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To evaluate residents in North China cognition level of iodine nutrition and their intention to evaluate individual iodine status.From February 2019 to June 2020, randomly selected six provinces and cities in north China and more than three cities or areas, then randomly selected local investigators and distributed questionnaires to urban and rural residents. The questionnaire was divided into three parts: basic information, iodine nutrition knowledge, iodine status evaluation demand and approaches.Finally, there are 740 questionnaires were included. The scores of iodine knowledge of the subjects were generally low, about 71.22% of the subjects with less than 6 points(full score of 12 points). Residents who did not know how to choose the type of salt accounted for 25.14%. Provinces and cities with low utilization rate of iodized salt(Tianjin, Shandong) had higher requirements for salt use guidance and iodine status evaluation. The awareness rate of the subjects to the harm of iodine deficiency was low(34.46%), especially the hazard to pregnant women and infants(7.57%, 4.59%). Subjects had a high demand for using wechat mini-program or kit to evaluate individual iodine nutrition(87.45%, 89.39%).At present, residents in North China have a low cognitive level of iodine nutrition, which lead to them the doubts when choosing salt types. The selection of iodized salt can be effectively guided by propagating iodine nutrition knowledge and promoting accurate iodine nutrition evaluation.

The migration and transformation of sulfur is closely related to carbon sources. However, knowledge on the co-occurrence patterns of sulfur-related bacteria and other carbon-consuming microorganisms in constructed wetlands (CWs) is limited. In this study, CWs with intertidal wetland sediments (IWS), as microbial inoculant, was constructed to investigate the sulfate and chemical oxygen demand (COD) removal rates, microbial community composition, and co-occurrence network. IWS-enhanced CWs planted with Phragmites australis (PA+) and unplanted ones (CT+) were set up with controls (PA and CT). Results showed that the sulfate removal rate was higher in PA+ (60.60% ± 0.80%) than PA (44.64% ± 2.72%). The sulfate removal rate decreased and that of COD increased in PA+ and PA when the influent sulfate concentrations were raised. Microbial analysis indicated that the numbers of sulfate-reducing bacteria (SRB), sulfur oxidizing bacteria (SOB), and carbon-degrading bacteria improved the removal efficiency of sulfate in PA+ and CT+. The microbial topological pattern revealed that the exchange of matter, energy, and information by microorganisms in PA+ and CT+ was faster than that in PA and CT. The co-occurrence network analysis indicated that SRB (e.g., unclassified Desulfuromonadaceae) harbored negative correlations with denitrifying bacteria (e.g., Thauera, Flavobacterium, and unclassified Burkholderiaceae) because of electron donor competition. However, Flavobacterium and Thauera could cooperate to denitrify through different electron donors to avoid competition. Moreover, Pseudomonas and Amaricoccus had cross-feeding and cooperation in the network when carbon was restricted.

This paper presents some instantiations of novel application-aware network architectures for emerging IT services and future Internet applications. It proposes and analyses network architectures where the Control and Service Planes are closely and seamlessly interacting with the applications. One instantiation, the Grid-GMPLS (G^2MPLS, as defined by the Phosphorus project) is presented, which implements the Network Control Plane (NCP) architecture for the support of Grid Network Services (GNS). The GNS allows the provisioning of network and HPC/Grid resources in a single-step through a set of seamlessly integrated procedures. In a second example of instantiation, a quite popular application in signalling, i.e. the Session Initiation Protocol (SIP), is integrated with the Optical Burst Switched (OBS) network technology. The SIP-enabled OBS network can be used to manage application sessions and provide network and IT services according to application requirements. This paper investigates the requirements that these new integrated architectures impose on supporting network Control and Service Planes, and technologies, and discusses their possible implementations.

A fiber Bragg grating (FBG) wavelength shift demodulation method based on tunable distributed feedback laser diode (DFB-LD) is proposed. A highly effective algorithm is proposed to demodulate the strain of the sensing FBG, which is scanned by the tunable DFB-LD. The system is unique in that accurate demodulation can be achieved by scanning only a 0.4-nm bandwidth FBG spectrum instead of relying on scanning the FBG’s principal power peak and the scanned spectrum can be any part of the FBG. Thus, the demodulation system is much more simplified in comparison to a traditional demodulation system, which enables using wavelength-division multiplexing for the FBG sensing network. With the strain experiment of the FBG, the results match the theory of the proposed demodulation method very well, and the errors of the strain experiment are within 2 pm. The tunable DFB-LD is based on reconstruction-equivalent chirp (REC) technology. The REC technology potentially offers a low-price, compact, and high-performance solution for the demodulation.

The paper presents the architecture, implementation and evaluation of the flexible and finely granular Time Shared Optical Network (TSON) metro node. It focuses on the FPGA-based Layer 2 TSON metro node system. The experimentally measured results show exceptional performance of up to 8.68 Gbps throughput per 10 Gbps port, 95.38% of theoretical maximum throughput, latency of less than 160 μsec and jitter of less than 25 μsec. The TSON topology agnostic node/network also delivers differentiated QoS latency levels yet always guaranteed (contention-free) by deploying diverse time-slice allocation schemes.

Network operators want to deliver multiple services to the end customers. This leads to the need of efficient transport of data using optical network technologies. OBS is a promising technology for metro networks, where the operator can locate their servers to provide services such as video, backup or PC virtualization. These services are competing for shared network bandwidth when running in parallel. This work develops an FPGA-based access edge node, which operates with multiple QoS applications. This paper describes the architecture of the design as well as the behaviour of the implemented solution.

An adaptive gridless OXC is implemented using a 3D-MEMS optical backplane plus optical modules (sub-systems) that provide elastic spectrum and time switching functionality. The OXC adapts its architecture on demand to fulfill the switching requirements of incoming traffic. The system is implemented in a seven-node network linked by installed fiber and is shown to provide suitable architectures on demand for three scenarios with increasing traffic and switching complexity. In the most complex scenario, signals of mixed bit-rates and modulation formats are successfully switched with flexible per-channel allocation of spectrum, time and space, achieving over 1000-fold bandwidth granularity and 1.5 Tb/s throughput with good end-to-end performance.

A novel Software/Hardware defIned NEtwork (SHINE) framework for future optical network is proposed in this paper. An FPGA based SHINE adaptive network element (SANE) carrying time shared optical network (TSON) service and 10G Ethernet service is implemented. A cross-platform C++/Qt based SHINE IDE incorporating fine/coarse granular instruction set is developed to simply compose node/network manually or automatically. Five types of SHINE working flows, i.e. node on demand, network on demand, node self-adaptation, node generation, and network generation, are depicted, then demonstrated and selectively evaluated. Particularly, a hitless switch-over between sub-wavelength service (TSON) and low latency fat pipe service (10G Ethernet) (network on demand), and a receiver automatically detects transmitter's change (i.e. switch-over from TSON to Ethernet), then adjusts itself (node self-adaption), are highlighted.

The paper presents a novel network on-and-off chip approach for highly efficient and transparent intra-datacenter communications. The implemented FPGA-based network on-chip line card enables hitless adaptation between Ethernet and TSON, which is supported by a flexible network off-chip of AoD, demonstrating end-to-end high performance results.

The paper presents some results from the experimental validation of the achievements of the EU DICONET project. Specifically, the DICONET test-bed is presented and the experiments conducted for the performance evaluation of the control plane approaches designed to include the Physical layer Information (PLI) in the Routing and Wavelength Assignment (RWA) problem are discussed.

An adaptive gridless OXC is demonstrated using field fiber. The OXC adapts its architecture on demand to switch variable type signals in frequency, time and space domain with 1000-fold bandwidth granularity and 1.5 Tb/s throughput.

This paper presents a hybrid optical test-bed controlled by a hardware-accelerated control plane capable of dynamically provisioning the most suitable route according to the requirements of the client technology and the physical characteristics of the network.

This paper presents a hardware accelerated QoT estimation tool used in the DICONET impairment-aware optical network. Performance evaluation is given by examining different network scenarios in terms of network size and number of wavelengths.

This article presents a novel application- aware network architecture for evolving and emerging IT services and applications. It propos- es to enrich an optical burst switching network with a session control layer that can close the gap between application requests and network control. The session control layer is implement- ed using the Session Initiation Protocol, giving birth to what is called a SIP-OBS architecture. The article discusses the important added value of this architecture, and shows that it may sup- port a number of end-to-end resource discovery and reservation strategies (for both network and non-network resources). Finally, it presents a testbed implementation where this approach was experimentally validated.

Gigabit passive optical network (GPON) is likely to play an important role in future access networks and the current challenge is to increase the existing GPON bit-rate to 10 Gb/s to provide next generation access (NGA). However, implementing this in a cost-effective manner is difficult and an important research topic. One of the difficulties in implementation for the electronic part of high-speed GPON is the fragmentation feature as it requires multiple pipeline paths. This paper proposes a novel segmentation and reassembly (SAR) scheme, which simplifies the implementation of fragmentation in that it employs fewer FPGA resources and allows a faster hardware clock rate. Analysis confirms that the scheme does not suffer from reduced efficiency in a variety of conditions. It is also backward compatible and suitable for current 1.25 Gb/s and 2.5 Gb/s GPONs. The novel SAR is verified by both a hardware GPON emulator and a software OPNET simulation.

This paper presents multi-granular OBS node architectures able to manage multiservice traffic according to the required Quality-of-Service (QoS). These nodes exploit fast and slow switching devices to obtain scalable and cost-effective network.

This paper presents a novel solution for realization of service oriented optical networking. The solution is based on advanced optical burst switched network scenario utilizing novel service oriented optical burst switched core and edge router technologies. We demonstrate service-aware bandwidth reservation in a multi-granular OBS test-bed. We also demonstrate non-network services and data layer connections over OBS control plane by extending the JIT OBS protocol.

This paper presents an application-aware ingress interface for dynamic OBS networks. Aggregation mechanisms that consider application requirements have been simulated and experimentally demonstrated on the testbed.

This paper presents a novel application-aware network architecture for emerging IT services and future Internet applications. It proposes and analyses network architectures that integrate Session Initiation Protocol (SIP) with Optical Burst Switched (OBS) network technology in a unified manner. It demonstrates that the proposed SIP-enabled OBS network can be used to manage application sessions and provide network and IT services according to the application requirements. Furthermore, various SIP over OBS layering architectures, utilizing a number of end-to-end resource discovery protocols (both for network and non-network (IT) resources) are presented and analyzed. Finally, this paper reports on the validation of functionalities, mechanisms and protocols for the proposed SIP-enabled OBS network, from the node level to the network level, through a test-bed demonstrator.

The paper presents a novel network architecture on demand approach using on-chip and-off chip implementations, enabling programmable, highly efficient and transparent networking, well suited for intra-datacenter communications. The implemented FPGA-based adaptable line-card with on-chip design along with an architecture on demand (AoD) based off-chip flexible switching node, deliver single chip dual L2-Packet/L1-time shared optical network (TSON) server Network Interface Cards (NIC) interconnected through transparent AoD based switch. It enables hitless adaptation between Ethernet over wavelength switched network (EoWSON), and TSON based sub-wavelength switching, providing flexible bitrates, while meeting strict bandwidth, QoS requirements. The on and off-chip performance results show high throughput (9.86Ethernet, 8.68Gbps TSON), high QoS, as well as hitless switch-over.

Fast lightpath restoration becomes particularly challenging in all-optical networks. First, the optical transparency complicates failure localization and isolation procedures, as loss of light alarms stemming from a failure propagate downstream from the failure point. Besides, such a transparency implies that optical signals must traverse relatively long distances without electrical regeneration. In view of this, backup path computations must also account for all degradations introduced in the physical end-to-end path, thus ensuring their feasibility. Looking toward the optical core networks of the future, the EU DICONET Project has worked on cross-layer solutions to enhance network control and management with the impairment-awareness needed to govern the underlying optical layer. This includes a network planning and operation tool (NPOT) that implements impairment-aware routing and wavelength assignment algorithms, along with a failure localization mechanism. This paper reports the experimental demonstration of a dynamic impairment-aware restoration scheme that benefits from enhanced NPOT features for fast lightpath restoration. To this end, a prioritized scheduler to provide differentiated resilience support, the implementation of the quality of transmission estimator module on field programmable gate array hardware, and a fast resource pre-reservation protocol are presented in this work. The performance of the proposed impairment-aware lightpath restoration scheme has been evaluated experimentally on a 14-node all-optical network test-bed, showing average restoration times of 1.16 and 1.64 s for high and low priority traffic classes, respectively.

This paper presents a novel service-oriented network architecture to bridge the informational gap between user applications and optical networks providing technology-agnostic multigranular optical network services for clouds. A mediation layer (service plane) between user applications and network control is proposed to facilitate a mapping process between user application requests and the network services. At the network level, a multigranular optical network (MGON) is proposed and implemented to support dynamic wavelength and subwavelength granularities with different transport formats [optical burst switched (OBS), optical burst transport (OBT)], reservation protocols (one-way, two-way), and different quality-of-service (QoS) levels per service type. The service-oriented multigranular optical network has been designed, implemented, and demonstrated on an experimental testbed. The testbed consists of service and network resource provisioning, service abstraction, and network resource virtualization. The service-to-network interoperation is provided by means of a gateway that maps service requests to technology-specific parameters and a common signaling channel for both service and network resource provisioning.

A fundamental issue in all-optical switching is to offer efficient and cost-effective transport services for a wide range of bandwidth granularities. This paper presents multi-granular optical cross-connect (MG-OXC) architectures that combine slow (ms regime) and fast (ns regime) switch elements, in order to support optical circuit switching (OCS), optical burst switching (OBS), and even optical packet switching (OPS). The MG-OXC architectures are designed to provide a cost-effective approach, while offering the flexibility and reconfigurability to deal with dynamic requirements of different applications. All proposed MG-OXC designs are analyzed and compared in terms of dimensionality, flexibility/reconfigurability, and scalability. Furthermore, node level simulations are conducted to evaluate the performance of MG-OXCs under different traffic regimes. Finally, the feasibility of the proposed architectures is demonstrated on an application-aware, multi-bit-rate (10 and 40 Gbps), end-to-end OBS testbed.

The future optical network needs to offer dynamic bandwidth allocation with the ability to adapt to application bandwidth requirements by providing transport granularity at the appropriate bit rate. A key element in such a network is a high-speed multigranular optical router that is able to support wavelength and subwavelength switching. This paper proposes advanced switching and router technologies suitable for such a network. A generic architecture for a multigranular optical switch comprising optical wavelength switching, optical time division multiplexing, optical packet switchng, and optical burst switching is proposed followed by specific designs for each part of the multigranular switch. This includes a design for an optical time-slot switch followed by a design for optical-packet- and burst-switched core and edge routers. Finally, an example is provided to show how these technologies can be combined to provide connectivity for applications with different bandwidth granularities.