
Concentrate On Intercity Networks
• Time Constraint
• Metro, Access Optical Networks More Complex, Less Mature
John Strand
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IP Transport
Data Services
(Mostly IP-Based)
Voice & Other
TDM-Based Services
DS1 (1.5 Mb/Sec)
Wideband & Broadband
DCS Layers
Transport For IP Defining Functionality
Of These Interfaces
DS3 (45 Mb/Sec) STM-4 (622 Mb/Sec)
Digital Transmission
Layer
IP For Transport Introducing IP Functionality
Into The Optical Layer
STM-16c (2.5 Gb/Sec) STM-64c (10 Gb/Sec)
Optical Layer
Proprietary
(20 Gb/Sec - 400+ Gb/Sec)
Media Layer
John Strand
1/18/2002
14
IP For Transport
Replacing The OLXC With A Router
IP
Services
Non-IP
Services
OXC
OLXC
Office Architecture
Non-IP
Services
IP Router
“Big Fat Router”
Office Architecture
John Strand
1/18/2002
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IP For Transport
Comparing The Architectures
IP Router
Terminating (1 – a)
Ports & Assumed Costs
OLXC
$x Per OC48
IP Router $y Per OC48
OLXC
IP Router
Through (a)
OLXC
Office Architecture
•
•
“Big Fat Router”
Office Architecture
OLXC Architecture Less Expensive If:
OLXC Cost x
<a
Router Cost y
Typical Values:
•
a = 0.8
•
x/y << 0.2
John Strand
1/18/2002
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MPLS Transport Hierarchy
MPLS
IP
X s
Physical Transmission System
• SONET (STS-N)
• OCh
• Etc.
LSP
X
LSP s
LSP t
LSP u
LSP
Y
LSP a
LSP s
LSP t
• Label Switched Path's (LSP's) Are LOGICAL, NOT PHYSICAL
• Need Not Occupy Bandwidth
•Specific LSP’s Change At Each MPLS Node:
z End-to-end connection defined at set-up
John Strand
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MPLS Tunneling
POP 3
PUSH
7
42 11
7
LSP 7
88 11
SWAP 7=>11
PUSH 42
3
POP 88
SWAP 11=>3
SWAP 42 => 88
LSP 3
LSP 11
LSP 42
LSP 88
• "Virtual" Muxing - No Utilization Penalty
• This Is A Key Driver For Replacing TDM
John Strand
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TDM Multiplexing
Tunneling Using MPLS LSP's Is Analogous To TDM Multiplexing
DS1
DS3
STS-48
STS-48
DS3
DS3
John Strand
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From MPLS To GMPLS
Implicit Label
(1)
PUSH
7
42 11
7
LSP 7
Implicit Label
(2)
SWAP 7=>11
PUSH 42
POP 3
88 11
3
POP 88
SWAP 11=>3
SWAP 42 => 88
LSP 3
LSP 11
LSP 42(1)
STS-192
LSP 88(2)
STS-192
GMPLS: Generalized MPLS
John Strand
1/18/2002
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GMPLS In An OXC Network
1. Select source, destination, and service
2. OSPF determines optimal route
3. RSVP-TE/CR-LDP establishes circuit
Label Request Message
Label Mapping Message
Vision:
• Provisioning Time: Weeks To Milliseconds
• Greatly Simplify Process
ISSUE: Standards Lagging Need - Proprietary Control Planes
Source: Sycamore OFC2000
Are Being Deployed Rapidly
John Strand
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GMPLS Vision
Many Technologies - One Network
LS: Lambda Switched
FS: Fiber Switched
PS: Packet Switched
FA: Forwarding Adjacency
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GMPLS Overlay Network Model
~
~
~
~
Connection
Requests, etc.
~
~
Router
Optical
Network
~
~
Router
UNI
~
~
• Overlay Network
– Optical Network (OXC) computes the path
– Network Level Abstraction For IP Control Plane
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GMPLS Peer Network Model
~
~
~
~
Topology &
Capacity Information
Router
~
~
Network
Signalling
Optical
Network
~
~
Router
~
~
• Peer Network
– Router computes the path
(Routers have enough information about the characteristics of the optical
devices/network)
– Link-level abstraction For IP Layer Control Plane
John Strand
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Canarie OBGP Vision
School
Aggregating Router
ISP Controlled
Optical Switch
ISP A
Dark Fiber
IGP
OiBGP
BGP
Multi Home Router
IGP
University
X
Dark Fiber
Mapped to
Dim
Wavelength
IGP
Customer Owned
Dark Fiber
B. St. Arnaud
Customer Controlled BGP neighbors
Optical Switch
ISP Controlled
Optical Switch
IGP
OBGP
OBGP
OBGP
University
Y
ISP B
John Strand
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Optical Interworking Forum
Services Concept
Customers buy managed
service at the edge
ISP
AS 4
AS 1
Optical VLAN
AS 1
Customer
AS 3
BGP Peering is
done at the
edge
• Bandwidth On Demand - Connection Request
Over UNI Specifying QoS Desired - Overlay Model
• OVPN - Dedicated Subnet Configured By
John Strand
AS 2 Customer - Peer Model
1/18/2002
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Examples of network views
• View from domain A via a distance-vector or pathvector protocol
Domain 2
Reachable
Address list
Domain 1
Reachable
Address list
Domain 4
Reachable
Address list
Domain 3
Reachable
Address list
Domain 5
Reachable
Address list
John Strand
1/18/2002
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Examples of Network views
• View from any domain of the rest of the network via a link state
protocol
Protection 1:N, N=3
Available BW = …
SRLG = …
Domain 1
Reachable
Address list
Protection 1+1
Available BW = …
SRLG = …
Protection 1+1
Available BW = …
SRLG = …
Protection 1+1
Available BW = …
SRLG = …
Domain 4
Reachable
Address list
Domain 3
Reachable
Address list
Protection 1:N, N=10
Available BW = …
SRLG = …
Domain 2
Reachable
Address list
Protection 1+1
Available BW = …
SRLG = …
Protection 1:N, N=7
Available BW = …
SRLG = …
Domain 5
Reachable
Address list
John Strand
1/18/2002
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Initial OIF NNI Target
User control
Domain
User control
Domain
Load
Balancer
L2/L3
Load
Balancer
firewall
L2/L3
firewall
L2/L3
Load
L2/L3
firewall
Balancer
Load
Balancer
NNI
UNI
Control Domain
C
firewall
UNI
Control Domain
A
NNI
NNI
Control Domain
B
Single carrier’s network
User control
Domain
Load
Balancer
L2/L3
firewall
L2/L3
Load
Balancer
firewall
Why Single Carrier Multi-Domain First?
• Standards Lag Deployment - Vendor Proprietary Control Planes
• Rapid & Unpredictable Technological Change Makes It Unlikely
That Standards Will Keep Up
• Uncertain Business Model
Initial Multi-Carrier NNI Likely To Be LEC/IXC (JLS Opinion)
29
John Strand
1/18/2002
oif2001.639 - Application-Driven Assumptions And Requirements
Metro/Core Characteristics
1. Significant Differences In Technology, Economic Trade-Offs, & Services Supported
2. Likely To Be Multi-Vendor
3. Proprietary Or Customized IGP's Are Likely
4. Significant Operational Autonomy
• Information Trust, Not Always Policy Trust
• Domains Likely To Require Control Of The Use Of Their Resources
5. Routing
• Carrier-Specific
• NMS May Be Involved
• High Unit Costs, Long Connection Times Make Economics An Important Consideration
Metro
Metro
Y
Metro
X
J
K
A
6. Conduit & Fiber Cable Sharing Make SRG Information Across
Domains Complex - Will Frequently Not Be Available
John Strand
1/18/2002
30
oif2001.639 - Application-Driven Assumptions And Requirements
Metro/Core Characteristics
1. Significant Differences In Technology, Economic Trade-Offs, & Services Supported
2. Likely To Be Multi-Vendor
3. Proprietary Or Customized IGP's Are Likely
4. Significant Operational Autonomy
• Information Trust, Not Always Policy Trust
• Domains Likely To Require Control Of The Use Of Their Resources
5. Routing
• Carrier-Specific
• NMS May Be Involved
• High Unit Costs, Long Connection Times Make Economics An Important Consideration
Y
Metro
Metro
Metro
Y
J
K
A
6. Conduit & Fiber Cable Sharing Make SRG Information Across
Domains Complex - Will Frequently Not Be Available
John Strand
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oif2001.639 - Application-Driven Assumptions And Requirements
Multi-Vendors In Backbone - Characteristics
1. Proprietary Or Customized IGP's Are Likely
2. Information & Policy Trust Not Likely To Be An Issue
3. Vendor-Specific Technologies & Constraints Not Captured In Standards Are Likely
(E.g., All-Optical, Tunable Lasers, Adaptive Wavebands)
B
M
S
T
K
S
T
B
M
N
S
Q
P
T
Large A Small B
R
Express
Domain of
Transparency
(Vendor B)
Small A
Large B
U
K
J
Routing Costs: A(nodes) + B(distance)
(Vendor A)
L
P
N
Z
Y Opaque
Network
R
U
J
A
Q
P
N
M
L
K
J
A
L
Q
U
Z
Y
R
John Strand
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IP Transport
Data Services
(Mostly IP-Based)
Voice & Other
TDM-Based Services
DS1 (1.5 Mb/Sec)
Wideband & Broadband
DCS Layers
Transport For IP Defining Functionality
Of These Interfaces
DS3 (45 Mb/Sec) STM-4 (622 Mb/Sec)
Digital Transmission
Layer
IP For Transport Introducing IP Functionality
Into The Optical Layer
STM-16c (2.5 Gb/Sec) STM-64c (10 Gb/Sec)
Optical Layer
Proprietary
(20 Gb/Sec - 400+ Gb/Sec)
Media Layer
John Strand
1/18/2002
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Entering The Transport Network
64 kb/s
POTS
&
VG PL
1.5 Mb/s
1
O
O
O
O
45 - 622
Mb/s
2.5 - 10
Gb/s
1
O
O
o
24
o
o
o
1.5 Mb/s PL
45 - 622 Mb/s PL
1 - 10 Gb/s PL
28
BW
Growth
Rates
Backbone
Fiber
Network
POTS: "Plain Old Telephone Service"
VG:
Voice Grade
PL:
Private Line
John Strand
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US Domestic Backbone (Mid-’99)
268,794 OC-12 Miles
John Strand
1/18/2002
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Transport Layering
Data Services
(Mostly IP-Based)
Voice & Other
TDM-Based Services
DS1 (1.5 Mb/Sec)
XX
X
X
Wideband & Broadband
DCS Layers
DS3 (45 Mb/Sec) OC-12 (622 Mb/Sec)
OC-48c (2.5 Gb/Sec) OC-192c (10 Gb/Sec)
Digital Transmission Layer
• ADM's
•Rings
Functionality
& Value Added
Optical Layer
• Optical Transport Systems (DWDM, OA,OADM)
•"Optical Cross-Connects"
Proprietary
(20 Gb/Sec - 400+ Gb/Sec)
Media Layer
•Fiber
•Conduit
John Strand
1/18/2002
36
Transport For IP
Customer Drivers
Possible Solution Elements
• Price - $/OC48/month
•Rapid Provisioning
• Availability
• How Quickly
• Where
• Optical Network Interworking
•Heterogeneous Technologies
• Metro/Core
• Other Backbone Providers
• Displacement Of Internal ISP Costs
• Interfaces
• Cost Of Reliability
• Buffer Capacity
• Peak Loads
• Traffic Shifts
• Traffic Growth
• Network Management
• Differentiators
• Availability
• QoS
•Flexible Bandwidth
• Asymmetric Circuits
• Concatenated Links
• Virtual Concatenation
• Inverse Multiplexing
•Additional Customer Restoration Options
• Re-Provisioning
• Customer Control
• Speed Options
• Sub-OC48 Functionality
• Layer 1 Interface Enhancements
John Strand
1/18/2002
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Restoration Refresher
Key Trade-Off
Restoration Granularity
Services
Layers
DCS
Layers
Unit Capacity Cost
Connection
STS-1 => STS-12
Digital
Transmission
Layer
STS-48+
Optical
Layer
l or Fiber
• Services Layer (IP) Can Restore Exactly The Right Connections
• Optical Layer More Economical If Large Bundles Of Connections Need
To Be Restored
John Strand
1/18/2002
38
ISP Peering Relationships
Peer
Provider
Peer
(Frequently) No $$
Customer EXPENSIVE
John Strand
1/18/2002
39
Transport For IP
Reducing The BGP Hop Count
R
C
B
A
X
Hi-Usage
Trunks
Tier 1 ISP
Optical
Direct Connects
Y
Z
Toll Switching Hierarchy
Regional ISP
Local ISP
Internet ISP Hierarchy
Typical Transit Cost (Telia): $1K - 10K / Mbps /Year
John Strand
1/18/2002
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References
• T. E. Stern & K. Bala, Multiwavelength Optical Networks, Addison-Wesley, 1999
• J. L. Strand, “Optical Network Architecture Evolution”, chapter in I. Kaminow and T. Li (eds.),
Optical Fiber Telecommunications IV, Academic Press, to appear March 2002
• R. Ramaswami and K. N. Sivarajan, Optical Networks: A Practical Perspective,
San Francisco: Morgan Kaufmann, 1998.
• R. H. Cardwell, O. J. Wasem, H. Kobrinski, “WDM Architectures and Economics in Metropolitan Areas",
Optical Networks, vol. 1 no.3, pp. 41-50
• O. Gerstel and R. Ramaswami, "Optical Layer Survivability: A Services Perspective",
IEEE Communications Magazine, vol. 38 no. 3, March 2000, pp. 104-113.
• R. D. Doverspike, S. Phillips, and Jeffery R. Westbrook, "Future Transport Network Architectures",
IEEE Communications Magazine, vol. 37 no. 8, August 1999, pp. 96-101.
• R. Doverspike and J. Yates, "Challenges for MPLS in Optical Network Restoration", IEEE Communications
Magazine, vol. 39 no. 2, Feb. 2001, pp. 89-96.
• M. W. Maeda, "Management and Control of Transparent Optical Networks", IEEE J. on Selected Areas In
Communications, vol. 16, no. 7, Sept. 1998, pp. 1008-1023.
• J. L. Strand, J.; A. L. Chiu, , R. Tkach,. “Issues For Routing In The Optical Layer”, IEEE Communications Magazine,
2/2001, vol. 39, no. 2, pp. 81 –87
• John Strand, Robert Doverspike, Guangzhi Li, “Importance of Wavelength Conversion In An Optical Network”,
Optical Networks Magazine, vol. 2 No. 3 (May/June 2001), pp. 33-44
•R. W. Tkach, E. L. Goldstein, J. A. Nagel, J. L. Strand, “Fundamental limits of optical transparency”,
OFC '98, pp. 161 -162
•A. L. Chiu, J. L. St,rand, “Joint IP/Optical Layer Restoration After A Router Failure”, OFC 2001, vol. 1, pp. MN5_1 -MN5_2.
John Strand
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Some Relevant U.S. Web Sites
“Tier 1” Inter City Service Providers
• AT&T
• MCI Worldcom
• Sprint
http://www.att.com
http://www.wcom.com
http://www.sprint.com
New Entrants
• Qwest
• Level3
• Frontier
• Williams
http://www.qwest.com
http://www.Level3.com
http://www.frontiercorp.com
http://www.williams.com
Major Equipment Providers
• Lucent
• Alcatel
• Nortel
• Cisco
• NEC
http://www.lucent.com
http://www.alcatel.com
http://www.nortel.com
http://www.cisco.com
http://www.nec.com
Standards Organizations
• ITU
• T1
• OIF
• IETF
• ATM Forum
http://www.itu.int
http://www.t1.org
http://www.oiforum.com
http://www.ietf.org
http://www.atmforum.com
New Business Models
• Band-X
•Arbinet
http://www.band-x.com
http://www.arbinet.com
Government Sites:
• FCC
• NTIA
http://www.fcc.gov
http://www.ntia.doc.gov
New Equipment Vendors
• Ciena & Lightera
• Cisco & Monterey
• Avici
• Juniper
• Sycamore
http://www.ciena.com
http://www.montereynets.com
http://www.avici.com
http://www.juniper.net
http://www.sycamore.com
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1/18/2002
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