cod. 1007803

Academic year 2021/22
1° year of course - First semester
- Annalisa MOREA
Academic discipline
Telecomunicazioni (ING-INF/03)
Attività formative affini o integrative
Type of training activity
48 hours
of face-to-face activities
6 credits
hub: PARMA
course unit

Learning objectives

Introduction to optical networking: principle and challenges.
Optical network hierarchies: core, metro and access
Introduction to the network design
Optical Transport Network (OTN)
Capacity and Flow assignment problems in communication networks
Optical switching, routers and Optical terminals
Transparent network evolution
Multilayer networks
Network survivability objectives and resiliency techniques
Automatic optical reconfiguration: from static to dynamic networks
Advantages of reconfigurable and multilayer networks
The future of optical networks: the 5G era


- Basic knowledge of programming (C, C++, Java)
- Basic knowledge of optical devices

Course unit content

Learning outcomes of the course unit:
The objective of the course is to give to the students the basis of optical network structure, operation, and management. Students will understand which are the traffic requirements and operator choices behind a network design. In particular, the following concepts will be introduced:
- Definition of OTN networks
- Routing and grooming
- Resiliency
- Optical reconfiguration
By applying the above-mentioned knowledge and the weekly practical work, the student will be able at the end of the course to:
- Design and plan optical communication networks
- Implement a planning tool
- Write a report with analysis of a network planning

Full programme

Classes are divided into two parts: theoretical and practical lessons. During the week two classes (2 hours each) of theoretical and practical lessons alternate (hereafter odd lessons relate to theoretical classes, even to practical).
Lesson 1: Introduction to the optical networking: principle and challenges.
- Enabling technologies
- Telecom network overview
- Business models
- WDM evolution

Lesson 2: Class on network planning tools. Introduction to DIAMOND.

Lesson3: Optical Cross Connects (first part)
- Description of network topologies
- Evolution of WDM transmission devices
- Description of the basic optical elements
- Definition of optical cross connects
- Introduction to optoelectronic devices
- Concept of routing in an optical network

Lesson 4: use of DIAMOND: some simple exercise.

Lesson 5: Optical Cross Connects (second part)
- O-E-O optical cross connects
- O-O-O optical cross connects
- Optical bypass
- Definition of (R-)OADM and OXC
- Add/Drop blocks
- New generation OXC requirements

Lesson 6: Git or versioning tools for managing a project.

Lesson 7: Transparent network challenges (first part)
- Opaque vs transparent routing
- Routing definition
- Optical bypass and 3R regeneration
- Description of main optical impairments
- Coherent detection
- Transparent island and selective regeneration
- Impairment based routing

Lesson 8: Introduction to the connectivity graph

Lesson 9: Transparent network challenges (second part)
- Wavelength continuity constraints
- Routing wavelength assignment (RWA) problem
- Single step and multi-step RWA + physical impairments issues
- Connectivity graph
- RWA assignment, graph coloring and conflict graph
- Mixed line rate wavelength assignment

Lesson 10: Some study with the introduction of optical reach concept and transparent islands thanks to the connectivity graph

Lesson 11: Transparent network challenges (third part)
- Flex line rate paradigm
- Routing and spectrum assignment (RSA)
- Conflict graph for RSA problems
- Super-channel concept
- Elastic transponders

Lesson 12: Introduction to the connectivity graph, routing and wavelength assignment

Lesson 13: Grooming (first part)
- Traffic types and service capacity increase
- Sub-rate traffic management
- End-to-end multiplexing
- Aggregation rules
- Grooming definition
- Grooming vs aggregation

Lesson 14: Elastic optical network planning challenges.
Study of the impact of different function costs on the network planning

Lesson 15: Grooming (second part)
- Grooming switches
- OTN layer
- Grooming design rules
- Grooming and power consumption problem

Lesson 16: Traffic aggregation and grooming, different algorithms: connectivity graph vs routing and knapsack algorithms

Lesson 17: Optical recovery (first part)
- Introduction to survivability
- Failure terminology
- Service level agreement (SLA)
- Quality of Service (QoS)
- QoS and network optimization
- Service differentiation
- Resiliency definition: protection and restoration
- Multiple failure recovery
- Shared risk link group definition
- Routing constraints

Lesson 18: Network dimensioning with resiliency constraints. Introduction to failure scenarios.

Lesson 19: Optical recovery (second part)
- Optical and electrical protection scheme descriptions
- Client vs network resiliency
- Dedicated and shared protection
- Fauld dependent vs fault independent recovery
- Network protection at OTN layer
- Multiple concurrent failures

Lesson 20: Optical reconfiguration of a network; network failure and optical restoration.

Lesson 21: Dynamic optical networks
- Introduction to optical reconfigurations
- Evolution from static to dynamic networks
- Control plane and PCE definitions
- Where to place a control plane
- GMPLS-based operations
- Software defined networks

Lesson 22: Definition of the final project work; assisted code implementation on the work for the final project.

Lesson 23: Optical transport network (OTN) standard
- OTN objective
- OTN functionalities and benefits
- OTN layering description
- ODU presentation

Lesson 24: Definition of the final project work; assisted code implementation on the work for the final project (continued).


- Slides of the course will be available
- Material distributed by the lecturer

- Supporting books:
o B. Mukherjee, Optical Networks, Springer 2006
o J. Simmons, Optical Network design and planning, Springer 2014

Teaching methods

All classes will be done in tele-presence via the Teams and Elly platform. Specifically, the synchronous lessons will be followed by Teams, while the asynchronous lessons will be uploaded on Elly on the webpage of the course. During the synchronous lessons, interactions with the students are foreseen.

Theoretical lectures will use video-projection of slides. Some exercises will be solved during the lectures. Interaction with students is welcome and will be stimulated by open questions.
Some lectures describing the software used for the planning project (Net2Plan and Git) will be given in the computer lab.
Homeworks are assigned weekly.

Assessment methods and criteria

The exam consists of an individual project which has to be presented and discussed with the instructor.

The student will design an optical network by means of a numerical simulator partially developed by the student in Java language. The student can choose between two types of project: the first concerns the planning of a static network (easier project, allowing a maximum grade of 25/30), the second the planning of a dynamic network (more complex project, allowing a maximum grade of 30/30). After having chosen the type of project, each student receives a specific planning problem to solve, whose investigation will be reported in the final project report. The project is evaluated in terms of correctness, completeness, clarity of exposition. The project is graded 1-30.
To pass the exam, a minimum score of 18 is needed.

Other information

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