By Heidi Biggar
Fabric-based intelligence (i.e., running storage applications on switches) wasn't center stage at last month's Storage Networking World (SNW) conference, but it wasn't off-stage either—reflective perhaps of the generally high interest in the emerging technology among end users.
Aarohi is developing FabricStream "system-on-a-chip" ASICs for hosting applications in McDATA's switches and directors. The Aarohi chips are designed to host a variety of vendors' storage services or applications, including StoreAge's MultiView, MultiMirror, and MultiCopy.
However, McDATA has pushed back the ship date of its Sphereon Intelligent Switch platform from the end of this year to the first quarter of 2005. Company officials say the delay is due to the desire to ship the switches with 4Gbps (as opposed to 2Gbps) Fibre Channel connectivity, not with any inherent problems with the platform.
Though not spotlighted at SNW, fabric-based intelligent switches, running a limited number of applications, are also available from vendors such as Cisco and Maranti Networks (see "Maranti touts 'application-aware' controllers," InfoStor, January 2004, p. 8). While Cisco has been shipping IBM's TotalStorage Storage Volume Controller and Veritas' Volume Manager on switch blades for several months, the company has seen little traction, according to analysts.
Meanwhile, Brocade plans to ship its SilkWorm Fabric Application Platform with third-party applications later this year.
The company demonstrated the platform running storage services from vendors such as Alacritus, Incipient, and Kashya at SNW last fall and is expected to make a series of announcements in the next few months that will improve the flexibility of the architecture, according to sources.
As it stands, Brocade does not provide an upgrade path to fabric-based intelligence for its existing switch customers. Brocade users looking to move applications into switches will need to invest in a separate SilkWorm Fabric Application Platform. However, the company is expected to introduce blade technology that, among other things, will increase the flexibility that its customers have in implementing fabric-based intelligence.
Similarly, Maranti and MaXXan require an up-front investment in switching hardware to do fabric-based intelligence.
While Maranti claims its value-add is in the software and services it provides, MaXXan relies on third-party software vendors such as FalconStor to provide storage services for its switches.
In contrast, Cisco and McDATA do not require any investment in new switch platforms, just the purchase of specially designed blades or chips, respectively. "[In McDATA's case,] you can take an existing switch and add Aarohi chips," explains Joel Warford, vice president of marketing at Aarohi.
In addition to StoreAge, McDATA is working with EMC and other application vendors. While the company is initiating fabric-based intelligence in its Sphereon switches, it plans to extend support to its full line of switches and directors.
While most storage analysts and consultants agree that moving applications into the fabric makes sense for some applications, other consultants, such as Jacob Farmer, chief technology officer at Cambridge Computer, caution against moving intelligence into the network.
"I believe the role of the switch is to move data—not to mess with it," says Farmer, who argues that potential pitfalls of fabric-based intelligence include interoperability problems, vendor lock-in, and cost. (For his full argument, see "Being smart about 'intelligent' switches?", InfoStor, March 2004, p. 14.)
Nonetheless, Nancy Marrone-Hurley, a senior analyst at the Enterprise Storage Group, expects certain data-protection applications (e.g., mirroring, replication, and snapshots) as well as life-cycle management applications to migrate from hosts and disk arrays to switches and directors.
"Intelligence will be everywhere—in hosts, disk arrays, and in the fabric. The challenge will be in determining where it really belongs," she says.
In an InfoStor reader survey conducted last fall, 38% of respondents said they would prefer to run their storage applications on fabric switches/directors, while 41% said they preferred to do it at the disk-array level and 21% said they preferred to run applications on hosts.