State-of-the-Art Storage
The storage arena is growing at a rapid speed, and with it an array of
exceptional storage solutions.
by Charles T. Clark
Network Magazine
01/05/01, 12:33 p.m. ET
With the advent of Storage Service Providers (SSPs),
these customers wanted to take advantage of SANs to
perform this operation electronically rather than
physically. One problem: The enabling Fibre Channel
technology didn't allow data to traverse the required
distances. Optical MANs helped solve this problem.
Another SSP problem that optical MANs help solve is
the SSPs' need for more space. SSPs initially
purchased space in the form of “pods” in colocation
facilities, such as those owned by Exodus. As their
business expanded, many SSPs found that the space
around them had been taken up. Optical
extenders-optical networking components such as
DWD multiplexers-provided an easy means of
accomplishing this expansion because they could go
over required distances to other locations where
facilities could be built out. The SSPs, in turn, were
able to provide their end-user customers with a “virtual
pod” to meet their storage requirements.
Three major vendors in this market are ONI Systems,
ADVA Optical Networking, and Nortel Networks. ONI
Systems is relatively new to the SAN space, but has
forged alliances with several companies, including
Brocade, EMC, and Compaq. ONI has deployed a
metro optical ring for an SSP called StorageNetworks
(see “Bridging the Gap”).
ADVA has been in the optical networking market since
1997, but is relatively new to the SAN extender space.
The company purchased SANs in February 2000 and
has allied itself with some major storage and
networking vendors. ADVA supplies EMC with optical
equipment for internal use and partners with it to solve
distance-extension problems for SANs. Working with
Verizon and INRANGE, ADVA has deployed a number of optical MANs.
Nortel is the market leader in both the DWDM long-haul and metro markets,
according to the Dell'Oro Group, an independent consultancy. Nortel works with
such partners as Brocade, Compaq, EMC, HDS, IBM, and QLogic. Nortel has
applied its experience in optical networking to the SAN extension problem with
its OPTera Metro 5200 Multiservice Platform. Initially, Nortel plans to focus on
the SSP market.
Industry analysts expect optical MANs to become more ubiquitous in the SAN
space, as more SSPs begin to supply storage services in metropolitan
areas-and as more corporations begin to modernize their backup/recovery and
disaster-recovery procedures over distances via SANs.
Storage Over IP
The Enterprise Storage Group's Duplessie contends that storage over IP is one
of the two most significant recent developments in the storage field (the other
being virtualization made possible by storage appliances). “The reason that
[storage over IP] is an important technology is that it's ultimately going to
enable users to have a choice between building storage networks on an
Ethernet infrastructure that they already have, or building a separate storage
network based on Fibre Channel,” says Duplessie. “Up until now there has been
no choice for users-they had to build a Fibre Channel- based storage network.”
Storage-over-IP systems offers a number of advantages: They protect more data
than was possible before, deploy more information anywhere, and leverage user
investments in existing IP network infrastructures. The major players in this
space are Cisco Systems (through its purchase of NuSpeed), SAN Valley,
Gadzoox, Nishon, SanCastle, Computer Networking Technology (CNT), Lucent
Technologies, Entrada, and Pirus. Cisco expects to introduce a storage-over-IP
product in January 2001, and Lucent expects to follow suit shortly thereafter.
Currently, however, CNT is the most active participant in storage over IP,
according to Duplessie.
CNT has a long history of working with IBM on ESCON channel extenders for
the S/390 and its predecessor mainframes, and this experience paid off when
the company was called upon to provide similar capabilities for SANs. Since
1997, CNT has evolved into working with large storage vendors and offering
solutions for remote disk mirroring, remote tape, and virtual tape. CNT has
worked with Compaq to provide Fibre Channel over ATM and has successfully
tested this solution over long distances.
CNT works with EchoStar Communications/DISH Network, a direct broadcast
satellite television company. Using a phased approach, EchoStar deployed a
SAN based on CNT's UltraNet Open Systems Director technology. In phase
one, the company began using the CNT SAN for server consolidation. In phase
two and three, EchoStar will perform remote disk mirroring and remote tape
vaulting over its existing IP infrastructure.
In phase one of the SAN deployment, EchoStar experienced a 500 percent
improvement in backup speed, according to Rick Nelson, senior IT architect at
EchoStar. Nelson used VERITAS' NetBackup in conjunction with the CNT
UltraNet SAN.
For its data replication over IP solution, CNT is working with EMC and Compaq.
EMC supplies the data replication software, which creates images of storage
data between storage systems by means of Symmetrix Remote Data Facility
(SRDF). SRDF contains the intelligence to implement data mirroring's
copy/recovery.
To deliver the SRDF over IP, CNT's UltraNet Storage Director software converts
SRDF data frames to IP packets. This results in data transport with increased
reliability and scalability. CNT has a similar relationship with Compaq, in which
it uses its UltraNet Storage Director with Compaq's Data Replication Manager
(DRM, the equivalent of SRDF) for remote mirroring. For remote
backup/recovery over IP, CNT is working with VERITAS' NetBackup product and
its own UltraNet Storage Director to provide remote backup/restore and
disaster-recovery solutions.
A Leading Role
With the many innovations brought about by storage networking (SAN and
NAS), the term “state-of-the-art” is becoming commonplace. And the result of
these innovations has been a true paradigm shift in the way storage is used.
Storage and its management no longer play a minor role in computing; rather,
in many cases, storage networking supplies solutions to many of today's most
pressing problems-how to accomplish backups in a 24-by-7 environment; how
to ensure 100 percent uptime; how to increase performance; and how to control
computing costs amid explosive growth.
So far, storage technology is keeping pace with the staggering growth in
computing. Based on the imaginative solutions that vendors have introduced so
far, there is every reason to believe that new solutions will continue to emerge
to meet the aforementioned needs for at least the next few years.
Charles T. Clark is a Haverhill, MA-based technology writer who focuses on
networking and storage networking issues. He can be reached at
cclark1038@email.msn.com.
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