This document discusses optical spectrum as a service, which allows communication service providers (CSPs) to sell unused optical spectrum. Advances in coherent transport and flexgrid open line systems now enable CSPs to segment spectrum into slices and assign them to different users. This transforms spectrum into a new service that CSPs can offer beyond traditional leased lines. Realizing spectrum as a service requires an open line system with programmable spectrum allocation, flexible grid technology, service demarcation functions, and network slicing through open control and management. Several examples demonstrate how spectrum services are being implemented in multi-domain and multi-operator networks.

1. From leased lines to optical spectrum services
Cornelius Fürst & Henning Hinderthür, ADVA
NGON 2022, Barcelona, June 22, 2022

2. © 2022 ADVA. All rights reserved.
2
AGENDA
What is and what drives “optical spectrum as a service”?
1.
Network elements and functions for spectrum services
2.
Creating spectrum services
3.
Realization examples
4.
From leased lines to optical spectrum services

3. © 2022 ADVA. All rights reserved.
3
Technology progress enables new service definition
Coherent transport interface innovation
• Coherent technology simplifies planning and operation
• Ultra-flexible interfaces and adaptive networking optimize performance
• 400G (Open)ZR+ moves traffic towards customer devices (IPoDWDM)
• New service definitions feasible – wavelength & spectrum
Flexgrid open line system (OLS) technology innovation
• Programmable flexgrid technology with finest grid granularity is
becoming standard
• Flexible use of bandwidth enables new types of optical VPN services
• SDN control automizes path setup
100-800G

4. © 2022 ADVA. All rights reserved.
4
• Optical spectrum is segmented into slices
• Slices can be assigned to different users and applications
• CSPs and carriers can sell unused spectrum
• Bandwidth options beyond leased lines or dark fiber
Monetize unused spectrum and provide differentiated services
Spectrum as a service – What does it mean?

5. © 2022 ADVA. All rights reserved.
5
Market participants of spectrum services
Spectrum
service
Spectrum service
demarcation
Open line system
Users (customers)
• Wholesale users
• Carrier to carrier spectrum handoff
• Datacenter operators
• Large enterprises
• R&E
Providers
• Bandwidth wholesaler carriers
• R&E Operators
• Co-op / shared infrastructure providers
NMS/Controller

6. © 2022 ADVA. All rights reserved.
6
A truly open line system with open control and management is key
Spectrum as a service – the OLS building blocks
Programmable flexgrid technology
Gridless spectrum allocation
Support for any coherent format and baud rate
Service demarcation and monitoring
Optical spectrum policing
Strict user separation
Open optical line system
Truly open and disaggregated OLS design
Full OLS characterization (GOSNR)
Open control and management
Programmability with open APIs
Network slicing with client control

7. © 2022 ADVA. All rights reserved.
7
Practical requirements for successful realization
Support on multiple layers:
• Spectrum (Media channel)
• Wavelength (OTSi/OTSiA)
• Mapped channel (ODU)
• Multiplexed (ODUk)
Open spectrum service
gateway between domains
and participating organi-
zations, with policing.
Well defined procedures for:
• Planning
• Installation
• Reliable service
commissioning
Service support Open gateway Procedures
Collaboration between
operators while keeping
privacy on network domains
(detailed parameters and
network control)
Collaboration
Analog services have higher operational complexity than digital leased lines

8. © 2022 ADVA. All rights reserved.
8
Spectrum service support
ITU G.807, G.709, G.798
OTSi : Optical Tributary Signal
OTSiA : OTSi Assembly with non-associated overhead
Spectrum modelling in software
Spectrum services based on standards:
• Built on Flexgrid OLS layer
• Bandwidth management software creating Network Media Channel
(NMC) and Network Media Channel Groups (NMCG)
Spectrum services require individual channel (OTSi)
provisioning:
• OTSi based equalization of spectrum services in the OLS
• Definition of interdomain interface
• Wavelength and spectrum services only differ in number of channels
Spectrum reservation for scalable spectrum service
Spectrum service
reservation
NMCG
OTSiA
Multiple OTSi
OTSiA
Single OTSi
NMC
Transmit spectrum

9. © 2022 ADVA. All rights reserved.
9
Wavelength selective device required
Spectrum demarcation functions:
• Spectrum monitoring
• Passband configuration
• Ingress power level control – based on PSD*
• Spectrum policing and enforcement
• Multiplex to network ports
Demarcation: open spectrum gateway
Spectrum
Services
OLS / ROADM
degree
Spectrum service
demarcation
Service 1
Service 2
Service N
*power spectral density

10. © 2022 ADVA. All rights reserved.
10
• Setup of the individual interfaces (OTSi)
• End-to-end performance characterization
Path planning
Performance estimation
• Routing and selection of candidate paths
• Calculating constraints for services
Dedicated OLS planning tool provides GOSNR limits (anonymous parameter)
Channel (OTSi) setup with performance verification
Non-digital services require reliable commissioning procedures

11. © 2022 ADVA. All rights reserved.
11
Two-step approach: Performance estimation followed by verification
• Installation and provisioning of a service without complete network knowledge
• Characterization of the planned and implemented path (NMC)
• GOSNR / GSNR based probing methods
Path verification
Service setup with path characterization
Q
2
(dB)
Measured OSNR/Estimated GOSNR (dB)
100G QPSK
200G QPSK
300G 8QAM
400G 16QAM
Characterized probing units
Kaeval, K., Myyry, J., K., Grobe, K., Grießer, H. and Jervan, G.,
2021, October. “Concatenated GSNR Profiles for End-to-End
Performance Estimations in Disaggregated Networks”. In
2022 Optical Fiber Communications Conference and
Exhibition (OFC) (pp. 1-3).IEEE.

12. © 2022 ADVA. All rights reserved.
12
Single-domain Network Media Channel (NMC)
• Customer and network operator negotiate characteristics of spectrum service
• Network operator provides path (via domain controller) and performance estimate (GOSNR)
• Demarcation device provides signal control and policing
Single domain
Control: Using APIs & SDN for automation
Domain controller A
Network A
NBI
Spectrum service
customer
Gateway device

13. © 2022 ADVA. All rights reserved.
13
Multi-domain NMC
• Operators and customer negotiate characteristics of spectrum service
• Same profile on all demarcation devices: OTSiA, individual OTSi’s, power levels
• Requires collaboration of domain operators
• Routing is domain internal
Multiple domains
Control: Using APIs & SDN for automation
Domain controller B
Domain controller A
NBI
NBI
Spectrum service
customer
Network B
Separate domains
Network A

14. © 2022 ADVA. All rights reserved.
14
Spectrum services in a multi-operator network
Example 1 – Baltic Optical Network
• Different vendors and network technologies
• Unified spectrum allocation
• Transparent ROADM-based interconnects at border crossings
• Automated domain-based service creation
• Unregenerated, protected end-to-end services
• >8800 km European network
• Connecting Estonia, Latvia & Lithuania
• 3 national and 1 ultra long-haul domain
Multi-operator network
Network concept

15. © 2022 ADVA. All rights reserved.
15
Ultra long-haul transmission with interdomain traffic
• Interdomain express links using ROADM client
connections
• >2.000km / 10.000km with 800/400G coherent
interfaces
Example 2: Spectrum gateway and reach
800G over 2.266km
4.14bits/sym
28 WSS modules
44 EDFA, 16 Raman
Long term error free
400G over 10.000km
2bits/sym
>100 WSS modules
>150 EDFA, >60 Raman
Error free testing
Source: CSC - IT Center for Science Ltd

16. © 2022 ADVA. All rights reserved.
16
Coherent pluggable based services over open OLS
• Customer lab test configuration >1.000km, 75GHz channel spacing
• Error free performance using off-the-shelf 400G OpenZR+ optics, 26 Tb/s fiber capacity
Example 3: 400G OpenZR+ with open OLS
EDFA/Raman
32-degree
ROADM
75GHz Add-drop
ADVA FSP 3000 OLS
400G
OpenZR+
400G
OpenZR+

17. © 2022 ADVA. All rights reserved.
17
OOPT-CANDI proof of concept (PoC) 2021
Example 4: SDN automation
Integration validation across several
functionalities:
• Network topology discovery of the open
OLS and OTs into the optical SDN controller
• On-line provisioning of optical circuits using
an external vendor-neutral planning tool
• Establishment of optical circuits over partially
disaggregated OLS
Source: Telecom Infra project
Service planning and creation in multivendor optical networks
Multi-vendor implementation

18. © 2022 ADVA. All rights reserved.
18
Extending service offering from leased lines to spectrum
Spectrum as a service – your benefits
New service types for emerging end user
demands
• Enables CSPs to offer differentiated services and
enables new forms of revenue generation
• More customers options for bandwidth addition
• Requires an open system - better with
demarcation, control/automation and (some)
standardization
• Similar service attributes as leased lines, e.g.,
resiliency (restoration)

19. Thank you
IMPORTANT NOTICE
ADVA is the exclusive owner or licensee of the content, material, and information in this presentation. Any reproduction, publication or reprint, in whole or in part, is strictly prohibited.
The information in this presentation may not be accurate, complete or up to date, and is provided without warranties or representations of any kind, either express or implied. ADVA shall not be responsible for and disclaims any liability for any loss or damages, including without limitation,
direct, indirect, incidental, consequential and special damages, alleged to have been caused by or in connection with using and/or relying on the information contained in this presentation.
Copyright © for the entire content of this presentation: ADVA.
info@adva.com