IP based SAN Technologies:

On request by few of my blog readers, i will be posting iSCSI specific information in my upcoming posts.

Storage Neworking technologies from past few decades was dominated by the high speed serial Fibre channel [FC] & SCSI [Small Computer System Interface], the implementation use to be for limited enterprises because of high cost of implementation.
over the period of time, Technology evolved & more enterprise inter-network demands resulted in rapid innovations for implementing the storage networks to work on traditional & highly conventional TCP/IP protocol technology.
As a initial innovation result FCIP & iFCP were implemented. the TCP/IP protocol is used as Gateway protocol on Gateway devices that inter connect the two or more FC SAN sub-networks.

FCIP: Fibre Channel over TCP/IP
* A TCP/IP based tunneling protocol for connecting geographically distributed Fibre Channel SANs transparently to both FC and IP.
* Provides a mechanism to tunnel Fibre Channel over IP based networks
* Leverage IP infrastructure to interconnect and extend FC SAN.
* FCIP Gateways enable to connect to a standard Gigabit Ethernet/IP network.
* Cost effective
* The FCIP gateway can be a separate device, or its functionality can be integrated into the Fibre Channel switch.
* Can be deployed over LANs, MANs and WANs

iFCP: Internet Fibre Channel Protocol
* iFCP is TCP/IP based Session protocol for connecting two or more FC SANs, two devices from two different FC SANs.
* Fibre Channel devices (e.g., switches, disk arrays, and HBAs) connect to an iFCP gateway or switch. Each Fibre Channel session is terminated at the local gateway and converted to a TCP/IP session via iFCP.
A second gateway or switch receives the iFCP session and initiates a Fibre Channel session.
* Sessions include device-to-device, device-to-SAN, and SAN-to-SAN communications.

Pictures attached with this post will give you brief idea about FCIP, iFCP & iSCSI.

The latest & hottest TCP/IP implementation is iSCSI protocol & the entire SAN can be designed on Ethernet or TCP/IP technology using iSCSI Protocol structure.
i will be posting detailed information about iSCSI technology in the upcoming posts, watch out this space.....

SAN Introduction

* SAN is the network between Storage devices & Host/servers, designed & implemented to provide pool of Storage resources mainly to fulfill the exponential need of storage backbone for small & medium offices, Mid-range & large Enterprises Using Fibre Channel or iSCSI Technologies.
* SAN provides block-orient I/O between the Server systems and the target storage systems, in comparison of NAS that gives File-oriented I/O.
* In comparison to DAS & NAS, SAN provides High availability of storage resources, more Secure & Reliable, Cost effective, reduced Downtime, secured Backup storage solutions.
* SAN is designed & implimented using either robust Fibre Channel Technology (FC SAN) or evergreen Internet Protocol Technology (iSCSI SAN). might be using both in near future.
* The SAN is often built on a dedicated network fabric that is separated from the LAN network to ensure the latency-sensitive block I/O SAN traffic does not interfere with the traffic on the LAN network.
* Even when iSCSI SAN runs over Ethernet technology, the SAN may still be separated from the LAN either physically, or logically via VLAN to ensure the security and the QoS on the SAN traffic.
* SAN storage devices are specifically designed as stand alone devices that can communicate with the Servers or hosts of different server vendors, Operating system vendors, Host adapter vendors, Switch vendors.
* SAN Architecture, accommodates DAS Implemented setups within its infrastructure & hence, DAS & SAN setups will co-exist in the same SAN infrastructure & also allows Enterprises to migrate from existing DAS setups to newer SAN setups & implementations.
* SAN Islands, implemented in different geographical locations can communicate using gateway devices such as FCIP based gateway, iFCP based gateway & iSCSI based gateway.