A display device and a method for driving the same are disclosed. The display device confirms whether display data applied to a display panel are uniformly maintained for a predetermined time. As a result of confirmation, if the display data are uniformly maintained for a predetermined time, pixels of the display panel are made for a predetermined block unit so that screen save modes are performed to sequentially apply screen save mode data to pixels of each block. The screen save modes are completed after there are sequentially performed for all blocks on the display panel. Thus, uniform luminance deviation can be obtained on the display panel of the display device and further picture quality of the display device can be improved.

Display device and method for driving the same

This paper performs further improvement to a distributed algorithm for solving linear algebraic equations via multi-agent networks recently developed by Mou et al. , in which all agents’ states converge exponentially fast to the same solution to a group of linear equations by assuming each agent knows only part of the linear equations and its nearby neighbors’ states. We first prove that the algorithm proposed by Mou et al. with special initialization is able to achieve the solution that is closest to a given point in the Euclidean distance. Second, we eliminate the required initialization step used by Mou et al. by a modification to the update equation. Both analytical and numerical results are provided for validation.

Improvement of a Distributed Algorithm for Solving Linear Equations

Feedback fiber delay lines and AWG based optical packet switch architecture

This paper presents the TSON metro mesh network architecture for guaranteed, statistically-multiplexed services. It proposes tunable time-wavelength assignment, one-way tree-based reservation and node architecture. Results demonstrate high network efficiency, fast service delivery and guaranteed QoS.

/pdf/time-shared-optical-network-tson-a-novel-metro-architecture-q2qedu7tfu.pdf

Time shared optical network (TSON): A novel metro architecture for flexible multi-granular services

The bandwidth efficiency and relative costs for 100 Gb/s WDM transport and switching architectures are compared in North American and pan-European long-haul networks. The first architecture uses muxponders and ROADMs for end-to-end wavelength transport with no digital sub-wavelength grooming. The other two utilize digital OTN switching, as either a standalone OTN switch or a converged integrated WDM/switch system, to efficiently groom services onto WDM wavelengths. Results show the integrated WDM/switch architecture utilizes the fewest WDM wavelengths and client service interfaces, and an integrated WDM/switch architecture using photonic integrated circuit technology provides the lowest operational costs.

Total cost of ownership of WDM and switching architectures for next-generation 100Gb/s networks

Two architectures are proposed for a wavelength-division multiplexed optical packet switch equipped with both limited-range wavelength converters (LRWCs) and shared full-range wavelength converters (FRWCs). The FRWCs are used to overcome the performance degradation in terms of packet loss probability due to the use of LRWCs only. Two different sharing strategies of the FRWCs are considered. In the first architecture, a pool of FRWCs is shared among the arriving packets. In the second one, the sharing is only partial and the packets directed to the same output share a same pool of FRWCs. A probabilistic model is proposed to dimension the number of shared FRWCs so that the same packet loss probability of a switch equipped with only shared FRWCs is guaranteed. After introducing a cost model of the converters depending on the conversion range, we show that the architectures may allow a conversion cost savings on the order of 90%.

Cost Evaluation of Optical Packet Switches Equipped With Limited-Range and Full-Range Converters for Contention Resolution

A new wavelength converter sharing strategy for multifiber optical switches, namely shared-per-wavelength (SPW), which employs wavelength converters with fixed input wavelengths is presented. The aim is to reduce switch costs by using simpler optical components and low complexity space switching matrices. Practical implementations of both the well-known shared-per-node (SPN) and the new SPW schemes are presented, as well as the related scheduling algorithms to manage optical packet forwarding in synchronous scenario. An analytical model to evaluate blocking performance of the SPN architecture is also provided. Results show the accuracy of the model in the range of interest for switch design. The proposed architectures are compared in terms of performance and number of optical components employed. The SPW approach is shown to save a large number of semiconductor optical amplifier gates with respect to the SPN one when the number of fibers per interface is suitably not too high. In these cases, the SPW architecture requires a number of wavelength converters higher than the SPN, but simpler, being their inputs tuned on a single wavelength.

Multifiber Shared-Per-Wavelength All-Optical Switching: Architectures, Control, and Performance

A packet switching node is coupled by links to other nodes of a network, and receives and assembles (74) packets belonging to a specified packet flow, into bursts of packets with a burst control packet indicating a sequence of the burst in the flow. The node determines (78) whether to distribute the flow across several links. If so, the bursts are then forwarded (80) for switching to the output ports (160) of the selected links. Distributing the flow over multiple links can enable more flexible and efficient filling of allocated bandwidth on links, as traffic increases. To reduce the risk of losing the order of packets the sequence of the bursts is indicated for use in reordering at intermediate nodes during transmission through the network.

Switching node with load balancing of bursts of packets

The development of a new generation of photonic integrated circuits and the constant progress in integrated electronics (following Moore's law) made the realization of a new type of optical transport node possible, by basing it on the concept of a digital photonic switching layer working in coordination with the packet switching layer under the control of a multi-layer control plane. In this paper such a new type of optical transport node is presented, analyzed and implemented in order to better investigate its potential advantages and weaknesses if compared with the conventional all-optical transport nodes and their level of applicability. The new node concept is based on a “vertical” view of packet-opto networks able to face the challenge of growing network capacity while cutting costs and to allow an efficient combination of digital optical networks and packet-opto integration's benefits. Thanks to the use of optical-electrical-optical conversion technology, the wavelength division multiplexed (WDM) layer is provided with the traffic management flexibility and the engineering simplicity of digital transport systems (significant operational expenditures reduction) and with the network cost savings of large-scale photonic integration (capital expenditures reduction). It combines packet and WDM switching technologies where appropriate, with the ability to offload pass-through traffic from the packet layer to the lowest possible layer, so as to reduce costs and power consumption by eliminating unnecessary packet processing (total cost of ownership reduction). The main building blocks are a new digital optical transport based on an integrated packet-opto node that is scalable, flexible and low cost, and multi-layer control and management based on standard generalized multiprotocol label switching and innovative path computation element (PCE) solutions. Thanks to the flexibility of the digital reconfigurable optical add/drop multiplexer, the PCE is able to handle both layers in a very efficient way by selecting the right granularity for traffic grooming and routing. The feasibility has been assessed by a network prototype composed of four nodes produced by Ericsson Research Lab in Pisa and by a simulation analysis.

A. Germoni

Papers

Cost Evaluation of Optical Packet Switches Equipped With Limited-Range and Full-Range Converters for Contention Resolution

Multifiber Shared-Per-Wavelength All-Optical Switching: Architectures, Control, and Performance

Switching node with load balancing of bursts of packets

Packet-optical integration nodes for next generation transport networks

Packet loss analysis of shared-per-wavelength multi-fiber all-optical switch with parallel scheduling