Lesson 2 Summary: Cloud Storage and Content Delivery Networks第 2 课总结：云存储和内容分发网络

In this lesson, you have learned:
在这一课中，你学到了：

• Cloud storage is available in four main types–Direct Attached, File, Block, and Object Storage. These storage types differ in how they can be accessed, the capacity they offer, how much they cost, the types of data they are best suited to store, and their read-write speed.
  云存储主要有四种类型——直接附加存储、文件存储、块存储和对象存储。这些存储类型在访问方式、提供的容量、成本、最适合存储的数据类型以及读写速度方面有所不同。
• Direct Attached (or Local) Storage is storage that is presented directly to a cloud-based server and is effectively either within the host server chassis or within the same rack.
  直接连接（或本地）存储是指直接呈现给基于云的服务器的存储，实际上位于主机服务器机箱内或同一机架内。
• File Storage is typically presented to compute nodes as a Network File System (NFS), which means that the storage is connected to compute nodes over a standard ethernet network.
  文件存储通常以网络文件系统（NFS）的形式呈现给计算节点，这意味着存储通过标准以太网连接到计算节点。
• Block Storage is presented to compute nodes using high-speed fiber connections, typically provisioned in volumes, which are mounted onto a compute node. 
  块存储通过高速光纤连接提供给计算节点，通常以卷的形式配置，并挂载到计算节点上。
• Object Storage is accessed via an API and doesn’t need an underlying compute node.
  对象存储通过 API 访问，不需要底层计算节点。
• Object Storage offers infinite capacity as you can keep adding files to it and just pay for what you use. Compared to the other storage types, object storage is slowest in terms of read and write speeds.
  对象存储提供无限容量，您可以不断向其中添加文件，只需为使用的部分付费。与其他存储类型相比，对象存储在读写速度方面最慢。
• A Content Delivery Network (CDN) is a distributed server network that accelerates internet content delivery by delivering temporarily stored or cached copies of website or media content to users based on their geographic location.
  内容分发网络（CDN）是一种分布式服务器网络，通过根据用户的地理位置将临时存储或缓存的网站或媒体内容的副本发送给用户，从而加速互联网内容的分发。