In-depth analysis of cloud storage

The concept of cloud storage has received support and attention from many vendors. Amazon launched the Elastic Compute Cloud (EC2: Elastic Computing cloud) cloud storage product two years ago. It aims to provide users with enhanced storage and computing functions in the form of Internet services. Cdnetworks, a content delivery network service provider, and nirvanix, an industry-renowned cloud storage platform service provider, have launched a new partnership and announced a strategic partnership, to provide the industry's only cloud storage and content delivery service integration platform. Half a year ago, Microsoft launched the Windows Live SkyDrive beta version that provides the network mobile hard drive service. Recently, EMC announced that it has joined the trusted infrastructure project in daoli and is committed to global research collaboration on trust and reliability assurance in the cloud computing environment, IBM also uses cloud computing standards as part of a $0.3 billion scale-out solution for global backup centers.

Cloud storage is becoming increasingly popular. Everyone is talking about "cloud" and each has its own opinions and opinions. What is cloud storage?

1. What is cloud storage?

Cloud storage is a new concept that extends and develops in the cloud computing concept. Cloud computing is the development of distributed processing (Distributed Computing), parallel processing (Parallel Computing), and grid computing, it is to automatically split a large computing processing program into countless smaller subprograms through the network, and then deliver the processing result to the user after computation and analysis by a large system composed of multiple servers. With cloud computing technology, network service providers can process tens of millions or even hundreds of millions of pieces of information within several seconds to achieve the same powerful network services as "supercomputer.

The concept of cloud storage is similar to that of cloud computing. It refers to cluster applications, grid technologies, distributed file systems, and other functions, A system that integrates a large number of different types of storage devices in the network through application software to jointly provide data storage and business access functions.

If this explanation is still hard to understand, we can use the WAN and Internet structure to explain cloud storage.

Cloud Network Structure

I believe that everyone knows the LAN, Wan, and Internet very well. In common LAN systems, in order to make better use of the LAN, users need to clearly know the model and configuration of each software and hardware in the network, such as what type of switch is used, how many ports are there, what routers and firewalls are used, and how they are set. The number of servers in the system, the operating system and software installed respectively. What type of connection cable is used between devices, and what XML is allocated: lang = IP address and subnet mask.

However, when we use wide area networks and the Internet, we only need to know what access networks and user names and passwords are used to connect to wide area networks and the Internet, you do not need to know how many vswitches, routers, firewalls, and servers are in the WAN and Internet. You do not need to know what routes the data is routed to our computers, you do not need to know what software is installed on the servers on the network, or what connection cables and ports are used between devices on the network.

Wan and Internet are completely transparent to specific users. We often use a cloud-like image to represent Wan and Internet, such:

Although this cloud map contains many vswitches, routers, firewalls, and servers, it is not required for specific Wan and Internet users. This cloud image represents the interconnected network service that the Wan and the Internet bring to everyone. No matter where we are, we can use a network access cable and a user and password, you can access the Wan and the Internet and enjoy the services that the network brings to us.

Refer to the cloud-like network structure to create a new cloud-like storage system consisting of multiple storage devices, work collaboratively through cluster functions, distributed file systems, or similar grid computing functions, and provide users with certain types of storage services and access services through certain application software or application interfaces.

 

 

When we use an independent storage device, we must be very clear about the model, interface, and transmission protocol of the storage device. We must clearly know how many disks are in the storage system, the connection cables used between the storage device and the server must be clear about the model and capacity. To ensure data security and business continuity, we also need to establish a data backup system and a disaster recovery system. In addition, it is also necessary to regularly monitor, maintain, update and upgrade the status of storage devices.

If cloud storage is used, everything mentioned above is not required for users. All devices in the cloud storage system are completely transparent to users. Any authorized user in any place can connect to cloud storage through an access cable, access cloud storage data.

Cloud storage is not a storage, but a service

Just like cloud-based Wan and Internet, cloud storage does not refer to a specific device, but to a collection of many storage devices and servers. A user uses cloud storage instead of a storage device, but a data access service provided by the entire cloud storage system. Therefore, cloud storage is not a storage service, but a service.

The core of cloud storage is the combination of application software and storage devices, and the transformation from storage devices to storage services is achieved through application software.

 

2. Structure Model of cloud storage

Compared with traditional storage devices, cloud storage is not just a hardware, it is a complex system consisting of network devices, storage devices, servers, application software, public access interfaces, access networks, and client programs. Each part focuses on storage devices and provides data storage and business access services through application software. The structure model of the cloud storage system is as follows:

 

The structure model of the cloud storage system consists of four layers.

I. storage layer

The storage layer is the most basic part of cloud storage. Storage devices can be FC Fiber Channel storage devices, IP Storage devices such as NAS and iSCSI, or DAS storage devices such as SCSI or SAS. The number of storage devices in cloud storage is usually large and distributed across different regions. They are connected to each other through the WAN, Internet, or FC Fiber Channel Network.

The storage device is a unified storage device management system that enables logical virtualization management of storage devices, multi-link redundancy management, and hardware equipment status monitoring and fault maintenance.

2. Basic management:

The basic management layer is the core and most difficult part of cloud storage. Through technologies such as clusters, distributed file systems, and grid computing, the basic management layer enables collaboration among multiple storage devices in cloud storage so that multiple storage devices can provide the same service externally, and provides greater and better data access performance.

The CDN content delivery system and data encryption technology ensure that data in cloud storage is not accessed by unauthorized users, various data backup and disaster tolerance technologies and measures can ensure that data in cloud storage is not lost, and that the cloud storage itself is secure and stable.

3. Application Interface Layer:

The application interface layer is the most flexible part of cloud storage. Different cloud storage operators can develop different application service interfaces based on their actual business types to provide different application services. Such as the video monitoring application platform, IPTV and VoD application platform, network hard disk reference platform, and remote data backup application platform.

4. access layer:

Any authorized user can log on to the cloud storage system through standard public application interfaces and enjoy the cloud storage service. Different cloud storage operators provide different access types and methods.

 

3 technical prerequisites for cloud storage

From the above cloud storage structure model, we can see that the cloud storage system is a collection of Multi-device, multi-application, and multi-service collaboration. Its implementation must be based on the development of multiple technologies.

I. development of broadband networks

A real cloud storage system will be a massive public service system distributed across multiple regions throughout the country or even around the world. users need to connect to cloud storage through broadband access devices such as ADSL and DDN, instead of directly connecting to an independent, private storage device through an FC, SCSI, or ethernet cable. Only when the broadband network is well developed can users get enough data transmission bandwidth to transfer massive volumes of data and truly enjoy cloud storage services. Otherwise, they can only talk about it.

Ii. Web2.0 technology

The core of Web2.0 technology is sharing. Only through the Web technology can cloud storage users use PCs, mobile phones, mobile multimedia, and other devices to centrally store and share data, documents, images, audios, and other content. The development of web technology makes users' application methods and available services more flexible and diverse.

Iii. Development of Application Storage

Cloud storage is not only about storage, but also about applications. Application storage is a storage device that integrates application software functions in storage devices. It not only has data storage functions, but also has application software functions. It can be seen as a collection of servers and storage devices. The development of application storage technology can greatly reduce the number of servers in cloud storage, thus reducing system construction costs, reducing single point of failure and performance bottlenecks caused by servers in the system, and reducing data transmission links, provides system performance and efficiency to ensure efficient and stable operation of the entire system.

Iv. Cluster technology, grid technology, and Distributed File System

A cloud storage system is a collection of multiple storage devices, applications, and services. A single point of storage system is not cloud storage.

Since it is composed of multiple storage devices, different storage devices need to use the cluster technology, Distributed File System and grid computing technology to achieve coordination between multiple storage devices, this allows multiple storage devices to provide the same service externally and provide greater and better data access performance. Without these technologies, cloud storage cannot be implemented. The so-called cloud storage can only be an independent system and cannot form a cloud structure.

V. CDN content delivery, P2P, data compression, deduplication, and Data Encryption

CDN content delivery system and data encryption technology ensure that data in cloud storage is not accessed by unauthorized users. At the same time, various data backup and disaster tolerance technologies ensure that data in cloud storage will not be lost, ensure the security and stability of cloud storage. If data security in cloud storage is not guaranteed, no one dares to use cloud storage. Otherwise, the stored data will not be lost soon, or the whole country will know it.

Vi. Storage Virtualization Technology and storage network management technology

Cloud storage has a large number of storage devices distributed across different regions. How can different vendors, models, or even different types (such as FC storage and IP Storage) be achieved) the logical volume management, storage virtualization management, and multi-link redundancy management between multiple devices will be a huge problem that cannot be solved, storage devices will be the performance bottleneck of the entire cloud storage system, and cannot form a whole structure. They will also cause problems such as difficulties in capacity and performance expansion in the future.

Another problem caused by the large number of storage devices in cloud storage and the wide distribution of regions is the operation and management of storage devices. Although these problems do not need to be concerned by cloud storage users, for cloud storage operators, however, it is necessary to solve problems such as difficult centralized management, difficult status monitoring, difficult fault maintenance, and high labor costs through practical and effective means. Therefore, cloud storage must have an efficient centralized management platform similar to network management software, allows you to centrally manage and monitor storage devices, servers, and network devices in the cloud storage system.