物理层由实际的磁盘组成。
下面我们回到物理层来仔细看看访问器。
Next we switch back to the physical level and take a closer look at accessors.
然而在逻辑层，代码并不知道物理层类型。
However, at the logical level, code is not aware of physical level types.
当我使用层，我引用一个物理层。
通信的物理层和逻辑层可能是一样的。
Both physical and logical layers of communication can be identified.
从概念上讲，逻辑卷层位于应用程序层和物理层之间。
Conceptually, the logical volume layer sits between the application and physical layers.
去尊重你在物理层中于地球上舞蹈的身体。
Honor the body that allows the dance upon Earth in the physical.
还有自己模拟的物理层。
正是在物理层中，它们能最好地服务于提升。
要达到这一目的，需要尽量保持数据库/物理层的简洁。
To achieve this, keep the database/physical layer as clean as possible.
但是，架构师需要了解物理层以避免网络瓶颈和安全暴露。
Architects, however, need to understand the physical layer in order to avoid network bottlenecks and security exposures.
层1和层2分别是物理层和数据链接层，通过以太网实现。
Layers 1 and 2 are the physical and data link layers, respectively, fulfilled by the Ethernet network.
物理层将逻辑层中的组件分配到其部署的物理平台。
Physical tiers allocate the components in the logical tiers to the physical platform to which they are deployed.
与逻辑层系统的灵活性相比，物理层的面向对象的系统显得有些脆弱。
When compared to the flexibility of a logical system, physical level object-oriented systems appear brittle.
称为物理层协议的两个底层处理网络电缆上的实际信号传输。
The two bottom layers, called the physical layer protocols, take care of the actual signal transfer over the network cable.
采用物理层技术设计的系统通常依赖于驻留在架构不同层次上的可变对象。
Systems designed with physical level technologies usually rely on mutable objects residing at various levels of an architecture.
这使得管理员可以在虚拟层，而不用在机器物理层，部署和迁移应用服务器。
This lets administrators deploy and move application servers at a virtualization layer level instead of at the physical machine level.
分布式企业Web应用程序很可能会将逻辑层分布到一系列物理层。
A distributed enterprise Web application would most likely spread the logical tiers across a range of physical tiers.
这是否意味着我们对系统工程学的方法——其要求逻辑层和物理层分离——有缺陷呢？
Does this mean that our approach to systems engineering — which calls for the separation of logical and physical perspectives — is flawed?
通过在物理层之上的逻辑层中定义路由，可以在相同网络结构上实现许多重叠的拓扑。
With routing defined in a logical layer above the physical network, it is possible to have many overlapping topologies implemented on the same network fabric.
这是为什么根植让身体觉得安全，并免于在物理层上遭受任何事故的原因。
This is why grounding allows the body to feel safe and be safe from accidents of any kind upon the physical plane.
逻辑层可以跨物理层，并且可以将一个或多个、甚至所有的层分配到一个物理层。
Logical tiers may span physical tiers, and one or more or all the tiers may be allocated to one physical tier.
由于RPR是第二层基于MAC的技术，所以它能在多个物理层上工作，包括SONET。
Because RPR is a layer 2 MAC-based technology, it can operate over multiple physical layers, including SONET.
这个安排显示了一个瘦客户机部署，其中的全部表示和一些应用程序逻辑都映射到了客户机物理层。
This arrangement shows a thick client deployment in which all the presentation and some of the application logic are mapped to the client physical tier.
我们已经知道了一个逻辑层的URI地址是如何被解析为物理层端点以及开始处理时是如何绑定的。
We have seen how a logical level URI address is resolved to a physical level endpoint and bound to it for the time it takes to process.
但我们不需要把所有VM的联网都强加到这个平台的物理层上，本地通信可自行被虚拟化。
But rather than force all of the VM's networking to the physical layer of the platform, local communication could instead be virtualized itself.
云计算是由多种分层的要素组成，从最基本的物理层存储和服务器基础架构开始，以及应用层和网络层。
Cloud computing is made up of a variety of layered elements, starting at the most basic physical layer of storage and server infrastructure and working up through the application and network layers.
链路层是指提供对物理层访问的设备驱动程序，这可以是各种介质，例如串口链路或以太网设备。
The link layer refers to the device drivers providing access to the physical layer, which could be numerous mediums, such as serial links or Ethernet devices.
了解它位于应用程序层和物理层之间，应该可以帮助您理解它为什么很可能是所有层中最重要的一层。
Understanding that it sits between the application layer and the physical layer should help you understand why it is arguably the most important of all the layers.
了解它位于应用程序层和物理层之间，应该可以帮助您理解它为什么很可能是所有层中最重要的一层。
Understanding that it sits between the application layer and the physical layer should help you understand why it is arguably the most important of all the layers.
应用推荐