In this page are presented a set of real-world optical transport network topologies.

The parameters for some of the networks were obtained with the dimensioning commercial software OPNET SP Tranport Planner 15 (www.opnet.com ).



South African National Research Network (SANReN)

Topology 
SANREN Topology
Reference - http://www.sanren.ac.za/design/backbone/ (Accessed: Jun. 02/2014)

Parameters

Variable Description Value
N Number of  Nodes  7
L Number of Links  7
<δ> Mean Nodal Degree  2.00
<h> Mean Number of Hops  for Working Paths  2.00
<h'> Mean Number of Hops  for Backup Paths  5.00
<s> Mean Link Length (km) 462 


Via Network

Topology 
ViaNet Topology
Reference - http://www.vianetworks.net/datacenter-globalnetwork.php (Accessed: Jun. 18/2009)

Parameters

Variable Description Value
N Number of  Nodes  9
L Number of Links  12
<δ> Mean Nodal Degree  2.67
<h> Mean Number of Hops  for Working Paths  1.97
<h'> Mean Number of Hops  for Backup Paths  3.60
<s> Mean Link Length (km) 571 


Bulgarian Research and Education Network (BREN)

Topology 
BREN Topology
Reference - http://www.bren.acad.bg/images (Accessed: Nov. 05/2009)

Parameters

Variable Description Value
N Number of  Nodes  10
L Number of Links  11
<δ> Mean Nodal Degree  2.20
<h> Mean Number of Hops  for Working Paths  2.97
<h'> Mean Number of Hops  for Backup Paths  4.9
<s> Mean Link Length (km) 93.6 


Rede Nacional de Ensino e Pesquisa (RNP)

Topology 
RNP Topology
Reference - http://www.rnp.br/en/backbone/index.php (Accessed: Jun. 18/2009)

Parameters

Variable Description Value
N Number of  Nodes  10
L Number of Links  12
<δ> Mean Nodal Degree  2.40
<h> Mean Number of Hops  for Working Paths  2.30
<h'> Mean Number of Hops  for Backup Paths  4.10
<s> Mean Link Length (km)  747.72


Abilene Core

Topology 
ABILENE Topology
Reference - http://nic.onenet.net/technical/category5/core_topology.htm (Accessed: Jan. 15/2011)

Parameters

Variable Description Value
N Number of  Nodes  10
L Number of Links  13
<δ> Mean Nodal Degree  2.6
<h> Mean Number of Hops  for Working Paths  --
<h'> Mean Number of Hops  for Backup Paths  --
<s> Mean Link Length (km)  1067


LEARN Network

Topology 
LEARN Topology
Reference - http://tx-learn.org/about/network.aspx  (Accessed: Jan. 02/2011)

Parameters

Variable Description Value
N Number of  Nodes  10
L Number of Links  12
<δ> Mean Nodal Degree  2.4
<h> Mean Number of Hops  for Working Paths  2.3
<h'> Mean Number of Hops  for Backup Paths  4.8
<s> Mean Link Length (km)  189


Science Information Network, (SINET)

Topology 
vBNS Topology
Reference - http://www.sinet.ad.jp/Network/domestic2.jpg   (Accessed: Jan. 02/2011)

Parameters

Variable Description Value
N Number of  Nodes  11
L Number of Links  13
<δ> Mean Nodal Degree  2.36
<h> Mean Number of Hops  for Working Paths  --
<h'> Mean Number of Hops  for Backup Paths  --
<s> Mean Link Length (km)  277


CompuServe

Topology 
 Compuserve Topology
Reference - http://www.nthelp.com/images/compuserve.jpg (Accessed: Apr. 22/2013)

Parameters

Variable Description Value
N Number of  Nodes  11
L Number of Links  14
<δ> Mean Nodal Degree  2.55
<h> Mean Number of Hops  for Working Paths  --
<h'> Mean Number of Hops  for Backup Paths  --
<s> Mean Link Length (km) 1161 


The Very-High Performance Backbone Network Service (vBNS)

Topology 
vBNS Topology
Reference - http://www.stanford.edu/services/internet2/vbns.html  (Accessed: Jun. 18/2009)

Parameters

Variable Description Value
N Number of  Nodes  12
L Number of Links  17
<δ> Mean Nodal Degree  2.83
<h> Mean Number of Hops  for Working Paths  2.40
<h'> Mean Number of Hops  for Backup Paths  3.90
<s> Mean Link Length (km)  965


Czech Education and Scientific Network (CESNET)

Topology 
CESNET Topology
Reference - http://www.cesnet.cz/provoz/zatizani   (Accessed: Jun. 18/2009)

Parameters

Variable Description Value
N Number of  Nodes  12
L Number of Links  19
<δ> Mean Nodal Degree  3.17
<h> Mean Number of Hops  for Working Paths  2.0
<h'> Mean Number of Hops  for Backup Paths  3.2
<s> Mean Link Length (km)  91


Australian Academic and Research Network (AARNET)

Topology 
CESNET Topology
Reference - http://www.topology-zoo.org/gallery.html   (Accessed: Jun. 18/2010)

Parameters

Variable Description Value
N Number of  Nodes  13
L Number of Links  13
<δ> Mean Nodal Degree  2.00
<h> Mean Number of Hops  for Working Paths  --
<h'> Mean Number of Hops  for Backup Paths  --
<s> Mean Link Length (km)  911


Florida LambdaRail Network (FLRNET)

Topology 
CESNET Topology
Reference - http://www.flrnet.org/?page_id=247   (Accessed: Jun. 04/2014)

Parameters

Variable Description Value
N Number of  Nodes  13
L Number of Links  14
<δ> Mean Nodal Degree  2.15
<h> Mean Number of Hops  for Working Paths  --
<h'> Mean Number of Hops  for Backup Paths  --
<s> Mean Link Length (km)  152


National Science Foundation Network (NSFNET)

Topology 
NFSNET Topology
Reference - http://www.ucpr.edu.co/paginas/revista57/auge.htm (Accessed: Jun. 18/2009)

Parameters

Variable Description Value
N Number of  Nodes  14
L Number of Links  21
<δ> Mean Nodal Degree  3.00
<h> Mean Number of Hops  for Working Paths  2.14
<h'> Mean Number of Hops  for Backup Paths  3.60
<s> Mean Link Length (km)  1086


Italy Network (ITALY)

Topology 
ITALY Topology
Reference - D. Colle et al., "Data-centric optical networks and their survivability," IEEE J. Sel. Areas Commun. 2002 (Accessed: Nov. 05/2008)

Parameters

Variable Description Value
N Number of  Nodes  14
L Number of Links  29
<δ> Mean Nodal Degree  4.14
<h> Mean Number of Hops  for Working Paths  1.9
<h'> Mean Number of Hops  for Backup Paths  2.8
<s> Mean Link Length (km)  280


Iris Education and Research Network (HEANET)

Topology 
ACOnet Topology
Reference - http://www.heanet.ie/about   (Accessed: Jun. 04/2014)

Parameters

Variable Description Value
N Number of  Nodes  15
L Number of Links  15
<δ> Mean Nodal Degree  2.00
<h> Mean Number of Hops  for Working Paths  --
<h'> Mean Number of Hops  for Backup Paths  --
<s> Mean Link Length (km)  81


Austrian Academic Computer Network (ACONET)

Topology 
ACOnet Topology
Reference - http://www.aco.net/technologie.html  (Accessed: Jun. 18/2009)

Parameters

Variable Description Value
N Number of  Nodes  15
L Number of Links  22
<δ> Mean Nodal Degree  2.53
<h> Mean Number of Hops  for Working Paths  2.2
<h'> Mean Number of Hops  for Backup Paths  3.2
<s> Mean Link Length (km)  118.67


Mzima Backbone Network (MZIMA)

Topology 
MZIMA Topology
Reference - http://www.mzima.net/gfx  (Accessed: Jun. 18/2009)

Parameters

Variable Description Value
N Number of  Nodes  15
L Number of Links  19
<δ> Mean Nodal Degree  2.53
<h> Mean Number of Hops  for Working Paths  2.8
<h'> Mean Number of Hops  for Backup Paths  5.2
<s> Mean Link Length (km)  852.11


Kiwi Advanced Research and Education Network (KAREN)

Topology 
GARR-B Topology
Reference - http://www.topology-zoo.org/gallery.html   (Accessed: Jan. 2/2011)

Parameters

Variable Description Value
N Number of  Nodes  16
L Number of Links  17
<δ> Mean Nodal Degree  2.13
<h> Mean Number of Hops  for Working Paths  --
<h'> Mean Number of Hops  for Backup Paths  --
<s> Mean Link Length (km)  189


Belgian National Research and Education Network (BELNET)

Topology 
GARR-B Topology
Reference - http://www.topology-zoo.org/gallery.html   (Accessed: Jan. 2/2011)

Parameters

Variable Description Value
N Number of  Nodes  16
L Number of Links  18
<δ> Mean Nodal Degree  2.25
<h> Mean Number of Hops  for Working Paths  --
<h'> Mean Number of Hops  for Backup Paths  --
<s> Mean Link Length (km)  49


Indian Education and Research Network (ERNET)

Topology 
GARR-B Topology
Reference - http://www.topology-zoo.org/gallery.html   (Accessed: Jan. 2/2011)

Parameters

Variable Description Value
N Number of  Nodes  16
L Number of Links  18
<δ> Mean Nodal Degree  2.25
<h> Mean Number of Hops  for Working Paths  --
<h'> Mean Number of Hops  for Backup Paths  --
<s> Mean Link Length (km)  619


Italian Academic and Research telecommunication network (GARR-B)

Topology 
GARR-B Topology
Reference - http://www.garr.it/eng/index.php  (Accessed: Jan. 2/2011)

Parameters

Variable Description Value
N Number of  Nodes  16
L Number of Links  27
<δ> Mean Nodal Degree  3.37
<h> Mean Number of Hops  for Working Paths  2.2
<h'> Mean Number of Hops  for Backup Paths  3.85
<s> Mean Link Length (km)  224


Slovenia Academic and Research Network (ARNES)

Topology 
ARNES Topology
Reference - http://www.arnes.si/backbone.htm  (Accessed: Jun. 18/2009)

Parameters

Variable Description Value
N Number of  Nodes  17
L Number of Links  20
<δ> Mean Nodal Degree  2.35
<h> Mean Number of Hops  for Working Paths  3.0
<h'> Mean Number of Hops  for Backup Paths  6.7
<s> Mean Link Length (km)  38


Germany Network (GERMANY)

Topology 
GERMANY Topology
Reference - C.T. Politi et al., "Integrated design and operation of a transparent optical network: a systematic approach to include physical layer awareness and cost function", Comm. Magazine IEEE, 2007.

Parameters

Variable Description Value
N Number of  Nodes  17
L Number of Links  26
<δ> Mean Nodal Degree  3.06
<h> Mean Number of Hops  for Working Paths  2.7
<h'> Mean Number of Hops  for Backup Paths  4.1
<s> Mean Link Length (km)  143.1


RedIRIS (SPAIN)

Topology 
RedIRIS Topology
Reference - http://www.rediris.es/red (Accessed: Jun. 18/2009)

Parameters

Variable Description Value
N Number of  Nodes  17
L Number of Links  28
<δ> Mean Nodal Degree  3.29
<h> Mean Number of Hops  for Working Paths  2.20
<h'> Mean Number of Hops  for Backup Paths  3.40
<s> Mean Link Length (km)  319.43


California Research and Education Network (CALREN)

Topology 
CALREN Topology
Reference - http://www.cenic.org/page_id=66/  (Accessed: Jun. 04/2014)

Parameters

Variable Description Value
N Number of  Nodes  19
L Number of Links  22
<δ> Mean Nodal Degree  2.32
<h> Mean Number of Hops  for Working Paths  --
<h'> Mean Number of Hops  for Backup Paths  --
<s> Mean Link Length (km)  113


LambdaRail Network

Topology 
LAMBDARAIL Topology
Reference - http://noc.nlr.net (Accessed: Jun. 18/2009)

Parameters

Variable Description Value
N Number of  Nodes  19
L Number of Links  23
<δ> Mean Nodal Degree  2.42
<h> Mean Number of Hops  for Working Paths  3.50
<h'> Mean Number of Hops  for Backup Paths  7.00
<s> Mean Link Length (km)  671.40


Memorex Network (MEMOREX)

Topology 
MEMOREX Topology
Reference - http://www.memorex-telex.cz/products02.php   (Accessed: Jun. 18/2009)

Parameters

Variable Description Value
N Number of  Nodes  19
L Number of Links  24
<δ> Mean Nodal Degree  2.53
<h> Mean Number of Hops  for Working Paths  3.3
<h'> Mean Number of Hops  for Backup Paths  6.6
<s> Mean Link Length (km)  137.26


Canada's Advanced Metwork (CANARIE)

Topology 
CANARIE Topology
Reference - http://www.canarie.ca/canet4/connected/map.html  (Accessed: Jun. 18/2009)

Parameters

Variable Description Value
N Number of  Nodes  19
L Number of Links  26
<δ> Mean Nodal Degree  2.74
<h> Mean Number of Hops  for Working Paths  3.0
<h'> Mean Number of Hops  for Backup Paths  5.3
<s> Mean Link Length (km)  667.82


European Optical Network (EON)

Topology 
EON Topology
Reference - M. Klinkowski et al., "Adaptative routing algorithms for optical packet switching networks," ONDM 2005.

Parameters

Variable Description Value
N Number of  Nodes  19
L Number of Links  37
<δ> Mean Nodal Degree  3.89
<h> Mean Number of Hops  for Working Paths  2.3
<h'> Mean Number of Hops  for Backup Paths  3.2
<s> Mean Link Length (km)  753.76


ARPANET

Topology 
ARPANET Topology
Reference - http://www.optical-network.com/topology.php (Accessed: Jun. 18/2009)
Parameters

Variable Description Value
N Number of  Nodes  20
L Number of Links  32
<δ> Mean Nodal Degree  3.20
<h> Mean Number of Hops  for Working Paths  2.80
<h'> Mean Number of Hops  for Backup Paths  4.10
<s> Mean Link Length (km)  839.14


optosunet (SWEDEN)

Topology 
OPTOSUNET Topology
Reference - http://basun.sunet.se/aktuellt/optosunetbroschyr_eng.pdf (Accessed: Jan. 02/2011)

Parameters


Variable Description Value
N Number of  Nodes  20
L Number of Links  24
<δ> Mean Nodal Degree  2.4
<h> Mean Number of Hops  for Working Paths  3.7
<h'> Mean Number of Hops  for Backup Paths  7.3
<s> Mean Link Length (km)  100


Hibernia USA

Topology 
Hibernia Topology
Reference - http://www.hiberniaatlantic.com/US_network.html (Accessed: Apr. 22/2013)

Parameters

Variable Description Value
N Number of  Nodes  20
L Number of Links  27
<δ> Mean Nodal Degree  2.70
<h> Mean Number of Hops  for Working Paths  --
<h'> Mean Number of Hops  for Backup Paths  --
<s> Mean Link Length (km) 279 


Polish Optical Internet Network (PIONIER)

Topology 
PIONIER Topology
Reference - http://www.pionier.gov.pl/network  (Accessed: Jun. 18/2009)

Parameters

Variable Description Value
N Number of  Nodes  21
L Number of Links  25
<δ> Mean Nodal Degree  2.38
<h> Mean Number of Hops  for Working Paths  3.3
<h'> Mean Number of Hops  for Backup Paths  6.6
<s> Mean Link Length (km)  131.39


Cox High Speed Internet Backbone (COX)

Topology 
COX Topology
Reference - http://www.coxbusiness.com/value/lalaunch/images/mapNationalInt.gif (Accessed: Jun. 18/2009)

Parameters

Variable Description Value
N Number of  Nodes  24
L Number of Links  40
<δ> Mean Nodal Degree  3.33
<h> Mean Number of Hops  for Working Paths  2.72
<h'> Mean Number of Hops  for Backup Paths  4.40
<s> Mean Link Length (km)  662.10


Slovak Academic Network (SANET)

Topology 
SANET Topology
Reference - http://www.sanet.sk/en/siet_topologia.shtm  (Accessed: Jun. 18/2009)

Parameters

Variable Description Value
N Number of  Nodes  25
L Number of Links  28
<δ> Mean Nodal Degree  2.24
<h> Mean Number of Hops  for Working Paths  4.6
<h'> Mean Number of Hops  for Backup Paths  9.6
<s> Mean Link Length (km)  35.84


Finnish University and Research Network (FUNET)

Topology 
FUNET Topology
Reference - http://www.csc.fi/english/institutions/funet/about/backbone/index_html  (Accessed: Jun. 04/2014)

Parameters

Variable Description Value
N Number of  Nodes  26
L Number of Links  27
<δ> Mean Nodal Degree  2.08
<h> Mean Number of Hops  for Working Paths  --
<h'> Mean Number of Hops  for Backup Paths  --
<s> Mean Link Length (km)  106


NEWNET

Topology 
NEWNET Topology
Reference - https://wiki.internet2.edu/confluence/display/I2RevDoc/Architecture (Accessed: Nov. 05/2008)

Parameters

Variable Description Value
N Number of  Nodes  26
L Number of Links  31
<δ> Mean Nodal Degree  2.38
<h> Mean Number of Hops  for Working Paths  4.23
<h'> Mean Number of Hops  for Backup Paths  7.30
<s> Mean Link Length (km)  528.14


Portugal Network (PORTUGAL)

Topology 
PORTUGAL Topology
Reference - J. Pedro et al., "On a portuguese backbone network of reference, " SEON 2005. 

Parameters

Variable Description Value
N Number of  Nodes  26
L Number of Links  36
<δ> Mean Nodal Degree  2.77
<h> Mean Number of Hops  for Working Paths  2.5
<h'> Mean Number of Hops  for Backup Paths  5.0
<s> Mean Link Length (km)  203.3


National Telecommunication Network for Technology, Education and Research (RENATER)

Topology 
RENATER Topology
Reference - http://www.renater.fr/spip.php?rubrique12\〈=en  (Accessed: Jun. 18/2009)

Parameters

Variable Description Value
N Number of  Nodes  27
L Number of Links  35
<δ> Mean Nodal Degree  2.59
<h> Mean Number of Hops  for Working Paths  3.3
<h'> Mean Number of Hops  for Backup Paths  6.0
<s> Mean Link Length (km)  154.8


Italian Backbone Network (IBN31)

Topology 
IBN31 Topology
Reference - http://dx.doi.org/10.1364/NFOEC.2012.JTh2A.37 (Accessed: Apr. 22/2013)

Parameters

Variable Description Value
N Number of  Nodes  33
L Number of Links  51
<δ> Mean Nodal Degree  3.29
<h> Mean Number of Hops  for Working Paths  --
<h'> Mean Number of Hops  for Backup Paths  --
<s> Mean Link Length (km) 131 


Geant Backbone Topology (GEANT2)

Topology 
GEANT2 Topology
Reference - http://www.geant2.net/server/show/nav.00d007009  (Accessed: Jun. 18/2009)

Parameters

Variable Description Value
N Number of  Nodes  32
L Number of Links  52
<δ> Mean Nodal Degree  3.25
<h> Mean Number of Hops  for Working Paths  3.3
<h'> Mean Number of Hops  for Backup Paths  5.0
<s> Mean Link Length (km)  661.45


Louisiana Optical Network Initiative (LONI)

Topology 
LONI Topology
Reference - http://www.loni.org/images/LONI\_Architecture\_060106.jpg  (Accessed: Jun. 18/2009)

Parameters

Variable Description Value
N Number of  Nodes  33
L Number of Links  37
<δ> Mean Nodal Degree  2.24
<h> Mean Number of Hops  for Working Paths  5.6
<h'> Mean Number of Hops  for Backup Paths  13.2
<s> Mean Link Length (km)  62.16


Metrona Network (METRONA)

Topology 
METRONA Topology
Reference - http://www.metronap.net/Network-Map.aspx (Accessed: Jun. 18/2009)

Parameters

Variable Description Value
N Number of  Nodes  33
L Number of Links  41
<δ> Mean Nodal Degree  2.48
<h> Mean Number of Hops  for Working Paths  5.17
<h'> Mean Number of Hops  for Backup Paths  8.90
<s> Mean Link Length (km)  73.4


Global Communication Net AD (BULGARIA)

Topology 
BULGARIA Topology
Reference - http://www.gcn.bg/bg_backbone.html (Accessed: Jan. 02/2011)

Parameters

Variable Description Value
N Number of  Nodes  32
L Number of Links  33
<δ> Mean Nodal Degree  2.06
<h> Mean Number of Hops  for Working Paths 
<h'> Mean Number of Hops  for Backup Paths 
<s> Mean Link Length (km)  51.17


COST37

Topology 
COST37 Topology
Reference - http://ars.els-cdn.com/content/image/1-s2.0-S1573427710000160-gr2.jpg (Accessed: Apr. 20/2013)

Parameters

Variable Description Value
N Number of  Nodes  37
L Number of Links  57
<δ> Mean Nodal Degree  3.08
<h> Mean Number of Hops  for Working Paths  --
<h'> Mean Number of Hops  for Backup Paths  --
<s> Mean Link Length (km) 439  


CERNET

Topology 
 CERNET Topology
Reference - http://www.edu.cn/introduction_1378/20060323/t20060323_158657.shtml (Accessed: Apr. 22/2013)

Parameters

Variable Description Value
N Number of  Nodes  37
L Number of Links  53
<δ> Mean Nodal Degree  2.86
<h> Mean Number of Hops  for Working Paths  --
<h'> Mean Number of Hops  for Backup Paths  --
<s> Mean Link Length (km) 636  


Omnicom Telecommunications Network (OMNICOM)

Topology 
OMNICOM Topology
Reference - http://www.omnicom-telecom.com/company.html (Accessed: Jun. 18/2009)

Parameters

Variable Description Value
N Number of  Nodes  38
L Number of Links  54
<δ> Mean Nodal Degree  2.84
<h> Mean Number of Hops  for Working Paths  4.50
<h'> Mean Number of Hops  for Backup Paths  7.30
<s> Mean Link Length (km)  298


Internet2 Network (INTERNET2)

Topology 
INTERNET2 Topology
Reference - http://www.internet2.edu/pubs/networkmap.pdf/ (Accessed: Jun. 18/2009)

Parameters

Variable Description Value
N Number of  Nodes  56
L Number of Links  61
<δ> Mean Nodal Degree  2.18
<h> Mean Number of Hops  for Working Paths  8.60
<h'> Mean Number of Hops  for Backup Paths  15.10
<s> Mean Link Length (km)  334.27


CORONET

Topology 
 CORONET Topology
Reference - http://monarchna.com/topology.html (Accessed: Apr. 22/2013)

Parameters

Variable Description Value
N Number of  Nodes  75
L Number of Links  99
<δ> Mean Nodal Degree  2.64
<h> Mean Number of Hops  for Working Paths  --
<h'> Mean Number of Hops  for Backup Paths  --
<s> Mean Link Length (km) 326  


Korotky's Prototypical Backbone Network (USA)

Topology
USA Topology
Reference - S. Korotky, Network Global Expectation Model: A Statistical Formalism for Quickly Quantifying Network Needs and Costs, IEEE/OSA J. Lightw. Technol., 2004.

Parameters

Variable Description Value
N Number of  Nodes  100
L Number of Links  171
<δ> Mean Nodal Degree  3.42
<h> Mean Number of Hops  for Working Paths  6.60
<h'> Mean Number of Hops  for Backup Paths  8.60
<s> Mean Link Length (km)  310.39




The following papers have acknowledged the use of this repository of optical transport network topologies:


  1. C. Pavan, R. M. Morais, J. R. F. da Rocha, and A. N. Pinto, “Generating realistic optical transport network topologies,” IEEE/OSA Journal of Optical Communication and Networking, Vol. 2, No. 1, pp. 80–90, Jan. 2010.
  2. R. M. Morais, C. Pavan, C. Requejo, and A. N. Pinto, “Genetic algorithm for the topological design of survivable optical transport networks,” IEEE/OSA Journal of Optical Communication and Networking, Vol. 3, No. 1, pp. 17–26, Jan. 2011.
  3. A. N. Pinto, C. Pavan, and R. M. Morais, “Dimensioning optical networks: A practical approach,” Proc. of International Conf. on Transparent Networks (ICTON), Munich, Germany, pp. 1-4, June 2010 .
  4. S. K. Routray, R. M. Morais, J. R. F. da Rocha, and A. N. Pinto, “Statistical Model for Link Lengths in Optical Transport Networks,” IEEE/OSA Journal of Optical Communication and Networking, Vol. 5, No. 7, July 2013.
  5. S. K. Routray, G. Sahin, J. R. F. da Rocha, and A. N. Pinto, “Estimation of Link-Dependent Parameters in Optical Transport Networks from Statistical Models,” IEEE/OSA Journal of Optical Communication and Networking, Vol. 6, No. 6, June 2014.
  6. S. K. Routray, J. R. F. da Rocha, and A. N. Pinto, “Estimating the Parameters of Optical Transport Networks from their Circumferential Ellipses,” Proc. of IEEE International Conference on Telecommunications, Lisbon, May 2014.