HPCwire: Why did you leave McDATA to start Crosswalk?

McDonnell: While still at McDATA, through experience and numerous conversations with end-users, industry experts and channel partners, one thing became very evident: a fundamental change must occur in storage systems and architectures. End-users have been demanding answers from their data to drive critical real-time business decisions and increase value in competitive markets. Yet technologies from today's vendors are not suited to deliver on this promise. End-users must choose among a hodgepodge of partial fixes and short-term “band-aids”.

These end-users are demanding storage systems that enable efficient sharing and consolidation of data and storage, compelling changes in the storage architecture and real business value. It became clear to me that the vendor that is able to meet these demands would be very successful.

HPCwire: Can you tell our readers what exactly Crosswalk does?

McDonnell: At Crosswalk, we approach technology and solution development from a unique standpoint. We believe that the ideal storage system solution does not require a forklift upgrade, or disruptive change, but does mandate new thinking about innovative grid-based architectures and intelligent networked storage technologies. We believe the industry and user expectations need to shift from “point-solutions” that only address the symptoms to simpler and more comprehensive solutions that efficiently fulfill fundamental business objectives.

In response to the needs of the end-user, we have developed the iGrid Intelligent Storage Grid System. This software-based solution is built from the ground up to meet the high-performance storage demands of computational grids and clusters in environments where productivity, results and time-to-completion are all being adversely impacted by inflexible, segmented storage architectures. Instead, iGrid is truly adaptable, enabling users to add storage capacity whenever it's needed, and to make each and every storage volume available to each and every application server and end-user. The bottom line here is that iGrid empowers collaborative project team members to focus on their work, not storage work-arounds.

HPCwire: How would you define a storage grid?

McDonnell: At a high level, a storage grid is an architecture that incorporates well-understood grid principles that enable organizations to leverage and share disparate storage resources.

As a long-time storage industry participant, I have seen the industry conquer many of the basic storage issues. But, the HPC community has presented a variety of unique challenges to the storage industry that have largely gone unanswered. This is due to the simple fact that today's storage architectures are static and inflexible, and therefore have proven themselves incapable of meeting these challenges. We at Crosswalk determined early on that in order to solve these problems, a radically new architecture was needed.  This new architecture must decouple the physical storage, and all of the physical storage challenges, from the applications to create a scalable shared infrastructure model that leverages economies of scale across the physical infrastructure. This is the premise upon which we built the iGrid Intelligent Storage Grid System.

HPCwire: Is there a difference between a storage grid and grid storage?

McDonnell: Some would argue that they are the same, just as they would argue that clustered storage is the same as grid storage. It may be just semantics, but we believe that there is a significant difference between a storage grid and grid storage. Definitions of grid storage typically involve “storage nodes”, where the node contains dedicated, self-contained storage. If this definition is taken literally, then the majority of clustered storage offerings could also be accurately defined as grid storage. In this case, if you need more storage, you add another “storage node”.

One of the key problems with that approach is that most potential customers already have a substantial investment in existing storage resources that are already not fully utilized. Furthermore, pricing of physical storage continues to decrease at a rate that suggests it should be treated as a commodity. We listened to the end-users, which led us to make a conscious decision to build an architecture that can leverage the customer's existing storage arrays. Not only does iGrid provide the customer with investment protection, it also provides storage grid services such as resource sharing and aggregation, policy-based load balancing, and automated failover and failback to create a storage grid that is linearly scalable in performance, access, capacity, and resiliency.

HPCwire: How and where are storage grids being utilized today?

McDonnell: At this point, I could argue that storage grids are not being utilized today, and this is the primary reason I founded Crosswalk.

As we discussed previously, only a new, innovative storage architecture is capable of meeting not only the demands of the HPC community, but also those of the “traditional” enterprise customer. While we continue to see widespread use of grid principles and architectures in research applications for markets like oil and gas exploration, pharmaceuticals, and manufacturing, we are also seeing an increase in the adoption of grid architectures in transaction-intensive markets such as financial services, particularly investment banks and insurers. Additionally, we are seeing increased interest from the telco market, especially with respect to billing systems and resource brokering, such as storage utility services.

HPCwire: How would an end-user purchase and implement iGrid?

McDonnell: The system is sold as a bundled system, meaning the hardware and software are priced together and not separated. Crosswalk has made a conscious decision to provide a simple pricing model in the early stages of the product, charging by the node rather than a complex charge on terabytes supported and/or by the number of servers or users supported.

Crosswalk's competitive advantage and value-add comes from the iGridOS software, which is installed on a purpose-built, commodity server. We call this an iGrid node. The hardware platform used for iGrid takes advantage of industry-standard hardware, which allows Crosswalk to leverage processor and physical interface advancements without having to perform any hardware development.

iGrid nodes are installed between application servers using industry-standard Gigabit Ethernet or InfiniBand and Fibre Channel storage using either 2 or 4 Gbps Fibre Channel interfaces. Once installed, the iGrid nodes logically consolidate all attached physical storage devices into a single, scalable shared storage resource that allows each iGrid node to simultaneously access any file system, any file, and any volume within the shared storage pool. Clients mount file systems using industry-standard NFS and CIFS protocols.

The user has a great deal of flexibility in the selection of storage for the system. Disk storage can be provided by the customer or Crosswalk can provide it as part of the system. If they wish to provide their own storage with existing hardware or if they have a preferred provider with whom they do business, iGrid doesn't require specific or proprietary disk storage. If it is more convenient for Crosswalk to provide the storage as part of the system, Fibre Channel or SATA II disk technology is made available to the customer at a competitive price.

HPCwire: Who do you see as Crosswalk's main competitors?

McDonnell: Current static and inflexible storage architectures that limit scalability and are complex to manage. While “new” offerings, such as clustered NAS, parallel file systems, and clustered storage address specific requirements well, they still rely on legacy storage architectures and principles that restrict access and sharing, create data segmentation, and do not improve storage utilization.

HPCwire: What is the company's market strategy?

McDonnell: Crosswalk's initial strategy is to focus on the high performance computing market for a number of reasons. First, most HPC users continue to struggle with how to manage large compute environments that have massive storage and input/output requirements. The creation of clustered computing and/or compute grids has made major steps forward in increasing compute power at lower costs than the previous generations of supercomputers; however, little if any progress has been made with how to effectively provide high-performing mass storage for these systems. As a result, HPC users continually look for new solutions and are much more receptive to new companies that provide unique solutions.

Service providers have also been an interesting target market because of their requirements for rapid non-disruptive storage configuration changes to meet new customer demands.
 
Data mining is another area of interest because the applications tend to be I/O intensive and can benefit from the scalability, shared storage and caching capabilities of iGrid.

HPCwire: How confident are you that Crosswalk will succeed?

McDonnell: We are looking forward to an exciting 2007 that we believe will represent a fundamental and exciting re-shaping of our industry and the value it drives for end-users and their organizations.