All Optical Networks Samir Chatterjee & Suzanne Pawlowski Presenter: Pengfei Liu

Outline To present a general overview of optical networks; To discuss how all-optical networks can be integrated into existing and future broadband network architectures;

All-optical Current fiber networks use electronic switching and are therefore limited to electronic speeds of a few gigabits per second. For higher speeds, it is important that the signal remain photonic throughout its path. Such networks, which use optical switching and routing, are called all-optical.

Drivers for Optical Networks Internet and Web browsing. Bandwidth requirement *8 More users Response time Graphics and visualization. 2000* bit color pixels/frame & 24 frame/sec adds up to 1Gbps

Drivers for Optical Networks Medical image access and distribution. Multimedia conferencing. Video: 10-40Mbps HDTV 2-6Mpbs MPEG Broadband services to the home.

Optical Transmission System Three basic elements Light Source: infrared light- emitting diodes( LEDs ) or Injection Laser diodes( ILDs ) Transmission medium:single- mode or multimode fiber, ultra-thin glass fiber. Detector: photodiode and phototransistor

Optical fiber principles Central core, surrounded by a cladding layer, which is covered by protective jacket ray of light travels through by reflecting along the interface between the two transparent mediums.

Optical fiber principles Total Internal Reflection Total internal reflection causes the light to be guided down the fiber. Total internal reflection is directly related to the fact that the refractive index of the cladding( n1 ) is less than the refractive index of the core( n2 ). n1 < n2

Optical Networking Technology Erbium-doped fiber amplifier( EDFA ) Optical signals are regenerated electronically to overcome the attenuation inherent in the silica fiber as well as other losses due to optical components along the line.

Optical Networking Technology Wavelength division multiplexing(WDM)

All-optical networks Tree dominant types of optical networks

All-optical networks

Optical Services Network services are provided in the form of layers of various protocols.

Optical Services UNI( User Network Interface ) ON( Optical Network ) Circuits (POTS, T-1, SONET), Datagram (IP with its best-effort service) Virtual circuits (frame-relay and ATM).

Conclusion Briefly reviewed the state of the technology and possible future directions for fiber-optic networks. There’s still a long way to go.

End of Presentation