The concept of cloud storage (cloud storage), once proposed, has been supported and concerned by many vendors. Amazon's elastic Compute Cloud (EC2: Resilient computing Cloud) cloud storage product, launched two years ago, is designed to provide users with more powerful storage and computing capabilities in the form of Internet services. Content distribution Network service provider CDNetworks and the industry's renowned cloud storage platform service provider Nirvanix released a new partnership and announced a strategic partnership to provide the industry's only current cloud storage and content delivery service integration platform. Six months ago, Microsoft had launched the Windows Live SkyDrive Beta test version of the network mobile hard drive service. In the near future, EMC has announced the inclusion of a trusted infrastructure project, dedicated to global research collaboration on trust and reliability assurance in the cloud computing environment, and IBM has also taken cloud computing as part of its 300 million dollar expansion plan for global backup centers.
Cloud storage becomes more and more hot, we talk about "cloud", and each has its own argument, each has its own views, so what is the cloud storage?
1 What is cloud storage
Cloud storage is a new concept that extends and develops in the concept of cloud computing (cloud computing). Cloud computing is the development of distributed processing (distributed Computing), parallel processing (Parallel Computing) and Grid computing (grids Computing), which automatically splits large computational handlers into countless smaller subroutines through the network, A large system of multiple servers is calculated and analyzed to pass the processing results back to the user. With cloud computing technology, Web service providers can handle tens of millions of billions of dollars of information in a matter of seconds to achieve the same powerful network services as supercomputers.
Cloud storage concept is similar to cloud computing, it refers to the network through the cluster application, grid technology, or Distributed file system functions, a large number of different types of storage devices in networks through the application software together to work together to provide data storage and business access functions of a system.
If this explanation is still difficult to understand, we can use the structure of WAN and internet to explain cloud storage.
Cloud-like network structure
I believe you have a good understanding of LAN, WAN and Internet. In the common LAN system, we in order to better use the local area network, generally speaking, users need to know very clearly the network of each hardware and software model and configuration, such as what type of switch, how many ports, the use of what routers and firewalls, respectively, how to set. How many servers are in the system, and what operating systems and software are installed separately. What type of connection cables are used between the devices, and what XML:LANG=IP addresses and subnet masks are assigned.
But when we use the wide area network and the Internet, we just need to know what access network and username, password can connect to the WAN and the Internet, do not need to know how many switches, routers, firewalls and servers in the WAN and Internet, do not need to know the data is through what route to our computer , you don't need to know what software is installed on your network, and you don't need to know what connection cables and ports are used between the devices in your network.
The wide area network and the Internet are completely transparent to specific users, and we often use a cloud-like graph to represent the wide area network and the Internet, as shown below:
Although the cloud contains many switches, routers, firewalls, and servers, these are not needed for specific WANs and Internet users. This cloud-like graphics represents the wide area network and the Internet to bring you the interconnection of Internet services, no matter where we can through a network access cable and a user, password, you can access the WAN and the Internet, enjoy the network to bring our services.
Reference cloud network structure, create a new cloud-like structure of the storage system, the storage system consists of a number of storage devices, through the cluster function, distributed file system or similar grid computing functions together to work together, and through a certain application software or application interface, Provide a certain type of storage service and access service to the user.
When we use a separate storage device, we have to be very clear about what type of storage device, what interfaces and transport protocols you have, how many disks there are in the storage system, what type, what size, and what kind of connection cable to use between the storage device and the server. In order to ensure data security and business continuity, we also need to establish corresponding data backup system and disaster tolerance system. In addition, regular state monitoring, maintenance, software and hardware updates and upgrades are necessary for storage devices.
If you are using cloud storage, everything mentioned above will not be needed for users. All devices in a cloud-like storage system are completely transparent to the user, and any authorized user anywhere can access the cloud storage via a single access cable to the cloud storage.
Cloud storage is not storage, but service
Like a cloud wide area network and the Internet, cloud storage does not refer to a specific device, but to a collection of many storage devices and servers. Using cloud storage, the consumer does not use a single storage device, but rather a data access service that comes with the entire cloud storage system. So strictly speaking, cloud storage is not storage, but a service.
The core of cloud storage is the combination of application software and storage device to realize the transformation of storage device to storage service through application software.
2 cloud storage structure Model
Compared with traditional storage devices, cloud storage is not only a hardware, but a complex system consisting of a network device, a storage device, a server, an application software, a public access interface, an access network, and a client program. Each part takes the storage device as the core, through the application software to provide the data storage and the business access service externally. The structure model of the cloud storage system is as follows:
The structure model of cloud storage system consists of 4 layers.
Storage Layer
The storage layer is the most basic part of cloud storage. Storage devices can be FC Fibre Channel storage devices, IP storage devices such as NAS and iSCSI, or DAS storage devices such as SCSI or SAS. Storage devices in cloud storage are often large and geographically diverse, connected to each other over a wide area network, the Internet, or FC Fibre Channel networks.
Above the storage device is a unified storage device management system, which can realize the logical virtualization management of storage devices, Multilink redundancy management, and the condition monitoring and fault maintenance of hardware devices.
Second, the basic management layer:
The base management layer is the core part of cloud storage and the most difficult part of cloud storage. Through clustering, distributed file system and Grid computing, the basic management realizes the collaborative work among multiple storage devices in cloud storage, so that multiple storage devices can provide the same service externally, and provide greater and stronger data access performance.
CDN Content distribution System, data encryption technology to ensure that the data in the cloud storage will not be accessed by unauthorized users, at the same time, through a variety of data backup and disaster-tolerant technology and measures to ensure that the data in the cloud storage will not be lost, to ensure the security and stability of the cloud storage.
Third, the application interface layer:
Application interface layer is the most flexible and changeable part of cloud storage. Different cloud storage operating units can develop different application service interfaces and provide different application services according to the actual business type. such as video surveillance application platform, IPTV and video-on-demand application platform, network hard disk reference platform, remote data backup application platform.
Iv. Access Layer:
Any authorized user can login to the cloud storage system through the standard common application interface and enjoy the cloud storage service. Cloud storage operates in different units, and cloud storage provides different types of access and means of access.
3 Cloud Storage Technology Prerequisites
From the above cloud storage structure model, we know that cloud storage System is a collection of multi device, multi application and multi service collaborative work, and its realization should be based on the development of many technologies.
The development of broadband network
The real cloud storage system will be a multiple-region distribution, across the country, and even around the world's vast public systems, users need to connect to the cloud via ADSL, DDN, and other broadband access devices, rather than via FC, SCSI, or Ethernet cables directly connected to a stand-alone, private storage device. Only if the broadband network is fully developed, users will be able to obtain large enough data transmission bandwidth, to achieve a large number of capacity to transmit information, really enjoy the cloud storage services, otherwise it can only be empty talk.
Ii. WEB2.0 Technology
The core of Web2.0 technology is sharing. Only through web2.0 technology, the users of cloud storage can realize the centralized storage and data sharing of data, documents, pictures and audio and video through PCs, mobile phones, mobile multimedia and other devices. The development of Web2.0 technology enables users to be more flexible and versatile in their applications and services.
III. Application Storage Development
Cloud storage is not just storage, it is more applications. Application storage is a storage device that integrates the function of application software, which not only has the function of data storage, but also has the function of application software, which can be regarded as a collection of servers and storage devices. The development of application storage technology can reduce the number of servers in cloud storage, reduce the cost of system construction, reduce the single point fault and performance bottleneck in the system, reduce the data transmission link, provide system performance and efficiency, and ensure the efficient and stable operation of the whole system.
Iv. cluster technology, grid technology and Distributed File system
The cloud storage System is a collection of multiple storage devices, multiple applications, and multiple services, and any single point of storage system is not cloud storage.
Since it is composed of multiple storage devices, among different storage devices, it is necessary to realize the cooperative work among multiple storage devices through cluster technology, distributed File system and grid computing, so that multiple storage devices can provide the same service and provide greater and stronger data access performance. Without the existence of these technologies, cloud storage could not be truly implemented, and the so-called cloud storage could only be a single system, not a cloud-like structure.
CDN Content Distribution, Peer-to-peer technology, data compression technology, duplicate data deletion technology, data encryption technology
CDN Content distribution System, data encryption technology to ensure that the data in the cloud storage will not be accessed by unauthorized users, at the same time, through a variety of data backup and disaster-tolerant technology to ensure that the data in the cloud storage is not lost, to ensure the security and stability of the cloud storage. If the data security in the cloud storage is not guaranteed, and no one dares to use cloud storage, otherwise, the saved data is not quickly lost, is the whole country know.
Vi. Storage Virtualization Technology, storage networked management technology
The number of storage devices in cloud storage is large and distributed across many different geographies, how to implement logical volume management, storage virtualization management, and Multilink redundancy management between multiple devices of different vendors, different models, and even different types, such as FC storage and IP storage, will be a huge problem, Storage devices can be the performance bottleneck of the entire cloud storage system, the structure can not form a whole, but also bring late capacity and performance expansion difficult issues.
Storage device Operation management issues are another problem with a large number of storage devices in the cloud storage and a wide range of geographical distribution. Although these problems for the users of cloud storage do not need to care, but for the operation of cloud storage units, but must be through practical and effective means to solve the problem of centralized management, state monitoring is difficult, trouble maintenance, human cost high. Therefore, cloud storage must have an efficient and similar centralized management platform like network management software to achieve centralized management and state monitoring of storage devices, servers, and network devices in a cloud storage system.