A node-selective cross-layer service routing (NSCR) algorithm is proposed and investigated that incorporates load balancing and demonstrates the superiority and effectiveness of the proposed schemes in terms of wavelength utilization rate and service blocking rate while satisfying the diverse delay requirements of different services.
Abstract
Fine-grained optical transport networks (fgOTNs) have attracted increasing interest in recent years for their ability to deliver small-granularity services with high flexibility and efficiency. To further improve the performance of fgOTNs in delivering small-granularity services having diverse delay requirements, this paper proposes and investigates a node-selective cross-layer service routing (NSCR) algorithm. By selecting a path based on both wavelength occupation and the quantity of currently active services that can be aggregated in the last optical hop, and by selecting proper intermediate nodes to participate in fgOTN layer exchange and aggregation under service delay constraints, the service blocking rate is reduced and resource utilization is maximized. Further, a variation of the proposed NSCR scheme is investigated that incorporates load balancing by selecting a path based on wavelength occupation, currently active service routes, and the remaining bandwidth. The performance of the two schemes is evaluated under both the NSFNET and Cost239 topologies, and the results demonstrate the superiority and effectiveness of the proposed schemes in terms of wavelength utilization rate and service blocking rate while satisfying the diverse delay requirements of different services.
The development of immersive video service and large-scale cluster computing technology further expand the potential application scope of time-sensitive networks (TSN). In the delivery network for these emerging services, Ultra-Service Flows (USFs), characterized by ultra-high bandwidth and deterministic latency, have become the most representative traffic type. Therefore, the route scheduling for hybrid deployment of Regular-Service Flows (RSFs) and USF has become an unavoidable issue within a deterministic domain. However, existing research has not thoroughly investigated routing issues for the hybrid deployment of USF and RSF since the significant differences between them. To resolve this issue, a multi-objective optimization model is designed in this paper, in which three key factors are comprehensively considered: the path blocking degree of USF, the available bandwidth rate, and the end-to-end latency of RSF. Subsequently, we propose a cooperative framework where a Transformer-DRL agent, enforced by validity-constraint masking, generates high-quality initial populations to “warm start” NSGA-II. This hybrid design replaces random initialization, effectively resolving the evolutionary “cold start” issue in large-scale topologies while ensuring routing feasibility. The simulation results demonstrate that the algorithm proposed here in significantly improves performance and generalization capabilities, improving the RSF’s overall latency, the USF’s path-blocking degree, and the available bandwidth rate by 10.526%, 14.102%, and 14.286%, respectively.
Mengjie Guo, Qiang Wu, Ran Wang et al.· IEEE Transactions on Network...· 0 citations
Fifth-generation (5G) and time-sensitive networking (TSN) are widely recognized as the most promising technologies for future industrial networks. Quality of service (QoS) mapping and traffic scheduling mechanisms are critical to ensuring deterministic transmission in 5G-TSN integrated networks. However, the uncertainty of 5G air-interface delay significantly reduces the deterministic guarantee for traffic in 5G-TSN networks. A QoS mapping algorithm based on incremental mini-batch K-means++ stratified sampling (IMK-S3) is proposed to quickly and accurately determine the 5G QoS identifier (5QI) values of traffic flows, even under dynamic traffic variations. Based on this, combined with cross-layer scheduling optimization, a QoS-mapping-based no-wait latency-balanced joint scheduling (QMLB-JS) algorithm is proposed. QMLB-JS supports hold and forward buffer mechanism in DS-TT and NW-TT, and realizes accurate time-based gating management by orchestrating the time of time-triggered (TT) traffic injection into the network. Simulation results demonstrate that the proposed algorithm improves the end-to-end deterministic transmission capability of the integrated 5G-TSN network.
He Li, Shihui Duan, Fangmin Xu et al.· IEEE Open Journal of the Com...· 0 citations
The rapid evolution of beyond-5G and emerging 6G networks is driving the need for flexible, reliable, and cost-efficient virtualized Radio Access Network (vRAN) architectures capable of supporting heterogeneous services such as enhanced Mobile Broadband (eMBB), Ultra-Reliable Low-Latency Communication (URLLC), and Massive Machine-Type Communication (mMTC). Future disaggregated RAN systems are expected to rely heavily on network slicing, functional split flexibility, and optical x-haul infrastructures to support stringent performance, scalability, and availability requirements. In this paper, we present an integrated framework for reliable, slice-aware, and functional split-aware Virtual Network Function (VNF) placement with lightpath provisioning in disaggregated vRAN environments. The proposed approach maximizes mobile network operators'profit by jointly optimizing function placement and optical resource allocation under latency, processing, bandwidth, and availability constraints. We formulate the problem as an Integer Linear Programming (ILP) model with two variants: one that employs unshared backups and another that uses a more cost-efficient shared backup scheme. To address ILP complexity, we develop a heuristic algorithm and a Genetic Algorithm (GA)-based metaheuristic that yields near-optimal solutions in real time. Extensive evaluations on topologies up to 128 nodes show that shared backup variants yield up to 18% higher profit, while maintaining up to 5-10% lower normalized CPU usage than unshared counterparts.
Mayank Ramnani, Shasank Dixit, Sushil K. Yadav et al.· 0 citations
The integrated satellite-terrestrial networks (STNs) aim to provide ubiquitous connectivity and support various services with diverse requirements. Each service request has to go through a sequence of virtual network functions (VNFs) that should be mapped on its routing path. The STNs are equipped with limited communication and computation resources, making it challenging to enable heterogeneous services. Furthermore, the movement of satellites causes frequent changes in topology, which can impact the continuity of long-lasting requests. For requests lasting multiple time frames, the VNF mapping update and path recomputation at the beginning of each time frame is computationally expensive and can cause unwanted service interruptions. Therefore, we propose a selective handover strategy where the path recomputation and VNF remapping are done only if there is a change in the previous routing path. The selective handover strategy ensures that only critical handovers are carried out while discouraging unnecessary reconfigurations, which result in service discontinuity. We develop a software-defined networking (SDN) based experimental testbed that allows us to realistically consider the system constraints. The VNF mapping and path computation for a request are done in a proactive manner, and the rate meters are installed on the switches according to the current network traffic to efficiently utilize the available bandwidth. The simulation results certify that the proposed strategy reduces the packet loss by up to 11.5% and 18.5% as compared to the benchmark schemes and provides stable throughput for eMBB services with minimal service-level agreement (SLA) violations, while also ensuring the latency requirements of mMTC.
Muhammad Ahsan, T. Vu, Ilora Maity et al.· International Mediterranean...· 0 citations
The development of sixth-generation (6G) mobile communications aims to deliver super-fast connections at terahertz frequencies, surpassing those of 5G. Nonetheless, these improvements come with challenges of data leakage and packet misinsertion, and they place greater pressure on secure and efficient routing. An Energy Optimized Network Route Cluster Bandwidth (EONRCB) is an Enhanced Service Data Transmission (ESDT) model proposed in this paper to circumvent these problems. The model contains several significant factors, such as Transmission Node Support Weight (TNSW), which evaluates network traffic and petite access control, which provides packet fragmentation and a secure route. Then, the Service Level Route Count Rollback Node Aggregator (SLR-CRNA), which validates active route node interaction. Further, the Sleeper Node Controller improves the consistency of node operations, whereas Slicing Neighbour Node Path Routing (SN2PR) introduces consistency in the source-to-destination connectivity within edge networks. Additional optimisation can be achieved through functionality such as Priority Cycle Tags (PCT) and Recursive Scheduling Time (RST), which provide mechanisms to improve overall RTPS throughput and node scheduling by minimising latency via a depth-first task alignment scheme. The suggested architecture achieves higher energy efficiency, reduced congestion, and a longer network lifespan. The performance of the proposed 6G framework will be validated against existing models to assess its effectiveness.
Sangeetha E, D. J· Journal of universal compute...· 0 citations
This paper presents detailed algorithm for calculating L-LSR coefficient, and shows that L-LSR algorithm not only performs better than OSPF, but also has verySignificant performance improvement over the other LSR family of algorithms.