Direct network storage: A case for elimination of
computer based file servers and robust network storage expansion. By: James Sessions JES Hardware Solutions Phone (305) 597-3980 Internet: www.jessolutions.com Introduction Prior to 1980, minicomputers and mainframes dominated the
business computing scene. These machines were designed using the concept that application
and data be centralized, accessible to terminals with keyboards in decentralized locations
over various communication mediums, none of which could qualify as a "network"
by today's standards. Such design concepts were, understandably, limited by technology of
the time and affordability. Minicomputers and mainframes were expensive to own and
maintain, not to mention complex. In order to justify the cost of ownership, the ability
to amortize this enormous investment over a respectable number of users was mandatory.
However, the added investment of terminals, keyboards, multiplexers and off-site printers
became part of the total cost of ownership. The total investment was non-trivial but
nevertheless offered enough corporate infrastructure productivity enhancement to justify the expense.
That is, until microprocessors showed up in turn key microcomputers in early 1980
promising to change the landscape of small to mid-sized business computing forever. Over the course of the next several years, what became
known as the PC was finding its way onto corporate America's desktop by virtue of its
productivity to affordability ratio. The inability of these new micro-computers to share
data without the need for a minicomputer or mainframe became an issue to be reckoned with.
Hence, courtesy of several innovative companies, "Network Operating Systems",
or NOSes, began to appear either written for PC platforms or adapted to the PC as was
the case for Unix, inclusive all derivatives thereof. Within the context of "networking", emerging
terminology ensued to classify various equipment by form, fit and function. A PC running a
NOS was called a "server" because it served PC's running standalone OSes, called
"clients", with applications and/or data. (Please note the definition of both a
"server" and a "client" encompass hardware and software together).
Largely unnoticed was an interesting phenomenon not recognized as significant at the time.
This phenomenon became known as the decentralized application and data model (data and
application need no longer reside on the same computer as in former times). The Old Server Paradigm Acceptance of networking as a viable medium for
decentralized data and application processing in business has, over the past decade, given
rise to ever increasing server responsibilities. As responsibilities have escalated, so
too has the cost, complexity and manageability of servers. The result is a danger of
coming full circle, back to the confining centralized data and application approach of old
so diametrically opposed in today's distributed networks, Distributed networking liberated us from an era in which
centralized data and applications ran on mainframes and minicomputers that were expensive
to own and maintain. Advances in microprocessor and ASIC technology, coupled with
innovative interface topologies and standards initiatives, enabled systems manufacturers
to develop and deploy relatively inexpensive general purpose servers with more and more
horsepower over time. As a result, servers are capable of performing a myriad of tasks. In
the face of this, a pervasive trend toward client centric networking is ushering in a new
server paradigm (see figure1). In today's network environment, some database and E-mail
applications excepted, most users launch and run applications on their clients. As such,
severs are quickly becoming massive repositories of shared information, shifting away from
their traditional role of applications processing. Herein lies one of most significant
challenges facing the next generation of server engines and the microprocessors powering
them. Servers today are based on microprocessors designed for
application processing. Evidence attesting to this fact is the presence of additional
function specific processors in server sub-systems. Servers, PC based or otherwise, are
routinely built using add-in boards with embedded RISC processor engines controlling
functions such as Ethernet and/or SCSI interfaces. Even as these embedded engines find
their way down onto the motherboard, the principle reason for these inclusions is to
unload the application processor from tasks it was not principally designed to perform,
such as moving data. Up until now, manufacturing process technology had not advanced
sufficiently for a new paradigm to take hold thus forcing the only available alternative,
expanding upon the old paradigm by empowering the server with more and more
responsibility. By taking advantage of current technology, the possibility now exists to
embed most server functions into what JES engineers have defined as a "solution
set" (a combination of hardware and software coupled together to perform a particular
function or finite set of functions within highly integrated semiconductors). Issues Driving a New Server Paradigm
Enter the New Server Paradigm For the same reason the trend toward client-centric
networking has given rise to the NetPC initiative (a low cost, function specific, network
PC proposal) the trend toward lower cost, function specific servers has begun. The essence
of the new paradigm embodies the notion of extracting solution sets from the general
purpose server and moving them to a more optimized environment. This allows for the most
advantageous hardware and software architectures to be selected for processing these
services and then embedding all the resultant parts into a chip, or chip sets, or an
extensible small footprint printed circuit board. The level of integration depends chiefly
on available process technology in several areas of fabrication described later. Key to any intelligent embedded architecture is the
processor core selected. For example, the NetPC thin client reference platform calls for a
Pentium processor. Actually, any applications microprocessor could have been selected. In
this case, since Microsoft's products are to be used in conjunction with this particular
solution set, the Pentium was an obvious choice. Under the new server paradigm, the solution set will be
evaluated and may, or may not, use applications microprocessors. For example, moving data,
the principle function of a file server, optimally requires an input/output processor
tightly coupled with a realtime operating system, not an application processor with a
scaled down version of a general purpose operating system. JES Network Appliances In order to bring about this new server paradigm JES
Hardware Solutions has released a complete line of high speed network connected storage
solutions. The simplest being a network attached hard drive and the most complex being a
network connect RAID system. All systems will come with a Fast-Ethernet 10/100 RJ-45
interface. The SCSI interface will be ULTRA SCSI III running at 20MHZ and transferring at
40MB per second. Direct Connect Hard Drive (DC) The DC will be a four bay tower with the 10/100 network
interface built into the tower. The tower will contain one hard drive of sizes 1G,2G ,4G
,9G and 23G. We will use 10,000 RPM drives where applicable. Users can expand the drive in
the tower up to four. There will be a chainning connection to allow for the addition of
chained towers. The tower simply plugs into your existing network system.
The device can be managed using a common web browser. Supported clients are WFW 3.11 with
TCP/IP, Win95 and WinNT for SMB. UNIX workstations running NFS V2 and above. Direct Connect Mirror (DM) The DM will function the same as the Direct Connect Drive
(DC). The difference is that there will be a second disk drive used for mirroring data.
This is useful for when the primary drive fails and the mirror can take over until the
failed drive can be replaced. Once the failed drive is replaced the mirror can be copied
and again function as a mirror drive. The mirror software is build right into the direct
connect controller and performance is not affected for this reason. Direct Connect Tape/Jazz (DT) The DT will be a tape or Jazz drive that can be hooked up
to the computer network and can be used by all users to backup their data. This method is
much easier than trying to hook up a tape or Jazz directly to a computer be it a server or
workstation. All software will be contained on then device and backup is made simple. The
back up speed will be much faster since it will be hooked up to a SCSI interface. Direct Connect RAID (DR) The DR will be a very fast RAID system that you can connect
directly to your computer network . The system will be composed of a seven bay SCSI to
SCSI RAID with two network connections. These two network connections will allow for much
faster thruput on the network. The SCSI to SCSI RAID controller will control all of the
RAID features and all levels of RAID storage. The system will allow for additional drives
to be paced on the system without re-configuration. The drive system will be ULTRA SCSI
III FAST WIDE. The SCSI to SCSI RAID controller will have four drive channels and two host
channels (network connections). The four drive channels will reduce the number of drives
serviced by each channel, thus increasing system performance. All hard disk drives will be
hot swappable and hot spare option available. Each drive comes in its own separately
powered drive canister. The need for redundant power supplies is therefore eliminated. The
entire system will come pre-configured for level 5, however if you desire another level of
RAID the system can be re-configured for that level. Summary JES network appliances is poised to address todays
basic network needs such as performance without high cost, "plug and play"
simplicity, optimized design, self management with easy to understand options and no need
for complex network operating systems. This coupled with the leveraging of a mature
network topology makes the new network appliances a possible and best solution for network
storage, backup and other well defined solutions sets. As network appliances begin to enter the marketplace be
ready to see E-Mail servers, Internet Servers, Print Spoolers, file servers and hand held
network appliances. © 1997, 1998, 1999, JES Hardware Solutions and 
Figure 1
, Inc. Coconut Grove, Fla.
All Rights Reserved.