DA: Datamover Architecture for the Internet Small Computer System Interface (iSCSI)
RFC 5047
| Document | Type |
RFC - Informational
(October 2007; No errata)
Updated by RFC 7146
|
|
|---|---|---|---|
| Last updated | 2015-10-14 | ||
| Stream | IETF | ||
| Formats | plain text pdf html bibtex | ||
| Stream | WG state | (None) | |
| Document shepherd | No shepherd assigned | ||
| IESG | IESG state | RFC 5047 (Informational) | |
| Consensus Boilerplate | Unknown | ||
| Telechat date | |||
| Responsible AD | Lars Eggert | ||
| Send notices to | (None) | ||
Network Working Group M. Chadalapaka
Request for Comments: 5047 HP
Category: Informational J. Hufferd
Brocade Inc.
J. Satran
IBM
H. Shah
Broadcom Corporation
October 2007
DA: Datamover Architecture for
the Internet Small Computer System Interface (iSCSI)
Status of This Memo
This memo provides information for the Internet community. It does
not specify an Internet standard of any kind. Distribution of this
memo is unlimited.
Abstract
The Internet Small Computer System Interface (iSCSI) is a SCSI
transport protocol that maps the SCSI family of application protocols
onto TCP/IP. Datamover Architecture for iSCSI (DA) defines an
abstract model in which the movement of data between iSCSI end nodes
is logically separated from the rest of the iSCSI protocol in order
to allow iSCSI to adapt to innovations available in new IP
transports. While DA defines the architectural functions required of
the class of Datamover protocols, it does not define any specific
Datamover protocols. Each such Datamover protocol, defined in a
separate document, provides a reliable transport for all iSCSI PDUs,
but actually moves the data required for certain iSCSI PDUs without
involving the remote iSCSI layer itself. This document begins with
an introduction of a few new abstractions, defines a layered
architecture for iSCSI and Datamover protocols, and then models the
interactions within an iSCSI end node between the iSCSI layer and the
Datamover layer that happen in order to transparently perform remote
data movement within an IP fabric. It is intended that this
definition will help map iSCSI to generic Remote Direct Memory Access
(RDMA)-capable IP fabrics in the future comprising TCP, the Stream
Control Transmission Protocol (SCTP), and possibly other underlying
network transport layers, such as InfiniBand.
Chadalapaka, et al. Informational [Page 1]
RFC 5047 DA October 2007
Table of Contents
1. Motivation ......................................................4
1.1. Intent .....................................................4
1.2. Interpretation of Requirements .............................5
2. Definitions and Acronyms ........................................5
2.1. Definitions ................................................5
2.2. Acronyms ...................................................6
3. Architectural Layering of iSCSI and Datamover Layers ............7
4. Design Overview .................................................9
5. Architectural Concepts .........................................10
5.1. iSCSI PDU Types ...........................................10
5.1.1. iSCSI Data-Type PDUs ...............................10
5.1.2. iSCSI Control-Type PDUs ............................11
5.2. Data_Descriptor ...........................................11
5.3. Connection_Handle .........................................11
5.4. Operational Primitive .....................................12
5.5. Transport Connection ......................................13
6. Datamover Layer and Datamover Protocol .........................13
7. Functional Overview ............................................14
7.1. Startup ...................................................14
7.2. Full Feature Phase ........................................15
7.3. Wrap-up ...................................................15
8. Operational Primitives Provided by the Datamover Layer .........16
8.1. Send_Control ..............................................16
8.2. Put_Data ..................................................17
8.3. Get_Data ..................................................17
8.4. Allocate_Connection_Resources .............................18
8.5. Deallocate_Connection_Resources ...........................19
8.6. Enable_Datamover ..........................................19
8.7. Connection_Terminate ......................................20
8.8. Notice_Key_Values .........................................20
8.9. Deallocate_Task_Resources .................................20
9. Operational Primitives Provided by the iSCSI Layer .............21
Show full document text