1. TTM 1: Access and core networks, advanced: “Optical access and transport networks”
Info and Intro
Autumn 2013

2. Info overview Tutors: Presentations, write name and e-mail on list
Adjunct assoc. professor Steinar Bjørnstad
Ph.D. student Raimena Veisslari
Possible Guest lecture
The students
Presentations, write name and on list
What is the area of your project work? (2-3 keywords are sufficient)
What do you know about optical networks?
Working methods in colloquiums (..discuss..)
Curriculum overview
Tentative schedule

3. Form of lectures Based on colloquium form:
Some material is presented by Steinar, Raimena and guests
Some material is presented by students .. any volunteers?
Hopefully we all learn something …
Organised as 2 X 2 hour seminars in “Arthur”, ITEM

4. Theme overview Course Info & Intro – 1 hour (Steinar)
Optical components / transmission – 2 hours (Steinar)
Transmission continued, Core & Metro networks, Optical circuit switching (OCS) – 2 hours (Steinar)
Optical Transport Network (OTN) – 3 hours (Steinar)
Carrier Ethernet switching (Raimena)
Protection switching - 3 hours (Steinar, students)
Control and Traffic management - 3 hours (Raffaelli/Cerroni)
Access networks - 3 hours (Steinar, students)
Optical burst / packet switching (OBS/OPS) - 3 hours (Steinar, students)
Repetition – Greatest hits, Steinar/Raimena
Total: 21 hours (+ repetition)

5. Tentative schedule
See web-pages

6. Curriculum / Info / Contacts
Curriculum: Conference papers and Journal articles (Mostly ready, some to be decided)
Info on web:
(Room….)
Tlf:
Raimena Veisslari

7. Intro overview Growth rates Wavelength division multiplexing (WDM)
Optical switching - circuit/wavelength - packet
Some facts/observations

8. Internet growth Moores law (CPU) Computer performance
Double performance every 18 months, from 1975->
Computer performance
Doubles every 21 months
Router performance
Optical link performance
WDM gave a period with cost reduction of two every 12 months
Internet traffic trends
Growth trends Internet versus telephone

9. Internet traffic trends1
1) Prediction made in 2000; believe the last years have not been that fast
What do you think will make the traffic grow in the future?

10. Link capacity growth trend
Example of overoptimistic prognosis:
Internet traffic forces routers to become ”wire speed”
Internet traffic > Voice traffic
(?)

11. Capacity increase in systems
Fiber based transport/core networks
Switching of high bitrates, Gb/s and Tb/s
Currently 32 Tb/s
OCF 2009
Introduction of Wavelength Division Multiplexing (WDM)
World record in lab:
2002

12. Wavelength division multiplexing
Large capacity increase in optical fibers
Makes optical networking possible/interresting
Electronic/electrooptical
Now
Optical amplifier
WDM: channels pr fiber
1 channel pr fiber
Up to
Earlier

13. Optical switches Circuit switching Wavelength conversion
Switches signals between fibers and/or wavelengths.
Wavelength conversion
To avoid collision on wavelengths (in same fiber)
Wavelength
converter
Optical crossconnect

14. Packet switching More complicated in the optical domain:
Higher speeds needed in switches
Not (currently) available technology for optical processing of headers etc.
The payload information is switched optically
Optical buffering is difficult
Optical crossconnect (with or without wavelength conversion)
Separates header and payload
Demux of WDM signals
Mux of signals to a WDM signal
Optical buffers (to handle contention on output)

15. Some key facts Optical switching:
Optical circuit switches are available
Switches fibers or wavelengths in fibers
Optical wavelength converters are not commercially widely available
Optical packet switches in labs
Optical buffers/memory is a problem
Rapid development in optical transmission:
Systems with more than 1 Tb/s are available
Higher than 30 Tb/s is demonstrated in the lab