PON二级分光在全业务组网中的应用探析

本文通过对比分析二级分光在光链路衰减、资源占用、投资、扩容、装维等方面的优劣,总结二级分光在全业务组网中的优势,以及适用的场景,并给出多层住宅、高层住宅和聚类市场等典型场景中的组网规划。     

集团客户MPLS-VPN业务组网及性能测试研究

本文从MPLS原理入手,介绍MPLS VPN的二层、三层组网方式。根据运营商现网应用的实践,重点介绍三层MPLS VPN跨省、跨境业务的典型组网,总结MPLS VPN业务组网、业务承载、传输接入、QoS保障、扩展性及专业网管监控等方面的优点。同时,针对客户感知需求,提出业务网络性能测试的指标及方法。     

面向密集多波束组网的卫星通信系统资源调度算法

研究了高动态、资源受限条件下的卫星通信系统资源调度问题.以时间窗口、卫星功耗、信道数量、用户优先级以及任务突发性为约束,建立了卫星资源调度模型.考虑到传统的蚁群优化算法存在初期搜索速度过慢、局部搜索能力较弱以及易陷入局部最优等缺点,提出了以初始解集构造、额外信息素沉积为核心的改进蚁群优化算法,来求解资源调度问题.仿真实...     

Molecular Networking,Network Pharmacology,and Molecular Docking Approaches Employed to Investigate the Changes in Ephedrae Herba before and after Honey-Processing

Raw Ephedrae herba (REH) and honey-processed Ephedrae herba (HEH) were the different decoction pieces of Ephedrae herba (EH). Honey-processing that changes REH into HEH has been shown to relieve cough and asthma to a synergistic extent. However, the chemical markers and the synergistic mechanism of HEH need to be further studied. In this study, the ultra-high performance liquid chromatography coupled with hybrid quadrupole time of flight mass spectrometry (UPLC-Q-TOF-MS) and molecular networking (MN) were used to investigate the chemical composition of REH and HEH, which led to the identification of 92 compounds. A total of 38 differential chemical markers for REH and HEH were identified using principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA). Network pharmacology suggests that the synergistic effect of HEH in relieving cough and asthma may be due to 31 differential chemical markers acting through 111 biological targets. Among them, four compounds and two targets probably played an important role based on the results of molecular docking. This study enriched our knowledge about the chemical composition of REH and HEH, as well as the synergistic mechanism of HEH.     

车联网场景下基于内容中心网络的优化缓存策略

车联网中,如何有效选择缓存位置和缓存内容对于提高整体网络性能至关重要。针对上述问题,引入了内容中心网络技术,提出了一种新的优化缓存策略——缓存位置和缓存内容的选择取决于车辆节点值和内容流行度(Vehicle Node Value and Content Popularity,VNVCP)。首先,定义了连通性、中间中心性和特征向量中心性3个车辆节点属性用来评估车辆节点的值,具有不同值的车辆节点缓存具有不同流行度的内容,内容的重要性由其受欢迎程度决定。其次,该策略利用不同类型内容受欢迎程度的差异确保缓存内容分布均匀,同时评估来自多个属性的车辆节点的值以提高车辆节点利用率。仿真结果表明,VNVCP在缓存命中率、平均跳数和传输延迟方面明显优于传统的LCE(Leave Copy Every where)、Prob(0.5)和MPC(Most Popular Content)。     

SD-FANET下基于节点合作的低开销且可靠有效路由解决方案

针对分布式无人机网络初始建网时间过长、周期性组网开销过大、链路稳定性与可靠性低的问题,提出了软件定义飞行自组网下基于节点合作的低开销且可靠有效路由解决方案（Low-overhead,Reliable and Efficient Routing Solution Based on Node Cooperation,NC-SDN）。首先,通过普通节点局部感知和软件定义网络（Software Defined Network,SDN）控制器全局感知配合,缩短了初始建网时间并减少了周期性组网开销;其次,通过普通节点主动感知链路状态与周期性传递告警信息,减少了未过期无效路由带来的不可靠传输风险;最后,通过SDN控制器的预测与切换,降低了用户业务传输中断的风险。仿真表明,NC-SDN在初始建网时间、周期性组网开销和丢包率等方面性能优于现有的SDN、优化链路状态路由和无线自组网按需平面距离向量路由。     

P4toNFV: Offloading from P4 switches to NFV in programmable data planes

P4 combines the benefits of hardware-based networking with the adaptability of software-based network operations. However, when faced with intricate network functions, P4 switches reveal constraints in memory and processing primitives. To address these, we advocate offloading traffic demanding intricate processing from the programmable data plane to network function virtualization (NFV). By leveraging this approach, P4 switches handle the core data plane, ensuring maximum performance, whereas virtualized network functions (VNF) cater to the intricate processing. Central to our research is the optimization of this offloading process, specifically considering delay constraints. We developed an analytical model that examines a P4 switch overseen by an SDN controller, integrating an offloading capability to NFV. The principal objective was to determine an offloading rate that minimizes packet processing delay. To this end, we employed a Bounded method, an advancement from Brent's method, to determine this optimal rate. The findings indicate that offloading approximately 66% of packets to the VNF achieves the lowest total delay, registering at 0.1505 $$s. This strategy of optimal offloading can notably reduce the system's average delay as the demand for network functions increases. The optimization technique we adopted exhibited rapid convergence in our experiments, reflecting the method's efficacy. Furthermore, a rigorous parametric sensitivity analysis spanning no offloading, full offloading, and optimal offloading strategies underscores that optimal offloading to NFV consistently augments system performance, particularly in terms of delay reduction. Conclusively, our study furnishes valuable insights into offloading strategies, augmenting the narrative on resource allocation in both PNFs and VNFs.     

面向6G的星地融合无线传输技术

随着5G移动通信网络走向商业化,围绕新一代移动通信系统(6G)的发展愿景、能力需求与关键技术开展研究正在成为新的热点。首先,该文概括了未来6G可能涉及的星地深度融合、新谱段通信、分布式协作MIMO和智能通信等关键技术方向,重点探讨了基于星地深度融合的天地一体化网络(SGIN);然后,针对可能存在的两种典型网络拓扑架构,分析了星间高速链路、星地馈电链路和星地用户链路的特点和技术要求,综述了3种不同类型传输链路的高速通信进展情况。最后,对未来6G天地互联网络亟需突破的光学相控阵多用户接入、高效能星地激光通信和光电一体化组网等关键技术进行分析与展望,以期为后续相关研究指明方向。     

嵌入式无线网络化测控仪器关键技术研究与实现

在现实生活中,测控仪器的使用是非常广泛的,最为常见的就是将仪器用在信息处理和大数据计算上,将嵌入式的网络操作系统应用在网络测控之中,利用嵌入式网络进行网络仪器的整合和硬软件的更新成了当下亟待解决的问题,是实现信息储存和数据记录的现实条件.文章就嵌入式无线网络测控仪器关键技术展开研究,对其技术的实现形式展开探讨.     

距离约束分簇策略下无人机群空地组网性能分析

在无人机(UAV)辅助的能量受限低功耗物联网(IoT)节点数据传输场景中,针对传统的Matérn聚类过程 (MCP)建模造成的无人机覆盖冗余问题,该文提出一种Matérn集群下的距离约束分簇策略(MCDC)。该策略采用带有距离约束的Matérn聚类过程对无人机和地面IoT节点位置进行了建模,实现冗余覆盖的大幅度下降。在此分布策略下,IoT节点首先通过从无人机发送的射频信号中收集能量,然后利用收集的能量向无人机进行上行数据传输,解决IoT节点能量受限问题。此外,分析了IoT节点传输机会以及无人机群空地网络的上行传输中断性能和吞吐量,并衡量了上下行阶段的时间分配比,无人机的发射功率,以及IoT节点密度等参数对网络性能的影响。最后通过仿真对理论结果进行了验证。