With the rapid development of optical networks, traditional resource allocation methods face challenges raised by network services with intensive distribution and differentiated sensitivity on time delay. Based on the real-time services distribution in the network, the traffic load balancing method dynamically schedules arriving requests at the control layer and evenly distributes it to multiple servers or network links to avoid bottleneck links and achieve balanced network resource utilization and services distribution. This paper proposes a traffic load balancing method based on time/wavelength/space evaluation on the coefficient of variation in optical networks, the purpose is to solve the game relationship between time/wavelength/space resources as a multi-dimensional network scenario. It is kind of a dynamic traffic load balancing method, assessing the degree of network equilibrium according to the conditions of network resources distribution. The routing allocation scheme is optimized with parameters evaluation on statistical. The simulation results show that the proposed scheme can stabilize the blocking ratio within 15% in a normal traffic load scenario, and the relative optimization of blocking ratio is up to 27% better than that of the benchmark algorithm with time-sensitive requests.
In this paper, we propose a multi-domain quantum key pool (QKP) capacity adaptive supplement scheme based on balance between key resource and routing hop in multi-domain QKD-ON, and we conduct the simulation and evaluate the performance of the proposed scheme in terms of service blocking probability and utilization of key resource. Results show that the algorithm can reduce service blocking probability.
In data center networks (DCNs), secure multicast provisioning services are obtained from data centers and transported to multiple users in a multicast style, which requires a high demand for security. Moreover, these services are usually stored and maintained in multiple geographically dispersed data centers for more reliable and efficient access. Quantum key distribution (QKD) is a state-of-the-art technology employed to unconditionally distribute security keys, based on the principles of quantum physics. Therefore, one should pay more attention to how to efficiently distribute global quantum keys in quantum DCNs in the near future. We investigate the problem of global QKD while leveraging multicast service backups among multiple geographically distributed datacenters for secure service provisioning. A distributed subkey-relay-tree-based, secure multicast scheme is proposed and used as a basis to develop a distributed subkey-relay-tree-based secure multicast-routing and key assignment algorithm. Numerical results show that the latter can achieve higher security probability and lower consumed keys compared with the traditional routing and key assignment scheme and single-key-relay-tree-based secure multicast scheme.
In Elastic Optical Networks (EONs), elastic operations have been constrained by the assumption that an optical signal has to occupy a dedicated frequency range, with no sharing of spectrum resources with other independent optical signals. Recently, the emergence of signal overlap techniques can break this traditional constraint in theory. In this study, we fully combine the characteristics of the application signal overlap technology, summarize two factors that affect the ultimate transmission distance of an optical signal as the modulation format of the optical signal and the interval between the center frequencies of the two optical signals, and make a reasonable assumption about their correspondence. On this basis, we propose a Routing, Modulation level and Spectrum Assignment (RMSA) algorithm based on Signal overlap for EONs. The paper simulates the two strategies of the algorithm and compares them with the basic algorithm without signal overlap. The results show that it can significantly reduce the bandwidth blocking probability, especially under heavy traffic load scenario.
Inside a service function chain (SFC), traffic flow follows a certain route, namely a service function path (SFP), to travel through each service function (SF) entity. A SFP consists of several end-to-end segments, whose source and destination are named anchor node (AN). SFs are located in multiple datacenters (DCs), and inter-DC light-paths need to be provisioned between separated SFs. In this paper, we introduce geography information of optical nodes and DCs, define special geographic distance between ANs in inter-DC elastic optical networks (EONs). Then following minimal geographic distance principle, we propose a geography-based SFP provisioning solution, which contains two heuristic algorithms, named geography-based shortest path and first-fit algorithm (GSP-FF) and geography-based k-shortest paths and first-fit algorithm (GK-FF). These algorithms can compress AN selection procedure extremely in fixed time, which cost little time for the AN selection of resource allocation. And benchmark algorithm use Dijkstra shortest path calculation and first-fit FS selection to allocate IT resources in DCs and FS resources in EONs. Then GSP-FF and GKFF are proposed to provision SFPs efficiently. In our simulation, we compare our proposed algorithms with benchmark algorithm deeply on blocking probability, running time, average hops, average geographic distance, et al. under different traffic load and other simulation environment. We also analyze the trend and reason for the performance difference among these algorithms. According detailed evaluation, simulation proves that the proposed algorithms in this paper could use geographic information efficiently, and achieve lower blocking probability with lower running time compared with the benchmark algorithm.
A PANDA polarization-maintaining few-mode ring-core fiber (PM-FM-RCF) structure with two air holes around the ring core is proposed. The relative mode multiplicity factor (RMMF) is defined to evaluate the spatial efficiency of the designed PM-FM-RCF. The performance analysis and comparison of the proposed PANDA PM-FM-RCFs considering three different types of step-index profiles are detailed. Through modal characteristic analysis and numerical simulation, the PM-FM-RCF with a lower refractive index difference (Δnoi=1.5%) between the ring core and the inner central circle can support up to 16 polarization modes with large RMMF at C-band, which shows the optimum modal properties compared with the PM-FM-RCF with higher Δnoi. All the supported polarization modes are effectively separated from their adjacent polarization modes with effective refractive index differences (Δneff) larger than 10−4, which also show relatively small chromatic dispersion (−20 to 25 ps/nm/km), low attenuation (<1.4 dB/km), and small bending radius (∼8 mm) over the C-band. The designed PM-FM-RCF can be compatible with standard single-mode fibers and applied in multiple-input multiple-output-free spatial division multiplexing optical networks for short-reach optical interconnection.
In recent years, the integrated space-ground network communication system plays an increasingly important role in earth observation and space information confrontation for the civilian and military service. Their characteristic on wide coverage, which may be the only way to provide Internet access and communication services in many areas, has extensively promoted its significance. This paper discusses the architecture of integrated space-ground communication networks, and introduces a novel routing algorithm named Improved Store-and-forward Routing Mechanism (ISRM) to shorten the transmission delay in such a network. The proposed ISRM algorithm is based on store and forward mechanism, while it trying to find several alternative delay-constraint paths by building the route-related nodes encounter-probability information table and communication timing diagram. Simulation is conducted at the end, and comparisons between ISRM and baseline algorithm are given. The results show that ISRM can achieve relatively good performance in terms of transmission latency in integrated space-ground networks.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.