Network Working Group M. Ko
Request for Comments: 5046 IBM Corporation
Category: Standards Track M. Chadalapaka
Hewlett-Packard Company
J. Hufferd
Brocade, Inc.
U. Elzur
H. Shah
P. Thaler
Broadcom Corporation
October 2007
Internet Small Computer System Interface (iSCSI) Extensions
for Remote Direct Memory Access (RDMA)
Status of This Memo
This document specifies an Internet standards track protocol for the
Internet community, and requests discussion and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
Abstract
Internet Small Computer System Interface (iSCSI) Extensions for
Remote Direct Memory Access (RDMA) provides the RDMA data transfer
capability to iSCSI by layering iSCSI on top of an RDMA-Capable
Protocol, such as the iWARP protocol suite. An RDMA-Capable Protocol
provides RDMA Read and Write services, which enable data to be
transferred directly into SCSI I/O Buffers without intermediate data
copies. This document describes the extensions to the iSCSI protocol
to support RDMA services as provided by an RDMA-Capable Protocol,
such as the iWARP protocol suite.
Ko, et al. Standards Track [Page 1]RFC 5046 iSER Specification October 2007Table of Contents
1. Introduction ....................................................5
1.1. Motivation .................................................5
1.2. Architectural Goals ........................................6
1.3. Protocol Overview ..........................................7
1.4. RDMA Services and iSER .....................................8
1.4.1. STag ................................................8
1.4.2. Send ................................................9
1.4.3. RDMA Write ..........................................9
1.4.4. RDMA Read ...........................................9
1.5. SCSI Read Overview ........................................10
1.6. SCSI Write Overview .......................................10
1.7. iSCSI/iSER Layering .......................................10
2. Definitions and Acronyms .......................................11
2.1. Definitions ...............................................11
2.2. Acronyms ..................................................17
2.3. Conventions ...............................................19
3. Upper Layer Interface Requirements .............................19
3.1. Operational Primitives Offered by iSER ....................20
3.1.1. Send_Control .......................................20
3.1.2. Put_Data ...........................................20
3.1.3. Get_Data ...........................................21
3.1.4. Allocate_Connection_Resources ......................21
3.1.5. Deallocate_Connection_Resources ....................22
3.1.6. Enable_Datamover ...................................22
3.1.7. Connection_Terminate ...............................22
3.1.8. Notice_Key_Values ..................................23
3.1.9. Deallocate_Task_Resources ..........................23
3.2. Operational Primitives Used by iSER .......................23
3.2.1. Control_Notify .....................................24
3.2.2. Data_Completion_Notify .............................24
3.2.3. Data_ACK_Notify ....................................24
3.2.4. Connection_Terminate_Notify ........................25
3.3. iSCSI Protocol Usage Requirements .........................25
4. Lower Layer Interface Requirements .............................26
4.1. Interactions with the RCaP Layer ..........................26
4.2. Interactions with the Transport Layer .....................27
5. Connection Setup and Termination ...............................27
5.1. iSCSI/iSER Connection Setup ...............................27
5.1.1. Initiator Behavior .................................29
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