A few years ago, Steve McCanne Ph.D. Professor at the University of Berkeley in the United States during the present a bold vision - to LAN (local area network) and WAN (wide area network) to distinguish.
Dr. McCanne Why is this idea? Original, beginning in the design of wide area network and remote file services have not too much to consider. With the development of wide area networks, more and more reflected the problems: one is bandwidth, one is reliability, as well as delay. These three aspects are not well resolved WAN, the data for the user to provide remote services, file services, in particular, the efficiency is very low. So, Dr. McCanne this academic researchers solemnly recommendations: LAN and WAN distinction.
Good idea, but from the realization of the project is too complex and would be an astronomical cost. Therefore, many researchers several years ago on the set of optimized WAN things, some new companies have invested in R & D related products. Today, these ideas have become reality, this is the recent flurry of WAFS (Wide Area File Services, wide area file services).
WAFS market first by industry analyst Taneja Group definition. The emergence of this market is mainly distributed in order to maintain operations to meet the needs of enterprises, because in a distributed operations, many users need to interact across multiple locations. Remote offices in expensive infrastructure costs and the rapid increase in overseas development, business integration and business expansion into new areas of opportunity around the world, the need to promote the rapid development of wide-area file services.
According to incomplete statistics, there are more than 120,000 distributed global enterprises and more than 4 million remote offices. These users need to improve the performance and reliability of remote offices to easily achieve real-time enterprise-wide file sharing, these are wide-area file services you should be rolling in the huge market.
WAN file services, three major problems facing
Delay in the WAN every file saved or opened that could spent up to several minutes, sometimes even unable to successfully complete the operation. In the WAN to open or save a basic file operations may contain thousands of individual WAN "from" communication process, the so-called remote procedure call, referred to as RPC. As the wide area network delays caused by network latency than LAN access time is much higher (usually sophomores to four times), but as CIFS (Common Internet File System) and NFS (Network File System) like file-sharing agreement does not may deal with high delay network environment. Each time the CIFS or NFS protocol in the WAN created "from" will result in higher communication delay, and the enormous impact performance. As the distance between two points in the WAN and network contention increases, the network will be an even greater delay, but the problem would be more intensive.
Lack of reliability in open and save in the process of file data is likely to unlimited "overtime." The updated document may also be in the process disappear for no reason. WAN LAN connection reliability are inherently worse than the many, often in the case packet loss, network outages sometimes occur (especially the use of satellite or microwave link technology).
Low-bandwidth low-bandwidth remote access to files may produce unbearable to low. This may lead to remote users with a number of compromise, these should be at the center of the original files on the server to a local file share or directory and edit it. The compromise would create many problems in the future, such as multiple versions of the same file will appear, and the redundancy of data scattered throughout the enterprise, is difficult to implement effective management. Usually performance, the enterprise branch office WAN bandwidth used by the LAN bandwidth is lower than 10 to 100 times, the main connection for the T1, DSL or frame relay connections, and these connections can basically meet the requirements of the remote file request . If you want to add in the wide area network connections and other network layer VPN, there may further reduce the WAN bandwidth.
WAFS works
To solve the above problems, WAFS product came into being. Typical WAFS architecture consists of two components: a main data center is located within the WAFS server equipment, and in remote locations, one or more remote devices. WAFS devices each CIFS and NFS, etc. by standard protocols with existing remote client PC machine and file server for communication, and use the WAN-optimized custom protocol for communication between these devices. Use of these custom protocols and optimization, WAFS to WAN and from the elimination of redundant communication, that is, RPC, RPC is the wide area network which delays the culprit behind.
In the data center, WAFS server device looks like installed in the primary site within a shared network attached storage (NAS) device to another client, the user will WAFS device as a remote network file sharing functionality with NAS devices. WAFS solution can be many ways to solve the wide area network of the three major issues, namely, delay, reliability, and low-bandwidth network. Best of the WAFS devices typically perform very complex read / write buffer algorithm, and uses data compression and data streaming technology, enabling users and files will not be the majority of common wide area network problems. Some WAFS systems can also perform a distributed file locking, and further ensure data integrity and consistency, that is, users can only view and edit a central server to the latest version. By combining these technologies and methods, we can effectively become a global wide area network LAN, employees around the world can feel free to visit and use the same file.
Bring the benefits of WAFS Five
Comprehensive seems, WAFS from the following aspects of great benefit to users.
1. Replace or reduce existing remote storage server, hardware and software.
A WAFS device can replace multiple remote file servers, remote backup hardware (tape drives, etc.), backup tapes, backup software, management software, DNS / DHCP name server, Web cache server, print server, the server operating system-related license / upgrade protection programs, as well as antivirus software and server-related licensing. These have contributed to the remote storage island combined with the main data center.
2. For all forms of enterprise data management to implement a more centralized.
For remote office locations faster and more comprehensive data protection and business continuity protection, more faithful implementation of compliance standards, IT staff need to monitor remote backup and remote server hardware or software upgrade process. In addition, companies no longer need to rely on remote office file storage capacity, WAFS also enables enterprises to simplify and remote sites related compliance strategies and to ensure higher data availability. Edge data are realized as centralized management, IT departments can also implement a broader policy-based management and archiving.
3. Reduce the remote office IT infrastructure and reduce maintenance costs.
WAFS facilities no longer needed because the remote IT operations, and therefore it can save IT manpower and travel costs, while the electricity consumed by the remote system will be substantially reduced. These offices can also cancel a number of remote hardware and software maintenance contracts for the enterprises to further reduce the cost of operating the process.
4. Significantly improve the productivity of remote users.
Many remote users are used to access files over the WAN to wait a long time, but now, they get close to access documents and files of LAN capabilities, as if the whole process is like to achieve through the internal LAN access.
5. Improve collaboration through the global file sharing.
For those who require close collaboration of key industries, such as to produce detailed CAD drawings of the industry, WAFS to different companies and different locations of Xiaozu members to 更 quickly update file content, and a document with the Shang Xietonggongzuo. Responsible for the implementation of WAFS in the corporate IT department can more comfortably be transformed into a unified wide area network, global LAN and global real-time sharing of data.
Unlike WAFS WAN Accelerator
Reporter encountered such a situation, many manufacturers and users of the engineers on the WAFS and WAN accelerator mixed up the concept. Of course they are both vague concept is understandable, because they are the main techniques used to solve the problem, and a large part of the same, but their differences are very obvious. The main purpose of WAFS for storage and server consolidation and thus saving the user valuable storage space, while the WAN accelerator is focused on investments in reducing the wide area network and the effective use of expensive bandwidth. Both can be effective remote data transmission.
WAFS and WAN Accelerator Comparison List
Technical characteristics of the main objectives of their
WAFS to LAN speed WAN data transmission;
Servers and storage devices integrated with multi-site replication between the cache to ensure consistency;
Virtual disk to minimize downtime
WAN Wide Area Network Accelerator to improve performance;
CAPE pin to reduce WAN bandwidth, packet loss, or the effective use of the service will not be affected;
At a slower pace in the WAFS;
No server and storage consolidation
Users to consider eight factors
In a number of vendors to get information, reporters found that they all claim a lot of advantages, but only from the text difficult to distinguish the difference between these products, then press summed up the following eight questions that the users get all these issues The answer after the selection of WAFS products will be more confident.
1. WAFS performance
WAFS solution should be able to demonstrate a similar LAN WAN capacity for continuous operation. The performance of typical problems include: WAN open / save a single file of the performance? When dealing with large file performance? Processing of metadata, or CIFS / NFS directory listing when performance? Open and Save "cold" documents and "hot" documents the performance? What mechanism or system uses algorithms to reduce the data sent through the WAN traffic, and save or open the operation to complete the remote procedure call the amount of data required? The solution used by enterprises in the face of the majority of users file type performance? The solution is able to handle all of the same file types?
2. System reliability and flexibility
WAN communication has always been prone to break on, and poor quality of the connection, resulting in the performance of the network connection was seriously damaged. The following questions can help you determine the WAFS system in the face of WAN performance problems in the end how high. They can also help determine WAFS vendors in the end the measures taken to deal with all kinds of faults: In order to ensure that the remote user's actions or documents are not affected, WAFS system is how to deal with wide area network connection interruption or poor quality problems? When the WAFS main connection to the server outage, remote users still can access the remote file? If you can access it, in the end is how to achieve it? When the wide area network outage occurs, the WAN is in a state of open files or store which will be affected? File cache or compression to the extent to which improve the system after a fault in the wide area network resilience? This feature functions with other vendors how much difference? If a component WAFS hardware failure, the system can provide what security features to ensure ongoing access is not affected (such as the cluster capacity, RAID, fast failover support, etc.)?
In order to meet the wide area network disruptions, WAFS vendors to take a variety of methods to ensure users are fully capable of WAN open, close, or save the file without losing data.
3. Data integrity
When multiple users in multiple locations through the wide area network to share the same files, they are most concerned about is the integrity of the data. In short, WAFS solution must be able to ensure that all documents are the latest version, and can not be more than one user to edit. Provided below in this regard is worth considering several questions: How can the system ensure that all sites can be coherent view of data? System used by the file locking mechanism to ensure that each has only one user can edit the file? When someone is editing a file, other users can view the file from multiple locations? If so, this practice will reduce the performance of file access? If a remote user to open and use a file occurs when a network disruption or downtime event, the system is by any means to prevent file damage?
4. Data security
Since file access edge in business location, WAFS system needs to have built-in security features to ensure that only those who really need access to these files the user to gain access. They also need to send those packets across the WAN to provide adequate safety barriers. Security problems include the following few: WAFS solution is used in what type of encryption? The user has some files in the enterprise environment implemented role-based access control, WAFS system to support such access control rules about performance? Safety rules are adopted to manage the centralized WAFS servers still need users to use remote WAFS device to collaborative management? When the user needs to access files, WAFS system is how to help business users to implement authentication and authorization? Whether this process is automatic? This process took place located? In order to achieve the purpose of tracking file access mode, WAFS system what type of log or review function?
5. WAFS scalability and expansion capability
WAFS in the discussion, many users are very interested in an issue of whether there is a solution which can be expanded to accommodate more concurrent remote users, and more remote sites. Users also learn about the WAFS solution is to expand and focus beyond their final use file sharing and consolidation. In this regard, several issues worth considering the following: use of WAFS solutions, the number of remote sites can be incorporated into the data center? In other words, a focus on WAFS server can support the number of remote sites? When added to the WAFS system, remote site, whether in the data center for each office or each file to add additional storage resources? WAFS can use the number of remote sites into the data center? Remote offices to access data center resources shared storage quantity of the existence of access restrictions? WAFS system can support at a remote site, how many concurrent users? As the WAFS system can replace other remote server, then it can support the other branch office services, such as print services, Web caching services, managed services, or DNS / DHCP services?
6. Integration and protocol support
WAFS any robust solutions with all major operating system platforms can use file transfer protocol to establish perfect communication. Typical in this regard include: the system supports Linux or Windows environment, file access capabilities? The system uses what technology to integrate the existing environment CIFS or NFS protocol? In the Windows environment, WAFS system (through NetBIOS, WNS, DNS) name resolution to support the ability to function? The system supports SMS (Systems Management Server) and Active Directory's capabilities?
7. System management and ease of use
WAFS system's ease of use in the management of assessment is a key factor. Therefore, in the assessment process should take into account the following issues: whether the simple installation process? What need to perform routine system management functions? Implementation of these features require more long? The system can provide for all remote WAFS device centralized management control? If you can provide, so remote office locations in which a management capacity needs? The concentration of WAFS system and the data center may be used in large system management tools (such as IBM / Tivoli, HP OpenView, and Microsoft SMS, etc.) how good integration capabilities? In the Microsoft Windows environment, WAFS system and Active Directory, SMS, Microsoft Management Console (MMC) and Microsoft Operations Manager (MoM) and other Microsoft management tools, integration abilities?
8. The practical application of test
In consideration of these seven areas after completion, the user can basically have an overall understanding of WAFS products. Reporter recommended prior to purchase should also be combined with the practical application of their own environmental testing something. For example, WAFS vendors selling products to customers generally have some nice test report. The long-term test tells reporters, these tests ends up on the specific test environment were obtained, and some tests small samples of the special adjustment Huozhe user applications will jack Juti the actual Gongzuo undergoing dramatic changes in performance, users After a period of time the actual trial will be the most convincing results.
Although WAFS to the wide area network without any substantive change, but through the WAFS products for remote file service has undergone a fundamental change. After years of development, the current WAFS products (probably the fourth generation) has been basically mature. In the past several generations of products through distribution to focus on from the changes, previous generations of WAFS trying (usually unsuccessfully) to achieve a fully distributed data model. Currently almost all products have moved to centralized storage, greatly reducing the need to support remote users of software and hardware.
WAFS separate price is not high, but users can not WAFS products as an isolated view, only it into a more integrated and comprehensive data center solutions can play a greater role, as more users good return on investment. Thus, it is providing remote file sharing, or to carry out the integration of servers and storage devices, WAFS less like a simple single product. Through the promotion of models of various manufacturers, it was generally by way of providing total solution to enter the market.
There are a number of manufacturers introduced a WAFS product, but it brings a wider range of memory consolidation may be just beginning, the user has been granted the original backup, disaster recovery, storage and other routine work are likely to have a significant impact. For example, in the absence of prior WAFS users for remote backups work great challenge, to face a lot of bandwidth, delay problems, but to deploy WAFS product, would greatly reduce the amount of data remote transmission. Similar to the advantage of enhancing the value of storage networking users to deploy WAFS products may be more apparent later.
WAFS News
■ Brocade: concern shared storage
Brocade Tapestry products launched recently, concerns from the previous extended SAN network equipment to a wider range of shared storage environments. In addition to WAFS products, the Brocade Tapestry products include ARM (Application Resource Management), and DMM (Data Migration Manager). Brocade WAFS products can be achieved through the WAN file transfer speed LAN, WAN, on shortening the time consumed by file transfer, WAFS has achieved Microsoft certification, and has been recognized by the market.
Brocade is a leading WAFS vendor Tacit through cooperation by the WAFS products, in addition, Brocade is also investments on Tacit. Then the future will not buy Brocade Tacit it? When a reporter asked about Brocade vice president on the issue Daibodata, the answer is, "Time will tell us the answer."
■ McDATA: NAS can also be connected
Large part of McDATA customers are large data centers, in addition to their demand for SAN connectivity, the NAS there is equally remote connectivity needs.
McDATA Lei Tao, China Technical Manager, said, in large user data disaster recovery applications, some log files, configuration files working on the reproduction of the original cases through professional services (such as manual preparation of the script) to achieve, while conducting high-level business continuity program, through WAFS and other related services to remote files, can make remote data disaster recovery as a local disaster recovery.
McDATA disclosed in the next two months will be issued WAFS product, and not confined to the WAFS, the also includes a remote data service related solutions.
■ RiverBed: to provide wide-area data services
RiverBed hing, general manager of Greater China companies introduced products with other vendors only WAFS different, RiverBed solutions for both the WAFS products, but also includes WAN accelerators, so can provide users with remote data services. By optimizing WAN interact, RiverBed Steelhead products to improve WAN application performance, enabling the vast majority of IT equipment in remote offices into a single centralized data centers to help users achieve the so-called "no server office."
■ Cisco: joint EMC
Cisco last June by 82 million U.S. dollars acquisition of Actona WAFS companies enter the field early this year, Cisco announced a partnership EMC's NAS products, said the consignment and Cisco will support EMC's Celerra NAS products. Recently, Cisco announced it will sell its WAFS WAN file services, application integration engine to the EMC NAS.
Obviously, Cisco WAFS products on the integration of the user aware of the importance of NAS, the NAS market share with the current EMC cooperation for their first business will be carried out WAFS great promotion.