topic Re: Does SAN not use TCP/IP protocol ? in General

Does SAN not use TCP/IP protocol ?

Shivkumar — Fri, 05 Jun 2009 01:46:34 GMT

Hi,

Does SAN not use TCP/IP protocol ?

Thanks,
Shiv

Re: Does SAN not use TCP/IP protocol ?

Torsten. — Fri, 05 Jun 2009 02:47:59 GMT

A SAN is using the fibre channel protocol and transports SCSI commands.

Re: Does SAN not use TCP/IP protocol ?

Uwe Zessin — Fri, 05 Jun 2009 03:39:26 GMT

And an iSCSI SAN transports SCSI commands over an IP infrastructure.

So, _some_ SANs use IP, but not all.

Re: Does SAN not use TCP/IP protocol ?

marsh_1 — Fri, 05 Jun 2009 09:49:36 GMT

hi,

if you go by the SNIA definitions a SAN is any storage accessed by means of a network. the term SAN historically tends to be associated with fibre channel protocol and fibre optic infrastructure, while NAS and iSCSI on the tcpip side have been seen as separate.
really you should refer to a SAN as a FIBRE CHANNEL SAN or an IP SAN, but increasingly SAN's will use both sets of technologies as they both have advantages that can complement each other. and given that the next few years should see more implementations of the fcoe inititiative coming into mainstream these previous distinctions will start to blur a lot more.

fwiw

Re: Does SAN not use TCP/IP protocol ?

Wickedsunny — Sat, 06 Jun 2009 06:21:35 GMT

SAN uses FC Protocol and they have a completely different layes of communication..

Fibre Channel is structured as a set of five hierarchical function levels. From lowest to highest, they are:

FC-0 â Physical level defines connectors, cables, and electrical characteristics of transition.

FC-1 â Encoding level defines the encoding/decoding and transmission protocol.

FC-2 â Signaling/framing protocol level determines how the data from the upper level is framed for handling by the transport level, and incorporates the management of frames, flow control, and cyclic redundancy check (CRC).

FC-3 â Common Services level is open for future implementation.

FC-4 â Protocol mapping level establishes the interface between Fibre Channel and the upper level protocols (usually provided by the vendorâ s device driver).

Read more here - http://searchstorage.techtarget.com/news/article/0,289142,sid5_gci1167265,00.html

Regards,S
Sunny

Re: Does SAN not use TCP/IP protocol ?

Sivakumar MJ._1 — Wed, 15 Jul 2009 11:04:43 GMT

Fibre Channel over IP (FCIP) is an Internet Protocol (IP)-based storage networking technology developed by the Internet Engineering Task Force (IETF).

FCIP mechanisms enable the transmission of Fibre Channel (FC) information by tunneling data between storage area network (SAN) facilities over IP networks.

FCIP Versus iSCSI

The other method, iSCSI, generates SCSI codes from user requests and encapsulates the data into IP packets for transmission over an Ethernet connection.

FCIP can only be used in conjunction with FC technology in comparison - iSCSI can run over existing Ethernet networks. SAN connectivity, through methods such as FCIP and iSCSI, offers benefits over the traditional point-to-point connections.

A hybrid technology called Internet Fibre Channel Protocol (iFCP) is an adaptation of FCIP that is used to move Fibre Channel data over IP networks using the iSCSI protocols.

Re: Does SAN not use TCP/IP protocol ?

Uwe Zessin — Wed, 15 Jul 2009 11:28:14 GMT

> ... (iFCP) is an adaptation of FCIP
> ... using the iSCSI protocols.

I don't know where you did cut&paste this from, but I don't beleive it uses iSCSI.
At least I could not find it in the RFC:

http://tools.ietf.org/html/rfc4172
"iFCP - A Protocol for Internet Fibre Channel Storage Networking"

And iFCP is not a tunnel technology

Re: Does SAN not use TCP/IP protocol ?

Shivkumar — Thu, 16 Jul 2009 03:37:18 GMT

Which is the best architecture if money is not constraint and our company is ready to go for expensive solution ?

Re: Does SAN not use TCP/IP protocol ?

Torsten. — Thu, 16 Jul 2009 04:10:06 GMT

XP24k :-)

Seriously speaking - it depends on your needs ...

Do you need to access the storage from servers only or also from clients? How many data, how many servers? ...

Re: Does SAN not use TCP/IP protocol ?

Sivakumar MJ._1 — Thu, 16 Jul 2009 05:58:07 GMT

All highend models from all vendors are Good..

The SAN Architecture what you design is purly based on your requirement.

Mostly core-edge topology is used.

Spend time in analysing your requirements (curent/future) in storage, servers, operations, management etc and proceed in choosing a solution.