intelligent optical networks michal debski rami abielmona elg 7187 wednesday november 21, 2001 prof....
TRANSCRIPT
Intelligent Optical Networks
Michal Debski
Rami Abielmona
ELG 7187
Wednesday November 21, 2001
Prof. Dan Ionescu
Presentation Breakdown
1. Intelligent Network (IN) Breakdown
2. Optical Network (ON) Breakdown
3. IN + ON = ION
4. Features of IONs
5. Current and Future Leaders
6. Challenges and Outlook on Technology
7. Limitations and Conclusions
Introduction to intelligent networks (INs)
Service-independent telecommunications network, capable of operating and provisioning new services.
Initiated by Bellcore in USA in 1985 [1], with an initial goal of providing network operators with the ability of introducing and managing new services through a central database.
Basic concept involves the schism between the service providers and the telecommunication networks and equipment vendors, in order to seamlessly distribute and provision new services in various equipment.
Work has to be done to ensure that the generic components can easily interface to each other on different vendors’ equipment, through a published, open-interface standard.
The CCITT approved and published a more organized structure of intelligent networks in 1993, naming the entity the advanced intelligent network (AIN)
Intelligent network benefits
Rapid service introduction
Reduces latency of introducing new services throughout a network
Robust service customization
Services are adaptable and depend on the customer needs
Established vendor independence
Same equipment, different services, OR different equipment, same services
Portable open interfaces
Market is not dominated by one or two vendors, since service providers can run their products using open interfaces
Basic service is enhanced through added network intelligence
Provides for very rapid service turnover
Intelligent network concept
Intelligent peripherals remotely manage the network
Allows for a dynamic insertion of new services into the network
Intelligent network architecture
Evolution of network transmission technology1st Generation: Copper media
Slow data rates
Susceptible to noise, high loss
2nd Generation: Optical fibre, (late 80s)
Supports higher data rates
Allows for longer link lengths
Dense Wavelength-Division Multiplexing (DWDM, 1994):
Multiplexing of many data streams using different wavelengths
3rd Generation: Intelligent optical networks (1999-on)
Integrated routing and signaling for optical paths
Optics provide an underlying flexible layer to provide network services
DWDM
DWDM – Dense Wavelength Division Multiplexing
Physical layer for today’s intelligent optical networks
Multiplexes multiple waves of light onto single fibre
Able to transmit data faster and further:
10 - 40 Gb/sec per wave
160 waves per fibre
1000s km per haul w/ use of amplifiers
--> 160 * 40 Gb/sec =6.4Tb/sec
(100,000,000 simultaneous phone calls)
Accompanying Laser Technology
Flat gain semiconductor optical amplifiers (+20dBm)
Narrowband Tunable Lasers (1530nm-1565nm)
Tunable filters
Wavelength shifters
Optical cross-connects
Thin-film Substrates
Fiber Bragg Gratings
Bragg Optical Multiplexer
DWDM System Example
DWDM Optical System with Amplifiers
ITU Channel Spacing:
IONs: Merging Intelligent and Optical Networks
Ring architectures being applied to the optical network domain
Built-in network intelligence has two aspects: node-based and network-based
Aspects of intelligence in IONs
Node-based
Used to refer to the network elements’ intelligent software capable of sensing a module failure or a break in a fibre connection and automatically routing traffic in the opposite direction of the ring
Networks are currently capable of routing 40 optical signals in less than 50 milliseconds [3]
Network-based
Used to refer to the network’s capability of deploying new services without physical intervention
Main driver is Gigabit Ethernet (GE) and 10GE
“Point and configure” capabilities brought all the way to the end user increase value added, as customer is directly involved in the service definition
Advantages in IONsCentralized service control
Rapid customization and deployment of services
Remote control intervention of services
Customer intervention in service definition
Challenges in IONsCentralized ….
Classic central control problems, where if control logic is down, then service is down for the whole network
Rapid …
Rapid introduction of services could be costly from a design and testing perspective
Remote …
Security involved in allowing customers remote control has to be of the highest priority
Customer …
Increased reliance on customer feedback and telecommunication in general
Challenge: Routing and Wavelength Assignment
(RWA) The challenge is to route light paths through the network
Each light path on a link has to be of a different wavelength
Wavelength conversion allows an efficient way to route a light path through the network without collisions
Routing inefficiencies can occur in the absence of wavelength conversion
Current Implementations of IONsCurrent trend to design Opticaly Transparent Switches which feature low latency and signaling independence
Intelligent Optical Backplanes:
Provide the ability to Transport, Process and Filter Terabits of data per second
Use Dynamically Reconfigurable and Scalable Field-Programmable Smart Pixel Arrays
Scalable Architecture to provide ‘Bandwidth on Demand’
The Intelligent Optical BackplaneA switching fabric composed of an parallel array of smart pixel arrays
Smart Pixel ArrayA smart-pixel array is a two-dimensional array of optoelectronic devices that combine optical inputs and outputs with electronic processing circuitry
A field-programmable smart-pixel array (FP-SPA) is a smart-pixel array capable of having its electronic functionality dynamically programmed in the field.
Smart Pixel Array
Supports hundreds of pixels at hundreds of Mb/sec
Provides reconfiguration, packet processing, filtering, buffering, broadcasting, flow-control and error detection
Current Market Leaders
CIENA Corporation (www.ciena.com)
CoreDirector (intelligent optical networking core switch)
LightWorks (intelligent network management software)
Sycamore Networks (www.sycamorenet.com)
SN 16000 (intelligent optical switch
SILVX (software intelligence built into NMS)
Nortel Networks (www.nortelnetworks.com)
Alteon (used across networks built on independent switching platforms)
Agilent Technologies (www.agilent.com)
Future outlook (1)
Service providers are faced with the challenge of managing fast growing networks while keeping operating costs and provisioning times
The old SONET/SDH network architectures and management solutions are inappropriate for the aforementioned trend
ION provides optical cross-connects (OXCs), enabling the market demand for scalable and adaptable services
OXC Innovations
Switching capacities matching DWDM needs
Supports large mesh technologies
Software driven route management
User selectable priority levels
Standard UNI provides automatic provisioning
Figure from slide 9
Future outlook (2)
IONs will provide for ubiquitous computing architectures, as subscribers are getting used to their services
IONs also will provide for on-demand service deployment, allowing for a great reach for the Internet
Telecommunications Information Networking Architecture (TINA) is a consortium of the top telecommunications players focused on delivering services using next-generation software. Other consortiums will aid in the transition to IONs
Challenges of Today’s IONs
Currently used optical rings are not topologically flexible and not scalable.
Wavelength router-switches are more flexible and can subsume both point-to-point and ring add-drop functionalities.
Trend to switch from ring to mesh or multi-ring topologies, allowing for more flexibility and better resource allocation.
Future of IONs
Wavelengths will routed more optimally, finding the best path and then remembering it
Optical networks will use optical framing or digital wrapper technology for signaling, enabling wavelength on demand, so transmission traffic throughout the network can match the capacity.
MPS (multi-protocol lambda switching), A "data-aware" framework that will allow for subsuming connection routing and protection activities under the IP traffic-engineering framework and will provide optimum IP-WDM layer integration. Specifically, short-reach optical interfaces on terabit IP routers will connect directly with DWDM cross-connects and will allow higher-layer protocols to request/release bandwidth in an automated manner.
Limitations of IONs
Network operators and equipment vendors must be convinced before technology can be widely deployed
Software glitches, network configuration faults and the like can have dire consequences on both a network and a technology
IONs go through a series of testing and verification phases, higher in level than the usual schemes:
Functional and regression
Conformance and interoperability
Stress and performance
Alpha and beta trial
Installation and commission
Conclusions
Initiatives are being taken in order to deploy IONs as a core infrastructure for core-networks
Fixed mobile convergence is under way, where mobility systems are being married to INs in order to take advantage of the inherent network intelligence of INs
Reliability is the major concern for any optical network operator, and IONs have to be rigorously tested from the outset, in order to reach a certain comfort level
New services can be now deployed on-demand, and with minimal physical intervention. As well, IONs allow for a continuous link between the customer and the network operator
The open interfaces allow providers to run their services on numerous equipment
References
[1] Harju, Jarmo, Karttunen, Tapani and Martikainen, Olli. “Intelligent Networks”. Chapman & Hall: Cornwall, UK, 1995.
[2] Thorner, Jan. “Intelligent Networks”. Artech House: Norwood, MA, 1994.
[3] Alcatel White Paper: “Optical Networks”.
[4] Tecorida Technologies White Paper: “Intelligent Network (IN)”.
[5] Tecorida Technologies White Paper: “International Intelligent Network (IN)”.
[6] Prof. Ted Szymanski, Intelligent Optical networks Group, “Intelligent Optical Backplanes “
[7] Kumar N. Sivajaran, Tejas Networks, “Trends In Optical networks”
[8] Sorrento Networks White Paper, “Metropolitan Optical Networks”