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In this paper, we consider a multicore fiber (MCF)-enabled elastic optical network, in which certain nodes have a lower trust level than the others, and study how to provision lightpaths with considerations of the impairments and security vulnerabilities caused by intercore crosstalk. We propose attack-aware routing, spectrum, and core assignment algorithms that give priority to avoiding physical-layer...
Fragmentation in Elastic Optical Networks is an issue caused by isolated, non-aligned, and non-contiguous frequency slots that can not be used to allocate new connection request to the network, due to the optical layer restrictions imposed to the Routing and Spectrum Assignment (RSA) algorithms. To deal with this issue, several studies about Spectrum Defragmentation have been presented. In this work,...
A regional fault-tolerant restoration mechanism based on SDN is proposed for fiber communication networks. Simulation results show that this mechanism has shorter recovery time and lower restoration failure rate than other mechanism because of avoiding the occurrence of regional faults.
In order to virtualize the optical resources and support as required, software-defined optical networks (SDON) can dynamically customize the structure and function of the optical network using the software programming method according to the requirements of the users and operators. Each layer in SDON architecture has a lot of core technology. In this paper, we focus on the dynamic scheduling and optimization...
The flow aggregation scheme which aggregates a large number of finer-grained services into one large flow can save transceivers and improve spectrum efficiency. It ensures that all services in the aggregated flow have a same routing. Moreover, the spectrum allocated to all finer-grained services in the aggregated flow is continuous. Compared with independent transmission scheme which conducts the...
We present a heuristic algorithm to address the optimization problem of routing and spectrum allocation, aimed at traffic protection and restoration in an elastic optical network. The algorithm searches for working and backup disjoint paths, using the shared path protection scheme. It divides the spectrum into two partitions and prioritizes slots in one of them for backup path traffic. The way the...
A mode conversion-based crosstalk-aware routing, spectrum and mode assignment (MC-CA RSMA) algorithm is introduced in space-division multiplexing elastic optical networks (SDM-EONs) over few-mode fibers. Simulation results show the MC-CA RSMA algorithm can greatly reduce the impact of inter-mode crosstalk on network performance compared with benchmark algorithms.
In this paper, we propose a light-tree based multicast flow aggregation (LT-MFA) scheme which can achieve the cost-efficient multicast service provisioning in elastic optical datacenter networks (EDONs). Moreover, a user-cover ratio based aggregation strategy is proposed for the LT-MFA scheme. An Integer Linear Program (ILP) model and a heuristic algorithm are developed to realize the LT-MFA scheme...
To improve the local accessibility performance, some important services are usually replicated and maintained in multiple datacenters. A user can request any datacenter which hosts the required service. The traditional end-to-end path is gradually replaced by the end-to-service path. To resist the frequently occurred natural disasters or human-made faults, survivability technologies need to be deployed...
In this paper, we develop two joint routing and resource allocation algorithms for stealth and ordinary services in optical networks. The transmission of stealth service needs to be hidden in ordinary services to achieve a better performance in privacy. Two heuristic algorithms construct paths for stealth and ordinary services base on the different routing methods. The proposed algorithms improve...
We design a metric to measure the occupied holding time difference of frequency slots. With the metric, a routing and spectrum allocation algorithm in dynamic scenario is proposed to improve the network spectral utilization. Evaluation results show the proposed algorithm outperforms obviously in blocking probability.
A light trail is a unidirectional bus from a convener node to an end node. The main advantage of a light trail over a light path is that the communication channel of a light trail can be accessed by intermediate nodes providing more flexibility for traffic grooming. Several auxiliary graph models have been developed in the literature for traffic grooming in light-trail optical WDM mesh networks. These...
Increasing the number of lightpaths for protection accommodated onto an optical fibre network improves reliability of communication services. For this purpose, more optical paths can be accommodated by a spectrally efficient path assignment algorithm, while keeping spectral efficiency of the optical path higher. In this paper, we propose a joint optimization of elastic optical path allocation methods...
Cloud computing depends critically on large data centers connected by a high-speed optical network. A fault-tolerant communication scheme to handle requests for communication in such a system is essential. In this paper we have proposed an optimal approach to the problem of developing a path-protection scheme to handle communication requests in data center (DC) networks. We have formulated our problem...
We have introduced a novel metro network architecture called Ultra-Dense Wavelength Switched Network (UD-WSN) [1], which enables an even fine spectrum granularity so as to efficiently accommodate low-speed metro services (e.g., 1GE/10GE services). We evaluate the performance of this type of networks with spectrum defragmentation and partial optical transport network (OTN) switching. An efficient spectrum...
We investigate the problem of data-intensive vNF service chain (vNF-SC) orchestration in inter-datacenter EONs. After analyzing the NP-hardness of this problem, we solve it in a sequential manner by optimizing both the request serving sequence and the data-intensive vNF-SC orchestration. Specifically, we propose a request sorting algorithm and a data-intensive vNF-SC orchestration algorithm based...
An optical network, like any system, has to be observable before it can become subject to optimization. This is the main capability that the ORCHESTRA project introduces. ORCHESTRA's high observability relies on information provided by the coherent transceivers that can be extended, almost for free, to operate as software defined optical performance monitors (soft-OPM). Monitoring information is processed...
Erasure coding has been widely adopted by data center networks, where the data is encoded and stored in multiple locations. Therefore, an efficient data retrieval service is needed to transfer encoded data from replicated stored nodes to a single destination. Elastic Optical Networks are a promising backbone technology for data center communication due to their capability to efficiently and flexibly...
Spectrum-sliced elastic optical path networks (SLICE) enable flexible bandwidth provisioning, which allows efficient resource utilization and support to heterogeneous bandwidth demands. This makes SLICE a very promising networking architecture. In SLICE, finding a route and a slice of the spectrum is an important design problem, which is known as the Routing and Spectrum Assignment (RSA) problem....
Internet traffic is generated by a multitude of applications, each one with diverse service requirements in terms of bandwidth, latency, reliability, etc. Today traffic engineering techniques can provide service differentiation at the IP/MPLS layer, but not at the optical layer. In this paper we propose a framework where application service requirements drive a dynamic multi-layer (IP/MPLS and optical)...
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