交换机中ACL配置信息的内容和作用是什么
详解分析，谢谢
各品牌的变频器端子标号都不同。
以台达M型号变频器为例：M0正转端子，M1反转端子，GND公共点。
调速方式在变频器设置，一般采用0-10v信号：+10V是电源，AVI是调速，GND是公共点。
具体需要你把变频器品牌型号发过来，我帮你参考。
请各位英语达人帮我翻译一下软件工程师简历中的 项目经验 不胜感激
我还是把三条一起发给你吧。
项目经验： Project Experience1. XX服装企业分销网络系统1. Distribution Network System for ××Clothing Enterprise 项目介绍：该系统实现了服装企业对服装分销流程的信息化支持，系统的主要功能模块有：分销商库存管理、流向单管理、统计报表管理、分销费管理、付款结帐管理、基础数据管理等。
本系统主要对企业的物流和资金流进行全面的管理和控制。
Project Introduction: This system realizes the information support to the distribution flow of clothing enterprises. The main function modules include: distributor stocking management, flow direction form management, statistics form management, distribution fees management, payment and check-out management, basic data management, etc. This system is mainly used in the comprehensive management and control on the logistics and capital. 总体技术：基于Jsp + Servlet+ JavaBean技术实现：分为展现层、业务逻辑层、DAO层、PO层，在DAO实现上基于OCP原则采用抽象工厂方法设计模式，DAO层直接封装JDBC数据库操作；在统计报表实现上使用Jfreechart组件，同时还使用了FileUpload上传组件及验证码生成组件等。
Overall Technology: Implemented based on Jsp + Servlet+ JavaBean technology, it is divided into presentation layer, business logic layer, DAO layer, PO layer. The implement of DAO adopts the design mode of abstract factory method based on the OCP principle, and the DAO layer directly packages the operation of JDBC database; and the implement of statistics form adopts Jfreechart component, in the same time FileUpload uploading component and verification-code generation component, etc. are also used. 负责工作：分销商库存管理、数据库设计The responsible work: The design of distributor stocking management and database. 心得体会：对企业分销资源管理系统的业务需求有进一步理解，树结构实现方式，JDBC操作数据库，Jfreechart组件的运用、抽象工厂设计模式实现、一些技术细节等。
Experiences: Got further understanding of the service demand for distribution resources management system used in enterprises, and got further understanding of tree architecture implementation mode, JDBC operation database, the application of Jfreechart component, the implement of abstract factory design pattern, and some details. 2. XX军区首长机关办公自动化系统 2. Office Automation System for Head of ×× Military Area Command 项目介绍：为了加快部队信息化建设进程，提高首长机关的日常办公效率，促进司证后装备部门之间的协调工作，**军区结合自身实际，自主研发的一套OA系统。
总体分机构管理、权限管理、公文流转、系统管理、信息交流、信息发布、知识管理、项目管理、资产管理、考勤管理、人事档案、我的工作台等模块。
Project Introduction: In order to accelerate the information construction of the troops, enhance the routine work efficiency of head office, ensure the coordinated work among Command, Political Dept, Logistics Dept, and Equipment Dept, ×× Military Area Command combines self practical situation, and develops an OA system on the basis of itself. The overall system is divided into the following modules: institution management, rights management, documents flow, system management, information exchange, information release, knowledge management, project management, properties management, attendance management, HR archives, my workstation, and so on. 总体技术：基于Struts+ Spring+JBPM+ Hibernate的多层架构：展现层使用Struts来实现MVC模式，通过page-taglib实现分页，采用JSTL与自定义标签，使用Ajax技术使系统具有较好的用户体验；业务逻辑层利用Spring的IOC来维护业务对象之间的关联，利用Spring的AOP进行声明式事务管理，采用贫血Domain Object模型；持久化层使用hibernate来实现，通过DAO模式封装PO对象；将JBPM与Spring整合，实现公文流转模块；结合Freemarker模板技术实现动态表单定义模型；实现扩展的基于RBAC授权与认证模型；实现职能型的组织机构模型。
Overall Technology: A framework with multi layers based on Struts+ Spring+JBPM+ Hibernate. The presentation layer adopts Struts to realize MVC mode, adopts page-taglib to realize paging, adopts JSTL and custom tag, adopts Ajax technology to make system having better user experience; the business logic layer utilizes IOC of Spring to maintain the link between business objects, utilizes AOP of Spring to provide declarative transaction management, adopts anemia-type Domain Object model; the dada persistence layer adopts hibernate to realize, and adopts DAO mode to package PO object; Through the integration of JBPM and Spring to realize the document flow module; through the combination with Freemarker template technology to realize dynamic form definition model; to realize expanded authorize and authentication model based on RBCA; to realize functional organization model.责任描述：参与总体需求分析与架构设计、Domain Object设计、数据库设计、SSH架构搭建及JBPM的整合；同时实现主要模块机构管理、权限管理和公文流转核心模块的设计实现 Responsibility Description: Participated in the analysis of overall demands and the design of framework, the design of Domain Object, the design of database, the building of SSH framework, the integration of JBPM; In the same time realized the management of main module organizations, rights management, and the design and realization of document flow core module. 心得体会：对基于SSH架构的多层应用有深入体会，对工作流引擎JBPM的流程定义、部署和多种类型流程节点使用有进一步理解，基于RBAC模式能进行授权认证模块的实现，在该项目中的许多技术细节如：ACL的设计技巧，DWR实现动态授权，DOM4J实现初始化数据注入等等。
Experience: Got deep understanding of the multi layer application of SSH framework, and got further understanding of the flowing definition, deployment of workflow engine, JBPM, and the application of various kinds of flowing nodes. It is also further understood that based on RBAC mode the authorize and authentication module can be realized. Moreover, many technological details in this project, such as the design skills of ACL, the realization of dynamic authorization with DWR, the realization the injection of initial data with DOM4J, etc. are also understood further. 3. 企业客户关系管理系统 3.Customer Relationship Management System for Enterprises 项目介绍：本项目旨在“以客户为中心，以市场为导向”的企业经营管理模式，通过集中管理客户信息，并在市场部、销售部、服务部等间共享客户数据，从而实现企业市场营销、销售管理、客户服务和支持等经营流程信息化，达到提高客户服务效率和销售人员事务处理的效率，最终实现企业资源的有效利用，提高企业的客户服务质量与核心竞争力。
Project Introduction: This project aims at the enterprise management mode of “ Customer-oriented and Market-oriented”, It shares customer’s information with Marketing Dept, Sales Dept, and Service Dept through the concentrated management of customer’s information, so that realizes the informationization of enterprise’s operation flow such as marketing, sales management, customer service and support, and enhances the service efficiency for customers and the affairs treatment efficiency of sales staffs, finally realizes the effective utilization of enterprise resources and enhance its service quality and core competitive power. 总体技术：采用JSF + Spring + Ibatis + Jfreechart的技术实现：展现层JSF采用Apache的myfaces1.1.1实现包，JSF基于组件、事件和后台bean的交互来开发应用，而不再基于请求相应和标记来解决展现层问题；利用Spring来解耦合，管理依赖，将整个应用进行整合；持久化层采用轻量级的ORM解决方案ibatis；对系统中的多种报表生成采用Jfreechart技术。
Overall Technology: It is realized using JSF + Spring + Ibatis +Jfreechart technology. In presentation layer JSF adopts myfaces 1.1.1 of Apache to realize packet, JSF is developed and applied based on interaction of components, events and background bean instead of basing on request corresponding and marks to solve the problems of the presentation layer; it adopts Spring to decouple, manage dependence, and integrate the overall application; the data persistence layer adopts light duty ORM solution, ibatis; and the generation of various kinds of form in the system adopts Jfreechart technology 负责工作：参与需求分析，数据库分析设计，销售管理模块实现Responsible work: Participated in the demand analysis, the analysis and design of database, and the realization of sales management module. 心得体会：对本项目背景和需求有进一步理解，项目中使用的许多技术细节，如：使用Sitemesh控制页面布局，理解Sitemesh基本原理；利用POI库操纵Excel报表（批量导入和批量导出客户数据）等等。
Experiences: Got further understanding of the background and demand of this project, many details used in this project, such as using Sitemesh to control page layout, understanding the basic principle of Sitemesh; utilizing POI database to handle Excel forms (batch input and batch output the customer’s data), are also deeper understood)
求 service model 软件，物流仿真软件
哪位达人能够提供，感谢之至。
话近网络虚拟化（Networking Virtualization，NVSDN真实热得发烫，先谈我个人的理解和看法。
由有实际玩过相应的产品，所以也只是停留在理论阶段，而且尚在学习中，有些地方难以理解甚至理解错误，因此，特地来和大家交流一下。
早在2009年就出现了SDN（Software Defined Networking）的概念，但最近才开始被众人所关注，主要还是因为Google跳出来表态其内部数据中心所有网络都开始采用OpenFlow进行控制，将OpenFlow从原本仅是学术性的东西瞬间推到了商用领域。
第二个劲爆的消息就是VMWare大手笔12.6个亿$收掉了网络虚拟化公司Nicira。
SDN只是一个理念，归根结底，她是要实现可编程网络，将原本封闭的网络设备控制面（Control Plane）完全拿到“盒子”外边，由集中的控制器来管理，而该控制器是完全开放的，因此你可以定义任何想实现的机制和协议。
比如你不喜欢交换机\\\/路由器自身所内置的TCP协议，希望通过编程的方式对其进行修改，甚至去掉它，完全由另一个控制协议取代也是可以的。
正是因为这种开放性，使得网络的发展空间变为无限可能，换句话说，只有你想不到，没有你做不到。
那SDN为什么会和NV扯上关系呢
其实他们之间并没有因果关系，SDN不是为实现网络虚拟化而设计的，但正式因为SDN架构的先进性，使得网络虚拟化的任务也得以实现。
很多人（包括我自己）在最初接触SDN的时候，甚至认为她就是NV，但实际上SDN的目光要远大得多，用句数学术语来说就是“NV包含于SDN，SDN包含NV”。
再来看看NV，为什么NV会如此火爆，归根结底还是因为云计算的崛起。
服务器\\\/存储虚拟化为云计算提供了基础架构支撑，也已经有成熟的产品和解决方案，但你会发现一个问题，即便如此，虚拟机的迁移依然不够灵活，例如VMWare vMotion可以做到VM在线迁移，EMC VPLEX可以做到双活站点，但虚拟机的网络（地址、策略、安全、VLAN、ACL等等）依然死死地与物理设备耦合在一起，即便虚拟机从一个子网成功地迁移到另一个子网，但你依然需要改变其IP地址，而这一过程，必然会有停机。
另外，很多策略通常也是基于地址的，地址改了，策略有得改，所以依然是手动活，繁杂且易出错。
所以说，要实现Full VM Migration，即不需要更改任何现有配置，把逻辑对象（比如IP地址）与物理网络设备去耦（decouple）才行。
这是一个举例，总而言之，目的就是实现VM Migration Anywhere within the DataCenter non-disruptively，尤其是在云这样的多租户（Multi-tanency）环境里，为每一个租户提供完整的网络视图，实现真正的敏捷商务模型，才能吸引更多人投身于云计算。
SDN不是网络虚拟化的唯一做法，Network overly（mac in mac, ip in ip）的方式也是现在很多公司实际在使用的，比如Microsoft NVGRE、Cisco\\\/VMWare VXLAN、Cisco OTV、Nicira STT等。
事实上overly network似乎已经成为NV实现的标准做法，SDN模型下的NV实现目前更多的是在学术、研究领域。
新技术总是伴随大量的竞争者，都想在此分一杯羹，甚至最后成为标准。
好戏才刚刚上演，相信会越发精彩。
个人觉得这是一个非常有意思的话题，希望和大家交流心得，互相学习.NV的目标就是如何呈现一个完全的网络给云环境中的每一个租户，租户可能会要求使用任何其希望使用的IP地址段，任何拓扑，当然更不希望在迁移至公共云的情况下需要更改其原本的IP地址，因为这意味着停机。
所以，客户希望有一个安全且完全隔离的网络环境，保证不会与其他租户产生冲突。
既然vMotion之类的功能能够让虚拟机在云中自由在线漂移，那网络是否也能随之漂移呢
这里简单介绍下微软的Hyper-v networking virtualization，到不是因为技术有多先进，只不过他的实现细节比较公开，而其它公司的具体做法相对封闭，难以举例。
其实微软的思路很简单，就是将原本虚拟机的二层Frame通过NVGRE再次封装到 IP packet中进行传输，使得交换机能够通过识别NVGRE的Key字段来判断数据包的最终目的地。
这其实就是一个Network Overlay的做法，它将虚拟网络与物理网络进行了分离。
试想，公司A和公司B都迁移到公有云且就那么巧，他们的一些虚拟机连接到了同一个物理交换机上，现在的问题是，他们各自的虚拟机原本使用的私有IP段是一样的，如果没有VLAN就会导致IP冲突。
但现在看来，这已经不是问题，因为虚拟机之间的通信都要通过NVGRE的封装，而新的IP包在物理网络上传输时是走物理地址空间的，而物理地址空间是由云服务提供者所独占的，因此不存在IP冲突的情况。
总结一下就是，这里的网络虚拟化可以认为是IP地址虚拟化，将虚拟网络的IP与物理网络完全分离，这样做就可以避免IP冲突，跨子网在线迁移虚拟机的问题，微软的要求是：虚拟机可以在数据中心中任意移动，而客户不会有任何感觉，这种移动能力带来了极大的灵活性。
Software-defined networking (SDN) is an approach to computer networking which evolved from work done at UC Berkeley and Stanford University around 2008.[1] SDN allows network administrators to manage network services throughabstraction of lower level functionality. This is done by decoupling the system that makes decisions about where traffic is sent (the control plane) from the underlying systems that forwards traffic to the selected destination (the data plane). The inventors and vendors of these systems claim that this simplifies networking.[2]SDN requires some method for the control plane to communicate with the data plane. One such mechanism, OpenFlow, is often misunderstood to be equivalent to SDN, but other mechanisms could also fit into the concept. The Open Networking Foundation was founded to promote SDN and OpenFlow, marketing the use of the term cloud computing before it became popular.This section does not cite any references or sources. Please help improve this section by adding citations to reliable sources. Unsourced material may be challenged andremoved. (February 2013) One application of SDN is the infrastructure as a service (IaaS).This extension means that SDN virtual networking combined with virtual compute (VMs) and virtual storage can emulate elastic resource allocation as if each such enterprise application was written like a Google or Facebook application. In the vast majority of these applications resource allocation is statically mapped in inter process communication (IPC). However if such mapping can be expanded or reduced to large (many cores) or small VMs the behavior would be much like one of the purpose built large Internet applications.Other uses in the consolidated data-center include consolidation of spare capacity stranded in static partition of racks to pods. Pooling these spare capacities results in significant reduction of computing resources. Pooling the active resources increases average utilization.The use of SDN distributed and global edge control also includes the ability to balance load on lots of links leading from the racks to the switching spine of the data-center. Without SDN this task is done using traditional link-state updates that update all locations upon change in any location. Distributed global SDN measurements may extend the cap on the scale of physical clusters. Other data-center uses being listed are distributed application load balancing, distributed fire-walls, and similar adaptations to original networking functions that arise from dynamic, any location or rack allocation of compute resources.Other uses of SDN in enterprise or carrier managed network services (MNS) address the traditional and geo-distributed campus network. These environments were always challenged by the complexities of moves-adds-changes, mergers & acquisitions, and movement of users. Based on SDN principles, it expected that these identity and policy management challenges could be addressed using global definitions and decoupled from the physical interfaces of the network infrastructure. In place infrastructure on the other hand of potentially thousands of switches and routers can remain intact.It has been noted that this overlay approach raises a high likelihood of inefficiency and low performance by ignoring the characteristics of the underlying infrastructure. Hence, carriers have identified the gaps in overlays and asked for them to be filled by SDN solutions that take traffic, topology, and equipment into account.[7]SDN deployment models[edit]This section does not cite any references or sources. Please help improve this section by adding citations to reliable sources. Unsourced material may be challenged andremoved. (February 2013) Symmetric vs asymmetricIn an asymmetric model, SDN global information is centralized as much as possible, and edge driving is distributed as much as possible. The considerations behind such an approach are clear, centralization makes global consolidation a lot easier, and distribution lowers SDN traffic aggregation-encapsulation pressures. This model however raises questions regarding the exact relationships between these very different types of SDN elements as far as coherency, scale-out simplicity, and multi-location high-availability, questions which do not come up when using traditional AS based networking models. In a Symmetrically distributed SDN model an effort is applied to increase global information distribution ability, and SDN aggregation performance ability so that the SDN elements are basically one type of component. A group of such elements can form an SDN overlay as long as there is network reachability among any subset.Floodless vs flood-basedIn a flood-based model, a significant amount of the global information sharing is achieved using well known broadcast and multicast mechanisms. This can help make SDN models more Symmetric and it leverages existing transparent bridging principles encapsulated dynamically in order to achieve global awareness and identity learning. One of the downsides of this approach is that as more locations are added, the load per location increases, which degrades scalability. In a FloodLess model, all forwarding is based on global exact match, which is typically achieved using Distributed Hashing and Distributed Caching of SDN lookup tables.Host-based vs Network-centricIn a host-based model an assumption is made regarding use of SDN in data-centers with lots of virtual machines moving to enable elasticity. Under this assumption the SDN encapsulation processing is already done at the host HyperVisor on behalf of the local virtual machines. This design reduces SDN edge traffic pressures and uses free processing based on each host spare core capacity. In a NetworkCentric design a clearer demarcation is made between network edge and end points. Such an SDN edge is associated with the access of Top of Rack device and outside the host endpoints. This is a more traditional approach to networking that does not count on end-points to perform any routing function.Some of the lines between these design models may not be completely sharp. For example in data-centers using compute fabrics Big hosts with lots of CPU cards perform also some of the TopOfRack access functions and can concentrate SDN Edge functions on behalf of all the CPU cards in a chassis. This would be both HostBased and NetworkCentric design. There may also be dependency between these design variants, for example a HostBased implementation will typically mandate an Asymmetric centralized Lookup or Orchestration service to help organize a large distribution. Symmetric and FloodLess implementation model would typically mandate in-network SDN aggregation to enable lookup distribution to a reasonable amount of Edge points. Such concentration relies on local OpenFlow interfaces in order to sustain traffic encapsulation pressures.[5] [6]
CCNA自学的问题
教材可以用《CCNA学习指南-第六版》80一本，一般都用中文版。
考试时英文版，教材看中文版的容易看些，英文版的不容易看得懂。
如果你英文好，那你就看英文的。
考试中心就可以报名。
考试费是125美金，每个考场收费不一样，你自己找个便宜的考场。
CCNA最好别自己学，一个是学的慢，另外一个是碰不到设备，路由交换设备很重要，没碰过设备到真正工作的时候还是着急。
模拟器我用的是vmware，也就是在ITAA学习组下载的虚拟机包含dynamips实验。
