INTRODUCTION OF STORAGE AREA NETWORK

SUMMARY

1)What is SAN

2)Basics of SAN

3)Architecture of SAN

4)Basic mechanism of SAN

WHAT IS SAN

Storage area network is a design to transfer data,

from server to clients. It is alternative to the directly

attached targets. It is primarily used as the storage

device server can access this. It is also highly

performance storage device enabling to communicate

with one another.

TECHNOLOGIES

Different of technologies are used for SAN. Most popular

is the Fiber channel. But IP based solutions are also used.

Concepts of SAN also implemented on the devices those are

attached to like disk, tapes, RAID, file server etc. We

frequently used NAS and SAN collaterally. Difference

between them are SAN is network storage sub system NAS

is storage subsystem. SAN extension of disk channel not

connected to server but NAS connected to server via IP

network.

BASICS OF SAN

Different technologies can be used to

interconnect different network nodes. Fiber

channel is dedicated high performance channel.

It is used fiber channel protocol. SCSI protocol

carry IP packet over the network. SCSI is the

extension of the SCSI bus.

INITIATOR AND TARGET

Fiber channel can be source or the destination

of the information. If the node is initiator then

it is connected to the network through HBA

(Host Bus Adapter) it is a physical layer

connection. It may be electrical or fiber optical.

If the node is target then it is connected

through RAID (Redundant Array of Independent

Disk) or storage drives.

HARD DRIVES

Basic storage is the hard drives. It is

composed of different disks, platters, cylinders,

track and sectors. It is metallic disk used for

storage of data. Logical block address within

the disk is 512 byte. Files can be stored in the

sectors so they can be stored and retrieved. File

system deals with clusters of blocks and it uses

FAT (File Allocation Table) to map the file

sectors.

JBOD AND RAID

Jbods are group of disks packaged in a

connected via FC loop. RAID is more

sophisticated device it improves the storage

disk performance. It improves the

performance the reading and writing from

disk at the same time or it mirroring the

information on the multiple disk array.

ARCHITECTURE OF SAN

RAID array containing the disk array and RAID

controller . It providing hardware and feature of

RAID 0- 5. Direct attached storage is an architecture

is used to storage privately attached servers. It is

expensive and complex to manage. Storage is

accessed from block level not file level. It is high

performance. It uses good management tool and

storage is shared. It uses interoperability.

NAS

Network attached storage is an architecture

which attached to the server with a

multiprocess network. This network is a IP

process network. Transmission Control Protocol

can be tuned to optimized storage transport.

MECHANISM OF SAN

Fiber channel act as a transport layer of SCSI.

Fiber channel is used instead of TCP/IP network

to connect server to the storage. In the long

graphical distance IP can be used. It can be

used in the IP traffic. FC offers layer 2 transport

service and used layer 3 to map upper layer

protocols like SCSI, HIPPI and IP.

SWITCHING FABRIC SERVICE

FC switching fabric relies upon number of software

applications and to deliver transport service.

Most relevant ones are Zoning, Alias service, domain

controller.

Those service allow fabric to function without

disruption.

It consist of a set of information distributed across

the fabric nodes.

STANDARDIZATION BODY

Fiber channel standardized by ANSI T11

committee.

SCSI standardized by T10 committee. URL =

www.T10.org

FCIA is the fiber channel industry association

it is not involved in the standardization process.

University of New Hampshire also involved

here.

THANK YOU