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1.
面向10G城域以太网带宽管理的RPR技术   总被引:3,自引:0,他引:3  
弹性分组环(RPR:resilient packet ring)是当前比较热门的组网技术,它为10G城域以太网提供了一个很好的组网方案。从RPR在10G城域以太网带宽管理方面的优势出发,介绍了其技术特点、标准化及产业化现状,讨论了城域以太网的RPR提案中有利于带宽管理的各种关键技术。  相似文献   

2.
随着现今网络应用的快速发展,用户对带宽的需求日益增大,骨干网和接入网的技术革新又使旧城域网成为网络发展的瓶颈,因此建设新一代城域网已成为各个设备制造商抢占市场的先机, 是运营商拓展业务的重中之重。在介绍了城域网进行改革性建设的必要性、紧迫性以及弹性分组环(RPR)组网技术后, 阐述了10 G以太网作为新一代的全光城域网络传送技术的优势和RPR在10 G城域网以太网组网建设中的优势,探索了RPR的带宽管理技术,并提出了RPR环路带宽共享接入策略和公平接入的构想。  相似文献   

3.
随着现今网络应用的快速发展,用户对带宽的需求日益增大,骨干网和接入网的技术革新又使旧城域网成为网络发展的瓶颈,因此建设新一代城域网已成为各个设备制造商抢占市场的先机,是运营商拓展业务的重中之重。在介绍了城域网进行改革性建设的必要性、紧迫性以及弹性分组环(RPR)组网技术后,阐述了10G以太网作为新一代的全光城域网络传送技术的优势和RPR在10G城域网以太网组网建设中的优势.探索了RPR的带宽管理技术,并提出了RPR环路带宽共享接入策略和公平接入的构想。  相似文献   

4.
基于高速以太网技术的应用探讨   总被引:3,自引:0,他引:3  
高速以太网技术以其速度快、带宽高且兼容性好,比传统标准以太网更具有强大的功能,是目前计算机高速网络的一个新的领域.本文针对高速以太网技术的重要方面,着重讨论了千兆以太网和万兆以太网相互存在的技术特点,及10 GbE与弹性分组数据环(RPR)结合产生的10 G RPR技术,为高速以太网的组网提供了依据.  相似文献   

5.
为适应目前多业务传送的需要,升级以SDH为基础的城域传输网,采用对比优缺点的方法,分析了城域传送网的组网现状,以及光纤直连组网,多业务传送平台技术(MSTP)、城域波分DWDM以及弹性分组环RPR的优点和局限性,阐明了采用以MSTP设备为主,城域DWDM设备为辅.逐步发展RPR设备的组网方案,实现了网络的平滑升级,有效地保护运营商的当前投入。  相似文献   

6.
弹性分组环(RPR)技术结合以太网技术和SDH技术所带来的组合优势,适合于城域网的组网。文章介绍了RPR的网络体系结构、MAC层机制,分析了RPR的技术特点,用实例说明了RPR技术在校园城域网中的优势。  相似文献   

7.
PTN组网是城域传输网实现3G及全业务统一承载的先进组网模型,目前已成为各大移动运营商建设下一代中小型城域传输网的重要解决方案。提出了面向3G和全业务运营的绍兴移动PTN+OTN组网思路和实现方案。  相似文献   

8.
RPR是一种新的MAC层协议和城域网技术,具有空间复用、带宽动态分配、支持业务级别等主要特点,实现采用的是三层结构.讨论了传输网管系统中实现RPR业务分类涉及到的3条Qx接口命令的处理:设置数据板以太网业务属性、设置数据板静态目的站点地址、设置RPR端口环选择.  相似文献   

9.
弹性分组环技术(RPR)   总被引:1,自引:0,他引:1  
弹性分组环(RPR)技术是一种基于以太网技术和标记交换技术相结合的,多业务共存的业务特性的新一代城域网解决方案。主要介绍了弹性分组环(RPR)的MAC协议帧结构,探讨了RPR的基本原理、关键技术和光以太网RPR,并对RPR技术在未来通信网中的发展趋势进行了分析。  相似文献   

10.
两级10G EPON系统物理层方案研究   总被引:1,自引:0,他引:1  
文中主要探讨了一种基于10G EPON的TDM/WDM混合组网方案:在原OLT和ONU之间插入Sub-OLT,在OLT和Sub-OLT之间采用WDM-PON技术,以10G对称速率组网;考虑到节约成本和实现推迟ONU升级的目的,在Sub-OLT和ONU之间则仍采用标准的1G EPON(TDM/TDMA技术)组网.OptiSystem的建模仿真结果表明,该方案既能保持与IEEE802.3/802.3av最大的兼容性,又能够在满足带宽增长的前提下取得成本-效益的最大化.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

19.
20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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