Benjamin Kuo is a senior product manager at Troika Networks. Troika is involved with the FAIS effort and its chief software architect, William Chow, is secretary of the T11 FAIS standard group and an active member of the FAIS group. Benjamin Kuo is familiar with the FAIS effort and was involved in its early stages, as well as having been involved in a number of other storage industry standards. Techworld asked him some questions about the FAIS topic.

1. Why have storage applications in the fabric?

"There are many reasons to put storage application in the fabric, including centralized access to resources; easier management; and streamlined deployment. One of the biggest is the ability to manage heterogenous equipment in a single, unified way--making it possible to deploy things like data protection across a mixed storage and host environment with a single tool."

2. What are storage applications? What do they do? Where does their ambit stop and server-based applications with storage functionality start?

"Storage application include traditional data protection applications like snapshot, mirroring, and replication. These data protection applications are used to help create disaster recovery sites, make it possible to do zero-window backups, and also for things like creating copies of data for testing and data warehousing. It also includes applications like storage virtualization and volume management, which helps create a centralized storage pool across heterogenous storage; and can also includes applications like continuous data protection and information lifecycle management."

"For those who aren't familiar with snapshot, it's the ability to create an instantaneous snapshot of data at a point in time on disk; this is done through a copy-on-write implemented in either software or hardware, and allows an administrator to quickly quiesce the application or database they are running, make a snapshot, and then do a backup from the snapshot offline. Snapshots can also be handy for instant recovery of data in case of user error or corruption."

"Mirroring and replication is the ability to create two copies of data on separate physical locations; this can either be done locally or even across a long distance link to another data center. Users have traditionally used this for protection against disk failure, but we find our users are mostly using this for disaster recovery."

3. How does FAIS provide a level playing field for fabric applications?

"FAIS (the Fabric Application Interface Standard) is an effort to create a common application programming interface (API) for fabric applications to run on an underlying hardware platform. This application interface is a standard way for software to run on any FAIS-compliant platform, allowing them to write their software once and easily support all hardware. The development of a common API makes it drastically easier for fabric applications providers to support a wide range of hardware without expensive and time consuming porting efforts. Althought applications will still need some porting, because the API is compatible the amount of effort should be far less than trying to port between proprietary interfaces."

"With FAIS, providers are able to take advantage of new split-path acceleration (SPAID) capabilities of new hardware platforms, without having to know the proprietary details of every platform. It's really intended to accelerate development of applications for independent software vendors (ISVs) who are interested in fabric-based platforms."

4. Is FAIS all that is needed for a fabric application supplier to produce software that will run on intelligent fabric platforms?

"When finalized and ratified, the FAIS standard should provide almost everything an application supplier would need to produce software running basic volume management in an intelligent fabric platform, in addition to the intelligent fabric platform itself. The standard covers things like storage pooling and backside multipathing."

"It's likely that there will be some amount of support by individual FAIS-compliant vendors to ease the process for software providers, however, in general applications that are FAIS compliant are expected at this time to run on all FAIS-compliant platforms."

"However, one area which isn't covered by the FAIS standard is non-SCSI related functionality, such as basic operating system services like threading and transport-specific functionality such as Fibre Channel name services."

5. Will there be and should there be a standard interface for server applications/ operating systems to use when requesting storage services from a fabric-based storage application service?

"That's an interesting question. It's fairly difficult to do this right now because of the numerous ways of deploying storage applications, however there are efforts underway in the Storage Networking Industry Association (SNIA) with the Storage Management Interface Specification (SMI-S). That effort includes modeling of virtualization and other network services and the ability query and manipulate storage services for disks and virtualizers. It's still a bit early to see how providers and management providers will tie in fabric-based applications since it's an emerging market."

6. Where do NAS and iSCSI fit with FAIS?

"The FAIS standard was developed as a transport-independent protocol, initially targeting Fibre Channel but extensible to other protocols like iSCSI. We haven't seen any movement yet to provide FAIS APIs on iSCSI, but the standardization effort is still young and intended to cover other SCSI storage protocols. In terms of NAS, FAIS can be used by NAS hardware, but does not cover NAS virtualization."

7. Who will provide FAIS-compliant hardware?

"Currently, along with Troika Networks, the companies involved in the FAIS standards organization and providing FAIS-compliant hardware include Cisco Systems, Brocade, and McData, as long with others. Troika is shipping its products into the market today, and has deployed end customer solutions at numerous end customer sites. We also have provided our hardware to a number of ISVs who already have ported and demonstrated their applications running on our existing application interfaces. Those interfaces are being incorporated as part of the FAIS specification development as part of the standards development process. We also intend to provide FAIS-compliant hardware when the standard is ready for implementation."