1. Bjarke Skjoldstrup Project Manager, TDC A/S, Denmark
Business Potentials and Practical Operational Aspects of Alien Wavelength Services
TNC16, June 2016, Prague, Czech Republic
Bjarke Skjoldstrup
Project Manager, TDC A/S, Denmark
Calibration of the size of the window for the presentation notes --

2. Concept behind use of Alien Wavelengths in the TDC network
Router-to-router transmission
Relevant scenario: Capacity and reach demands equal the maximum achievable per wavelength in the optical network
Transport Network
Router A
Router B
100G grey interface
Optical Network
100G coherent interface
Traditional POP solution:
Engine
Interface
Transponder
Multiplexer
Router A
OTN node
100G coherent interface
Optical Network
POP solution using Alien Wavelength:
Engine
Interface
Besides bringing the cost down AW simplifies the network
AW is the preferred method used for transport in the IP/MPLS core network of TDC
Multiplexer
Router A
OTN node

3. Current use of Alien Wavelengths in TDCs network
TDCs IP/MPLS core network
100 Gbit/s Alien Wavelengths
21 Alien Wavelength trails
OTN managed OCh trails
OCh termination divided between two vendors
Physical path: km
100G links with AW using PM QPSK modulation and SD FEC.
Our experience in TDC is that the AWs are easy to operate within the company.
We have found that the organisational structure is important for facilitating the use of AWs.
Based on “TDCs new IP Core, 2015: Introducing 100G interfaces and Alien Wavelengths”
Martin Skafte, TDC A/S
From TDC meeting 12th of June, 2015

4. Interworking in the organizational structure (traditional workflow)
Routing
Transport
Operation
ODNB
ODND
Capacity Planning
OTKI
OTKI
System Planning
OTVB
OTVB
Optical Network
Engine
Interface
Transponder
Multiplexer
Router A
OTN node
Workflow is traditionally organized by using a line structure with boundaries defined by the interfaces of the technological platforms.
Great structure if the network functionallity to be managed is clearly confined within the platforms.
Well-defined demarcation between departments responsibilities (defined by the physical network)
Clear processes for how things are done
Flexibility is a soft spot in this structure

5. Cross-functional teamwork (Alien Wavelengths)
Routing
Transport
Optical power level alarms
Re-tuning of VOAs
Operation
ODNB
ODND
Capacity Planning
OTKI
WSS pixel adjustments
OA gain tilt adjustments
System Planning
OTVB
Change of optical TX power
Optical Network
Optical Network
Engine
Interface
Multiplexer
Router A
OTN node
When AW are provided from outside the Transport platform the line organisation is challenged.
The actions on the Routing or the Transport side can have crucial implication on the performance of the other.
Each individual staff member need to have a more detailed knowledge of the other platform when using AW.
As an example: the maintenance procedure for the optical interface …
In general an excellent team work is required between the responsible for the AW source and the responsible for the host Transport network.
Excellent teamwork experience – but no clear demarcation point for responsibilities
Assistance across the organizational borders is required
Very few TelCos have successfully done this

6. Work flow comparison example
IP/MPLS link capacity expansion or new deployment
Allocation of the responsibility of specific process steps
Task\Organisation
Traditional
Alien Wavelength
Routing
Transport
Identification of demand
Link interface
Transport path ●
(trigger)
(resources)
Analysis & design of transport path
Upgrade and configuration of
AW has an impact on many parts of the organisation. …
In the Traditional configuration the Routing department focus on upgrading the grey interface in the routers, and the Transport department focus on providing the required capacity for the transport path.
The AW configuration offloads the Transport department by moving the responsibility for the end-to-end design and implementation of the path to the Routing department.
In general the main work flow change by introducing the AW is a move of the responsibility from the Transport organisation to the owner of the Alien wavelength in the Routing organisation.

7. Monitoring of Alien Wavelength trail performance
For each ROADM along the OCh trail:
Optical line receive power
Optical line transmit power
Optical signal-to-noise ratio on line receive port
Optical signal-to-noise ratio on line transmit port
For each termination point of the OCh trail:
Router interface up/down
Traffic load in/out via the interface
BER before and after FEC
Optical input and output power
Estimated cromatic dispersion
Q-value and Electrical Signal-to-Noise Ratio
A major issue for the operation of the AW in the Transport department is the reduction in the service and network performance management of the full trail.
The full trail information is made available for the Transport department in TDC, by extracting the relevant data from the Routing management system and presenting it on a web interface to the operator of the Transport network.
Brings the operation of the AW in TDC on par with the native wavelengths of the host network in the Transport department.
Sufficient solution for supporting the fault and maintenance procedures … the basic operational foundation for creating a managed AW service is not complicated.

8. Alien Wavelength as a commercial service offer from TDC
100G coherent Alien Wavelength service evolution time line
Introduction of
OTN network
Host network
support
Technical
Launch
 2006
Early 2015
2015
Commercial ?
From a technological and operational point of view 100G AWs based on coherent technology can without any major efforts be offered to end customers as a new low cost type of transparent transport service.
The time line …
We are currently collecting experience from the operation in order to develop the technology to become a commercial product.
Lack of a common reference for how to specify an AW service – and also the lack of interest from the market currently.
But for now we can list a number of factors which influence the business potential.

9. Alien Wavelengths – pros and cons for commercial use
Significant cost reduction for the operator
Fewer components
Less complicated upgrade procedures for the equipment
Improved data transmission integrity for the customer
New type of service offering in the Whole Sale market
Cons
Significant cost increase of customers interface
Co-location required
Customer/Operator Trail management split
Cannibalization of current service offerings
AW agreement impact the physical network planning
Customer responsible for data performance
Customer behavior may impact other services
Cost and the simplicity.
Improvement of the integrity between the end terminals.
Facilitates proactive fault management by the customer.
The customer need to invest in a more advanced optical line interface.
Optical power requirement between the host and the AW equipment dictates that the equipment must be co-located.
AW service is moving requests from the existing broadband services rather than creating new demands.
Agreement on how to handle the shared customer-operator responsibility for ensuring the performance of the customers service as well as the performance of the operators network.
AW service is strongly dependend on the specific physical parameters for the particular demand and therefore it is not straight forward to introduce an AW service and to sell it off the shelf …

10. PM BPSK, PM QPSK and PM DQPSK
It is not straight forward for the operator: Key parameters for an Alien Wavelength Service Agreement
The host network operator should as minimum disclose data like these
Parameter
Unit
Value
Wavelength range accepted (50 GHz ITU-T grid)
THz
192.1 – 196.1
Modulation format accepted -
PM BPSK, PM QPSK and PM DQPSK
Input Power range accepted
dBm
-5.0 – 0.0
Output Power range delivered
-16.0 – 0.0
Site A
Stockholm
Site B
Malmö
Length of the wavelength path km
812.6
Transmission fiber type
ITU-T G 652
Launch power per wavelength
+1.0
Number of ROADM sites in the wavelength path 6
Optical Bandwidth of each ROADM (Gaussian, -1 dB) nm
0.2
Chromatic Dispersion of the wavelength path
ps/nm
12,654 – 15,288
Mean Differential Group Delay of wavelength path ps
3.6
Optical Signal to Noise Ratio of received signal dB
>21.8
The technical challenge can be illustrated by the set of key parameters which should be part of a Service Specification and a Service Level Agreement for an AW service type.
The operator must disclose data for the optical network segment in question to make it possible for the customer to evaluate the transparancy and performance of the AW transport.
Some of these parameters are usually considered business sensitive and many operators may find it difficult to disclose these network details to the customer, which may be a competing operator in the Whole Sale marked.

11. It is not straight forward for the customer: Key parameters for an Alien Wavelength Service Agreement
The Alien Wavelength customer should as a minimum specify data like these:
Parameter
Class
Unit
Value
Transmitter launch power range
Mandatory
dBm
Receiver input power range
Minimum (at given dispersion and OSNR tolerance values)
Maximum allowable
Line Rate
 Gbit/s
Modulation format  -
Transmitter Side-Mode Suppression Ratio ( GHz from carrier) dB
Differential Group Delay tolerance, maximum
Optional ps
Polarisation Dependent Loss tolerance, maximum
Bandwidth of Optical Passband centered on ITU grid
Minimum and maximum tolerable
GHz
Wavelength Excursion off ITU grid, maximum tolerable pm
Manufacturer and the model/type of the Wavelength source/sink
The customer should disclose data for the parameters which characterize the AW in the optical network.
The AW service requires an openness between the operator and the customer which for many reasons is uncommon in the existing Whole Sale marked. It also requires unusual commitments from both parties with respect to maintenance and fault management.

12. Current status is …
100G coherent AW are easy to operate inside the company
A flexible organisation is required
The technological foundation for operating an Alien Wavelength service is simple to establish
Converting the Alien Wavelength technology to a service offered to external customers is a serious challenge
The main issues are non-technical
Involves unusual commitments from the customer and the operator regarding maintenance and fault management
Lack of standardization and support from a number of transport system vendors has hindered a technology push
Alien Wavelengths offered as a commerciel service will need a market pull to become a reality for an operator as TDC