Download that compliments the - Strategic

Knowing when to deploy
DAS NAS and SAN can optimize
Availability
Scalability
Performance
Manageability
Cost effectiveness
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DAS, NAS, FC-SAN, E-SAN
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Coexistent architectures
DAS-Based on weak storage industry standards
NAS-Based on strong network industry standards
FC-SAN-SNIA standards will not happen this year
E-SAN - No standards yet and unsolved problems
Appropriate Applications for each
Four Choices in NAS
Location of the Network
Determines the Architecture
OSI Communication layers
Network Protocols
Frames contain ‘nested’ packets
IP Packets can contain block
requests or NFS/CIFS file requests
DAS = Direct Attached Storage
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Evolved from the Storage Industry
95% of all storage sold today
7 Major variations of SCSI
Many implementations of FC
Host file systems request blocks of
data with SCSI or FC commands
Data is returned over SCSI buses or
FC loops
DAS Topology
A Performance Critical
Customer Reservation System
NAS = Network Attached Storage
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Based on strong remote file system
standards like NFS and CIFS
Uses strong network standards for file
requests and data
Pioneered by Auspex
Predicted by IDC to grow from $1.7 B to
$6.6B in three years or 67% per year.
Outboard File System can be Fat or Thin
Networks offer security and congestion
control unlike FC-SAN
Necessary for NFS/CIFS file sharing
NAS Topology
NAS NFS and CIFS Sharing
A UNIX-based document control database
accessed by NT clients in purchasing
Distributed Storage before
NAS Consolidation
Distributed Storage after NAS
Consolidation
Technical NAS Applications
MCAD, ECAD, software development or
geoseismic applications
Internet Applications
Optimized for DAS and NAS
FC-SAN = Fibre Channel SAN
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SAN means FC-SAN to most folks
“Hot” topic - yet misunderstood
7%-10% of shops in production
Vision is heterogeneous
Reality is homogeneous [proprietary]
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EMC = ESN, Compaq=ENSA, HDS=FDN
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Security Risks without standards
 Bottlenecks without standards
 Heterogeneous switch interoperability
is the main problem today
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Heterogeneous FC-SAN Vision
Homogeneous FC-SAN Reality
FC-SAN Link and Node Congestion
Deterrents to FC-SAN today
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Source: Computerworld August 7, 2000 - Based on a recent
survey of 100 IT professionals aware of FC-SAN first hand.
E-SAN = Ethernet SAN
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Where block requests are sent over IP
iSCSI proposed by CISCO/IBM to IETP
3ware’s Storage Control Protocol (SCP)
over TCP uses non-SCSI commands
SCSI over UDP (SoIP) proposed by
Nishan
Adaptec is proposing a new transport
layer especially designed for SCSI
transport over IP
FC switch vendors fight back by
encapsulating FC commands over IP
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Cisco and Brocade plan to encapsulate
FC over TCP/IP
FCIP is being proposed by Gadzoox and
Lucent for long distance WAN / MAN /
SAN implementations.
This may lead to FC-SANs
interconnected in long distance E-SANs
Why the Fibre Channel people
are worried
Summary
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The location of the network determines
the architecture
DAS, FC-SAN, E-SAN = blocks / data
NAS = file requests / data
Coexistent architectures
Only NAS is based on strong network
industry & remote file system standards
Only proprietary FC-SANs control the
security risks and bottlenecks of FC
E-SAN is emerging with performance
and standards problems to be solved