Direct Data Placement over Reliable Transports
RFC 5041
Document | Type |
RFC - Proposed Standard
(October 2007; No errata)
Updated by RFC 7146
Was draft-ietf-rddp-ddp (rddp WG)
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Authors | Paul Culley , Hemal Shah , Jim Pinkerton , Renato Recio | ||
Last updated | 2015-10-14 | ||
Stream | IETF | ||
Formats | plain text html pdf htmlized bibtex | ||
Reviews | |||
Stream | WG state | (None) | |
Document shepherd | No shepherd assigned | ||
IESG | IESG state | RFC 5041 (Proposed Standard) | |
Consensus Boilerplate | Unknown | ||
Telechat date | |||
Responsible AD | Lars Eggert | ||
Send notices to | jeff.hilland@hp.com, dave.garcia@hp.com, bmt@zurich.ibm.com |
Network Working Group H. Shah Request for Comments: 5041 Broadcom Corporation Category: Standards Track J. Pinkerton Microsoft Corporation R. Recio IBM Corporation P. Culley Hewlett-Packard Company October 2007 Direct Data Placement over Reliable Transports 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 The Direct Data Placement protocol provides information to Place the incoming data directly into an upper layer protocol's receive buffer without intermediate buffers. This removes excess CPU and memory utilization associated with transferring data through the intermediate buffers. Table of Contents 1. Introduction ....................................................3 1.1. Architectural Goals ........................................3 1.2. Protocol Overview ..........................................4 1.3. DDP Layering ...............................................6 2. Glossary ........................................................7 2.1. General ....................................................7 2.2. LLP ........................................................9 2.3. Direct Data Placement (DDP) ................................9 3. Reliable Delivery LLP Requirements .............................12 4. Header Format ..................................................13 4.1. DDP Control Field .........................................13 4.2. DDP Tagged Buffer Model Header ............................14 4.3. DDP Untagged Buffer Model Header ..........................16 4.4. DDP Segment Format ........................................17 5. Data Transfer ..................................................18 5.1. DDP Tagged or Untagged Buffer Models ......................18 5.1.1. Tagged Buffer Model ................................18 Shah, et al. Standards Track [Page 1] RFC 5041 DDP Protocol Specification October 2007 5.1.2. Untagged Buffer Model ..............................18 5.2. Segmentation and Reassembly of a DDP Message ..............19 5.3. Ordering Among DDP Messages ...............................21 5.4. DDP Message Completion and Delivery .......................21 6. DDP Stream Setup and Teardown ..................................22 6.1. DDP Stream Setup ..........................................22 6.2. DDP Stream Teardown .......................................22 6.2.1. DDP Graceful Teardown ..............................22 6.2.2. DDP Abortive Teardown ..............................23 7. Error Semantics ................................................24 7.1. Errors Detected at the Data Sink ..........................24 7.2. DDP Error Numbers .........................................25 8. Security Considerations ........................................26 8.1. Protocol-Specific Security Considerations .................26 8.2. Association of an STag and a DDP Stream ...................26 8.3. Security Requirements .....................................27 8.3.1. RNIC Requirements ..................................28 8.3.2. Privileged Resources Manager Requirement ...........29 8.4. Security Services for DDP .................................30 8.4.1. Available Security Services ........................30 8.4.2. Requirements for IPsec Services for DDP ............30 9. IANA Considerations ............................................31 10. References ....................................................32 10.1. Normative References .....................................32 10.2. Informative References ...................................33 Appendix A. Receive Window Sizing ................................34 Appendix B. Contributors .........................................34 Table of Figures Figure 1: DDP Layering ............................................6 Figure 2: MPA, DDP, and RDMAP Header Alignment ....................7 Figure 3: DDP Control Field ......................................13Show full document text