虚网络数据管理协议(2)

Data Replication

　　This agnostic view of whether a data service is a producer or consumer lends itself to data replication. One storage system can provide a data stream that is consumed by an identical storage system, and the data is copied from one system to another.
In an NDMP session, there is always one TCP/IP connection between each service and the software that centrally manages the network's backup and recovery operations, which is the data management application. NDMP is geared toward facilitating centralized control of backup and recovery operations. The client initiates contact with services via a well-known TCP/IP port and then follows up with a standard command-and-response dialogue, which is effectively a state machine, with the state maintained on the client. The data services are moved through states with names such as "Idle," "Listen," "Active" and "Halted."
Version 5 is concerned with Internet issues, such as security authorization and networks that exist across the Web (which is one of the reasons the NDMP working group has migrated from the Storage Networking Industry Association to the Internet Engineering Task Force). (The End)

虚网络数据管理协议(2)

数据复制

　　数据服务是生产者还是消费者的不可知性有助于数据复制。一个存储系统可以提供数据流，供同一存储系统消费，这样数据就从一个系统拷贝到另一系统。
在NDMP会话中，每个服务和集中管理网络备份和恢复操作的软件之间总是有一个TCP/IP连接，这就是数据管理应用。NDMP是用来方便集中控制备份和恢复操作的。客户通过著名的TCP/IP口启动与服务的接触，随后就是标准的命令和响应对话，实际上这就是状态机，在客户端维持此状态。数据服务在各种状态（如空闲、监听、便用和暂停等）之间进行移动的。
第5版与互联网的问题有关，如安全认证和存在于Web上的网络等（这就是NDMP工作小组从存储网络工业协会转到互联网工程任务组的理由之一）。