Network storage is still a new, if not nascent, phenomenon in India. Until few years ago, storage here was virtually synonymous with DAS-disk attached
storage.

Not long ago, DAS accounted for almost 70 percent of the storage market, while network storage made up for the remaining 30 percent. It's expected that by the end of this year, the market will be equally divided between the two.

DAS is nearly a commodity now. On the other hand, network storage continues to be driven by innovation, which means value for enterprises. At the same time, as computers-and computing-get increasingly networked, more and more storage gets onto the network. Analysts predict that by 2008, 80 percent of the external storage market will be through network storage.

Let's look at some more data.
According to IDC, in third quarter of 2004, network attached storage (NAS) accounted for 19 percent of the overall network storage market. The market research firm also estimates that by 2007, IP storage area networks (IP SANs) will account for 23 percent of the overall storage market.

Enterprises can draw plenty of inferences from the above. One, it's time to start evaluating network storage technologies seriously, if one is not doing that already. Two, among various network storage techs, IP SAN is growing at a faster pace and deserves a closer look. But first a look at enterprises' concerns regarding network storage:

Issues and Challenges
Picking up the best network storage solution remains a multi-pronged challenge for IT managers in India. Not only should the solution be able to future-proof needs of various enterprise-wide applications, but also keep the budgetary limitations in view.

In fact, high costs of Fiber Channel SANs have been one of the biggest deterrents to their wide-scale adoption in India.

An obstacle that many IT managers are facing is the inability to manage their DAS connections. Since DAS systems are unable to be networked together easily or efficiently, they are not capable of supporting a company that uses multiple enterprise-wide applications, such as ERP, CRM and SCM.

To overcome the lack of scalability and networking within DAS environments, many companies are looking at network storage solutions-SANs or NAS. By networking together a company's information assets, NAS and SANs enable scalability without excessive manual intervention in support of enterprise applications.

However, enterprises are often faced with some typical questions here. Does one need to store all data generated across the enterprise on the network? Which systems are suited for critical applications like ERP, business intelligence, etc.? What will do for applications like e-mail? And so on and so forth.

Security is a big concern of IT managers when it comes to network storage decisions.

Networked storage helps enterprises speed access to data and reduce administrative overhead, but can leave critical data vulnerable. Without the physical separation provided by traditional direct-attached storage, data assets become co-mingled in both NAS and SAN environments, putting them at much greater risk for unauthorized access, theft or misuse.

Technologies like firewalls and intrusion prevention systems seek to secure enterprise assets by protecting the perimeter of the network, but these approaches leave data at the storage core dangerously open to both internal and external attacks.

Solutions and Trends
In the last three years, one has seen DAS give way to networked storage, creating the foundation for the next phase of the evolution: intelligent storage networks. As far as network storage, particularly SAN, was concerned, price-point was one of the biggest concerns for most of the Indian users.

Organizations that haven't yet implemented any kind of networked storage or have implemented only NAS would see a lot of sense in maintaining a common networking infrastructure to serve their file-based and block-based data.

For SMEs, iSCSI offers an excellent value proposition. For larger enterprises that have already implemented FC SANs in their data centers, it can co-exist with the FC SANs and complement them.

For example, a bank may choose to run its core banking applications on FC SAN and run all midsized and smaller databases on iSCSI. Almost all organizations will see value in iSCSI SAN as it helps achieve tremendous RoI. Implementation of FC-SAN is costly, confining it to data centers.

iSCSI attempts to solve many of these problems. It leverages on two standard protocols, SCSI and IP to create another standards-based protocol. The iSCSI protocol has been ratified by the IETF as a standard and therefore it attempts to eliminate all compatibility issues.

Today, compliance regulations, new application development and focus on operational expense reduction are driving the growth of SAN. With technologies around SAN becoming more affordable, early movers are not restricted to big enterprises and SMEs are also going in SAN solutions.

Storage vendors have responded to the pricing needs of Indian enterprises and launched new versions of their network storage systems. These include systems with iSCSI and fiber channel supports, and models suited for needs of large data centers as well as SMBs.

IP gains momentum: IP-based storage has attained increased prominence at the enterprise level because of the cost factor. It helps in total network storage consolidation of storage resources at a lower cost and centralizes the storage architecture. It also helps in leveraging existing investments in fiber channel SAN.

In case of NAS it extends NAS consolidation capabilities to include traditional block applications.

It may not viable for enterprises to invest in fiber channel connectivity for all the servers as every fiber channel card/host adapter card would cost a few thousand dollars. In such cases, it is cost-effective to connect the smaller servers through IP as the IP card is available for just a few hundred dollars.

Having said that, fiber channel has superior performance over iSCSI, though the latter is more economical.

NAS versus SAN: Fundamentally, NAS and SAN are two types of technology. SAN accesses information at the block level, while NAS does it at the file level. So both have specific strengths and hence are used for specific purposes.

Typically, a SAN is implemented for mission-critical systems like ERP, while a NAS is deployed for R&D or in software development environments. Also, NAS does have a cost advantage and has a higher adoption rate among a large number of SMEs who place more emphasis on file sharing and are not using high performance applications.

SAN-NAS consolidation: A strong trend in the storage market is that customers are moving towards an environment where both NAS and SAN co-exist. While one would not want to replace a SAN on which mission critical applications like ERP, CRM run, one would like to add NAS like flexibility to the SAN. NAS gateways are an answer to this need.

NAS gateways are essentially NAS headers that allow NAS functionality on a SAN.

Having either NAS or SANs or both as an information management infrastructure enables companies to deploy their own business continuity solution with little effort, because networked data can be more easily be shared across the enterprise, even between remote sites used to replicate and back up data.

Deployment Considerations
As IP-SANs are the wave of the future, any organization that is planning to deploy an FC-SAN today should strongly consider a migration plan to ensure that their technology are not rapidly obsolesced.

Towards that end, it is recommended that IT buyers look at a profile of their data. If an IT buyer has a significant amount of mission-critical data (more than 20 percent), they should consider a FC SAN to protect it as the cost-benefit tradeoff becomes somewhat palatable at this point. Typically, 80% or more of data in an organization is not mission-critical.

The recommended approach is to create a tiered architecture based on data classification. So mission-critical data is placed on high-performance, highly survivable solutions such as IP or FC-SANs, which is the first tier. Business-critical and important data is placed on affordable IP-SAN solutions that utilize lower performing disks and offer lesser redundancy. That's the second tier. The last tier that supports non-critical data can be on a lower cost NAS.

Services are an important aspect to consider. In the coming years services, which include not only providing support and management but also planning, consulting, implementing and integration of solution will become a key differentiator.

NI/SI Has a Role to Play: Depending on the complexity of the environment and the business needs, multiple players may need to be involved. For a highly complex environment with heterogeneous SAN solutions, the SIs/NIs should take the lead because they have the integration experience to get all the components working and properly tuned. For pure IP-SAN environments, it may be acceptable to have only the vendor involved in a professional services capacity.