Subject: iSCSI framing using TCP options

From: Ron Grinfeld <[email-masked]>
Date: Mon, 29 Oct 2001 09:11:29 +0200

iSCSI framing using TCP options was raised and noted in an unofficial
document (Jul/5/2000).
Was this issue ever concluded ? If so what is the resolution ?

__________________________________

	Best regards,
	Ron Grinfeld
	Siliquent Technologies Ltd.
 
      Yigal Alon 126 St.
      Tel Aviv,  Israel, 67443
      Tel. +972 3 6948671
      Fax. +972 3 6953736

---

From: Stephen Bailey <[email-masked]>
Date: Tue, 30 Oct 2001 09:46:49 -0500

Ron,

> iSCSI framing using TCP options was raised and noted in an
> unofficial document (Jul/5/2000).  Was this issue ever concluded ?
> If so what is the resolution ?

The TCP option approach was roundly rejected by the IETF transport
community.

The descendent of that effort, which takes the approach of delivering
framing information in-band (in the TCP stream) is still active.  The
authors of that draft are actively working on a new version in
response to many comments on draft-ietf-tsvwg-tcp-ulp-frame-00.txt.

One likely change in the next revision of the draft (which I'm sure
will go straight to last call, and win the hearts and minds of all who
read it :^), is that it will only define what is called PDU alignment
mode in -00.  The other primary client of TCP framing is RDMA, and
that community seems to have no interest in marker mode.  Therefore, I
would propose that iSCSI will continue with its own definition of
marker mode as it currently does, and additionally call out a
negotiation for ULP framing for TCP.  However, I don't think any
specific action is called for until draft-*-01.txt is released in the
next few weeks.

Steph