Optical Management System (OMS)
It can provide multiple network
management functions, including element management, service
provisioning, service assurance and customer service management. It can
provide seamless, end-to-end network management of an entire transport
network and reduce the need for manual intervention in managing
networks.
Optical Network Management System (ONMS) increases workforce
productivity and facilitates the management of fiber optic networks
with fewer technicians through fiber remote testing and accurate fiber
plant documentation. The system accurately detects and locates fiber
degradation, alerting operators and managers with the details of
faults. Measurement schedules allow network operators to assess long
term fiber performance to form the basis of efficient asset management.
It can provide multiple network
management functions, including element management, service
provisioning, service assurance and customer service management. It can
provide seamless, end-to-end network management of an entire transport
network and reduce the need for manual intervention in managing
networks.
Optical Network Management System (ONMS) increases workforce
productivity and facilitates the management of fiber optic networks
with fewer technicians through fiber remote testing and accurate fiber
plant documentation. The system accurately detects and locates fiber
degradation, alerting operators and managers with the details of
faults. Measurement schedules allow network operators to assess long
term fiber performance to form the basis of efficient asset management.
Origin of Optical Network
Telecommunication Networks build using various communication media
- Twisted pair copper wire
- Coaxial cable
- Wireless (Radio, microwave, satellite, infrared)
- Optical fiber
Optical Fiber - Properties
Advantages of Optical Fiber
- Large Bandwidth-distance product
- immunity to noise and intereference
- very low cost per unit bandwidth
- easy upgradability using WDM technology
- Tapping of signal from fiber without being detected - difficult
Disadvantages of Optical Fiber
- Optical fiber Networks have high capacity
- Can be used for providing the high bandwidth services
- Even in wireless, infrared means high bandwidth connectivity
Broadcast Optical Networks
- Optical fiber Networks have high capacity
- Can be used for providing the high bandwidth services
- Even in wireless, infrared means high bandwidth connectivity
In Broadcast Networks,
-Bandwidth of single channel - shared by all the users
-Media access using media access control protocols
-MAC protocols need to consider
-The network is high speed
-High speed network - packet transmission time
-comparable to packet propagation time
To use the available bandwidth,
- Wavelength division multiple access (WDMA)
- Time division multiple access (TDMA)
- Code division multiple access (CDMA)
Optical TDMA ,CDMA implementations
- need very short pulses (can be generated by mode locked lasers).
- Time division multiplexers/ demultiplexer requires very tight tolerance of fiber length (due to tight timing requirments).
- Encoder and decoders will require again very tight tolerance in fiber length used for delay lines.
- Dispersion - need to be taken care of WDMA.
Media access control protocols for multiple channels classification based on tunability
- Fixed transmitter fixed receivers (FTFR)
- Tunable transmitter fixed receivers (TTFR)
- Fixed transmitter tunable receiver (FTTR)
- Tunable transmitter tunable receiver (TTTR)
Strong similarity with switching networks.Virtual Topology is built over broadcast medium
Some other multihop topologies investigated in literature
- Hypercube
- Manhatten street Network ( Torus)
- Dual bus
- Ring
For MAC protocols with tunable component proposed solutions generally use
- Scheduling - a schedule for transmission and reception on the basis of statistics is computed
periodically by centralized or distributed algorithms and used for coordination.
- Pretransmission coordination using dedicated channel
Switched Network
- Uses Optical Switches
- Classified as circuit switched or packet switched .commercially emphasis on circuit switched all-optical networks
- due to near term feasibility
- also known as wavelength routed networks
These network can be used to provide virtual topology to be used by SDH,ATM or directly by IP layer.
Issues
- Estimation of condition when the reconfiguration is needed
(will be done by IP layer)
- Management algorithms for optical layer to work with limited
wavelength.
- Fault Management in Optical Layer
Other exciting things in optical Networks
- Switching techniques and architectures
- Networks architectures using devices and phenomenon based on optical nonlinearity
- Multiwavelength soliton networks
