SAN Appliances: Enabling Media Rich Internet Storage Networks.

The promise of the Internet is being unlocked. With massive bandwidth and storage capacities readily available and desktop computers, PDAs, cell phones, and TVs linked like never before, second-generation Internet applications are poised to harness the potential of worldwide data access. Led by streaming media, interactive e-business, and content delivery, these next generation Internet applications promise to bring real world data to individuals and workgroups to make the Internet an indispensable part of life. Yet before users embrace ubiquitous data access, Quality of Service and "user experience" must equal that delivered by over-air or cable systems.

These requirements for Quality of Service (QoS) and user experience are forcing a revolution in Internet, as well as corporate infrastructures. Consequently, streaming media and content delivery companies, as well as Fortune 500 and "brick and mortar" firms, are developing next generation infrastructures, specifically "core-edge" deployments. With this distributed peer-to-peer topology, firms can bring content closer to the user, increasing the quality of user experience and customer interaction (Fig 1).

Network architects and storage professionals designing these next-generation infrastructures are looking to Storage Area Networks (SANs) to play a critical role in meeting these QoS demands as they create "content-centric" Internet Storage Networks (ISNs). More specifically, these Internet Storage Networks are looking at the positive impact that "disruptive" SAN technologies can bring to their operations.

This "core-edge" transaction/content management design allows for one-to-one trust relationships enabled by SANs. A distributed peer-to-peer high-bandwidth Internet Storage Network infrastructure would provide:

* High-performance Internet content delivery.

* High I/O connectivity enabling e-commerce.

* QoS without performance loss.

* Fortress-like security.

* Scalable shared resources.

* Uninterrupted user interaction.

* Reduced network and storage costs.

* Reduced acquisition, implementation, and operating costs.

* Critical data monitoring, reporting, and analysis.

"Core-edge" infrastructure deployments were conceived to meet the explosive growth and demands of streaming media, as well as interactive e-business and content delivery, but implementation has proven to be a challenge. Internet content, more specifically media-rich content, covers a tremendous range of file sizes, formats, and performance requirements. Changing from a traditional mix of text and numbers to one that now includes images, sound, and video has rendered current network storage technology outdated. Consequently, content delivery and other IT professionals are faced with the prospect of creating infrastructures using earlier, outdated technology that is difficult and costly to customize for their specific and typically wide-ranging data delivery requirements.

We need to explore the concept of network storage and data accessibility through its evolutionary progression to meet the needs of streaming media and content delivery. We need to explore creating a high bandwidth flexible infrastructure that pools, shares, and scales resources enabling a next generation infrastructure, while reducing acquisition, implementation, and operation costs. We must recognize that if "brick and mortar," "click and order," or streaming media enterprises are to be successful, they will need to access data from a variety of storage media and stage it on the edge of the Internet at high-speeds without degrading QoS.

Media-Rich Internet Storage Networks

Internet Storage Networks have been conceived to meet the tremendous growth and demands of e-commerce, streaming media, data mining, and online transaction processing. These factors are the driving force behind petabyte-class core data repositories and multi-terabyte edge sites that more than double in size every quarter. As stated before, the nature of this data has changed from text and numbers to now include images, sound, and video. This data explosion and change of data has altered how worldwide infrastructures deliver data--elevating the management, sharing, distribution, and protection needs of storage infrastructures--while the heterogeneity of storage and server hardware places even further demands on the IT professionals charged with managing these resources. With this new mix of data in a large, non-deterministic distributed world, the classic Fibre Channel and SCSI direct-attached storage, "hands-off" proprietary closed systems, and Ethernet Network Attached Storage (NAS) solutions have reached th eir limits in scalability, performance, connectivity, and management capability.

Roadblocks

Web architects and Internet administrators face a myriad of potential roadblocks in implementation content-centric infrastructures with "hands-off' proprietary closed systems and Ethernet Network Attached Storage (NAS) technology. For example, with "hands-off' multi-million dollar closed systems, flexibility, scalability, and performance are expensive and limited. Once a system is installed you must receive permission or wait for service to move or re-purpose a system. Scalability means vendor lock-in, purchasing commodity components at a premium price. Performance means adding expensive systems to deliver the number of simultaneous streams needed to adequately deliver content.

With a NAS solution in a media-rich environment, storage pooling, resource sharing, and backup are costly and inadequate. NAS solutions scale by adding additional systems with dedicated storage, but as additional servers are added, data replication techniques are employed to maintain data access. Data replication creates islands of data--under-utilizing storage assets, as well as making it difficult to manage. Furthermore, backup of numerous separate and dedicated systems over the Local Area Network (LAN) is complex, reducing backup windows, increasing restore times, as well as degrading performance on the IP network.

Even first generation SANs have their limitations. With a first generation SAN, data is streamed fairly well when dealing with a small number of web servers. Yet, as additional servers are added, streaming performance per system degrades requiring a complex addition of switches, RAID controllers, software, and disks, as well as bringing the need to employ data replication techniques to maintain data access. Moreover, today's deployments involve extensive configuration and product certification to verify that the mix of individual components will interconnect amongst themselves and the existing IT infrastructure. A change in any element of this configuration requires a complete re-certification of all the elements (Fig 2).

Managing Distributed Storage 

As a result of all these factors, organizations are forced to dedicate substantial financial and personnel resources to manage and maintain the distributed storage capabilities used to support Internet and business computing. After careful analysis, solving these issues requires a network infrastructure device that:

* Centralizes the administration of multi-vendor storage pools that can result in substantial savings in equipment and management costs.

* Enables different types of storage to be aggregated into single logical storage resource pools from which virtual volumes can be created and administered.

* Allows virtual logical units numbers to be created within shared storage pools without regard to physical configuration constraints.

* Supplies port virtualization to completely abstract applications from physical devices and physical paths.

* Virtualizes JBOD and RAID storage devices into pools of storage resources that behave like ordinary disk volumes to the operating system.

* Secures data traffic through an authentication mechanism that eliminates the need for LUN zoning and masking.

* Bridges islands of information by enabling a multi-vendor mix of computing platforms to share data.

* Continues to supply uninterrupted QoS data delivery, even after experiencing sub-system failures.

"Hands-off" proprietary closed systems, NAS, or first generation SAN cannot meet these requirements for media-rich environments simply, easily, or cost-effectively.

SAN Appliances, Creating Intelligent Internet Storage Networks

It is clear that the media-rich applications and the Internet itself will reach critical mass when users can connect directly to their data, simply, securely, and cost-effectively, while enjoying a high-quality viewing and interactive experience. The key attributes of a SAN infrastructure that enables these media-rich applications include:

* Networking capability equivalent to proven LAN technology

* Data and network intelligence

* Multi-dimensional scalability, broad, as well as deep

* High-bandwidth

* Heterogeneous shared access to data

* I/O handling capability

* Low latency transfers

* Guaranteed reliability and availability

* Protection of existing infrastructure and storage products ("legacy" systems)

Content-centric SANs designed with intelligent devices will efficiently and cost-effectively handle media-rich content and provide data management and migration with high-speed connectivity across multiple operating systems and networks simultaneously. These management functions are vital to the access, processing, manipulation, and storage of media-rich content. High-speed, shared access Storage Area Networks require dedicated connections operating at high performance levels to support the demands of large data transfers. Finally, media-rich Internet Storage Networks, characterized by a continuous stream of technology and scalability change, must be supported by a flexible and intelligent storage networking infrastructure.

Experience has indicated that a content-centric SAN infrastructure device, in other words, a SAN appliance, which is inserted directly into Internet Storage Network, meets these demands by providing:

* A high bandwidth, highly scalable open systems data network infrastructure that plugs into existing network environments.

* Simple, centralized, and secure data and network management.

* Storage virtualization and pooling to maximize the productivity of storage resources.

* Port and path virtualization to free applications from the physical constraints of direct connect or early SAN architectures.

* Sophisticated security that turns LUN zoning and masking into technologies of the past.

* Simple and efficient business continuance functions enabling continuous operation.

* Investment protection covering legacy networking and storage products.

* Reduced Total Cost of Ownership (TCO) and capital acquisition costs.

* Operating system and platform independence--with support for all major platforms available today, including Windows NT and 2000, HP-UX, Linux, Sun Solaris, AIX, and SGI/IRIX operating systems.

By comparison to a "hands-off" proprietary closed system, NAS, and even first generation SAN, an Internet Storage Network built with a SAN appliance can add servers and/or storage without bringing down the network and scaling streaming performance linearly without degrading overall system performance. SAN appliance scalability and flexibility protect against "flash crowds" and reduce user interruption, as well as providing the ability to re-purpose assets as the business grows. Adopting this intelligent network data access device, the SAN appliance reduces equipment acquisition costs, as well as dramatically reducing installation cost and delivering a lower TCO.

A fault-tolerant SAN appliance delivering storage and SAN virtualization plus data protection technology can support large numbers of data drives, reducing the need for data replication and eliminating islands of data. The benefits of pooling storage and resource sharing allow web administrators to fully utilize disk and other resources, as well as reduce the need for additional disk purchases. In addition, an intelligent SAN appliance can support JBOD (Just a Bunch of Disks) disks delivering open-systems storage support, allowing Internet and other IT administrators to take advantage of economies of scale, while eliminating vendor lock-in.

A high availability SAN appliance not only provides transparent data protection and fault resiliency but also business continuance technology enabling simple and efficient backup, restore, and archive along with disaster recovery, remote data replication, and application and data failover (Fig 3).

While this SAN device appears revolutionary by today's standards, in a few years, an intelligent SAN appliance infrastructure device--designed to provide high bandwidth and scalable access to shared data in a distributed computing Storage Area Network--can move to a standardized solution for a wide range of media-rich applications, as well as other e-business applications. In fact, one SAN appliance that is available today is optimized for the high bandwidth requirements of the Internet, easily configured for "core-edge" networks to pro-vide shared access to large volumes of distributed data.

This SAN appliance strategy offers business a better way to deploy media-rich infrastructures, creating an intelligent platform that combines all necessary infrastructure and intelligence into a single, self-contained, preconfigured, and pre-tested solution. If we examine the first of these next generation of SAN appliance products, DataDirect Networks' SAN DataDirector, we find that it offers streaming professionals all the key features mentioned above, providing them the ability to install a SAN quickly and easily; introduces scalability and flexibility into existing infrastructures; virtualizes storage for pooling and resource sharing; and provides simple and secure centralized data and network management. More importantly, they deliver high bandwidth and content availability needs for QoS operations and a high quality viewing experience. These factors deliver lower TCO and higher ROI with a compelling business advan-tage. For those without any form of SAN infrastructure, the new generation appliance is an elegant, yet complete way, to step into this powerful technology, providing all the functionality needed to deploy a comprehensive, centrally managed, fully scalable Storage Area Network and, for those with early SAN installations, RAID investments, and a base of hardware and software, they offer a powerful capability that can evolve legacy technology investments into powerful, intelligent network storage systems.

As uses for media content continue to evolve, IT professionals are finding new and significant business advantages using SAN technology. The advent of the SAN appliance provides enterprises with a flexible and scalable solution that will allow users to maximize their investments and productivity while bringing end-users richer and more dynamic experiences. With Storage Area Networks--and next generation SAN appliances--the promise of the e-century has finally arrived.

Robert Woolery is the vice president of corporate development and strategic planning at DataDirect Networks.