RDMA

This document specifies the format of Remote Direct Memory Access - Connection Manager (RDMA-CM) Private Data exchanged between RPC-over-RDMA version 1 peers as part of establishing a connection. The addition of the Private Data payload specified in this document is an optional extension that does not alter the RPC-over-RDMA version 1 protocol. This document updates RFC 8166.

This document specifies Upper-Layer Bindings of Network File System (NFS) protocol versions to RPC-over-RDMA version 1, thus enabling the use of Direct Data Placement. This document obsoletes RFC 5667.

This document specifies a protocol for conveying Remote Procedure Call (RPC) messages on physical transports capable of Remote Direct Memory Access (RDMA). This protocol is referred to as the RPC-over- RDMA version 1 protocol in this document. It requires no revision to application RPC protocols or the RPC protocol itself. This document obsoletes RFC 5666.

Minor versions of Network File System (NFS) version 4 newer than minor version 0 work best when Remote Procedure Call (RPC) transports can send RPC transactions in both directions on the same connection. This document describes how RPC transport endpoints capable of Remote Direct Memory Access (RDMA) convey RPCs in both directions on a single connection.

This document describes IBM's Shared Memory Communications over RDMA (SMC-R) protocol. This protocol provides Remote Direct Memory Access (RDMA) communications to TCP endpoints in a manner that is transparent to socket applications. It further provides for dynamic discovery of partner RDMA capabilities and dynamic setup of RDMA connections, as well as transparent high availability and load balancing when redundant RDMA network paths are available. It maintains many of the traditional TCP/IP qualities of service such as filtering that enterprise users demand, as well as TCP socket semantics such as urgent data.

This document specifies extensions to the IETF Remote Direct Memory Access Protocol (RDMAP) as specified in RFC 5040. RDMAP provides read and write services directly to applications and enables data to be transferred directly into Upper-Layer Protocol (ULP) Buffers without intermediate data copies. The extensions specified in this document provide the following capabilities and/or improvements: Atomic Operations and Immediate Data.

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. 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.

This document obsoletes RFC 5046.

The original RFCs that specified the Remote Direct Data Placement (RDDP) protocol suite did not create IANA registries for RDDP error codes, operation codes, and function codes. Extensions to the RDDP protocols now require these registries to be created. This memo creates the RDDP registries, populates them with values defined in the original RDDP RFCs, and provides guidance to IANA for future assignment of code points within these registries. [STANDARDS-TRACK]

This document updates RFC 5043 and RFC 5044 by extending Marker Protocol Data Unit (PDU) Aligned Framing (MPA) negotiation for Remote Direct Memory Access (RDMA) connection establishment. The first enhancement extends RFC 5044, enabling peer-to-peer connection establishment over MPA / Transmission Control Protocol (TCP). The second enhancement extends both RFC 5043 and RFC 5044, by providing an option for standardized exchange of RDMA-layer connection configuration. [STANDARDS-TRACK]

This document addresses enabling the use of Remote Direct Memory Access (RDMA) by the Network File System (NFS) protocols. NFS implementations historically incur significant overhead due to data copies on end-host systems, as well as other processing overhead. This document explores the potential benefits of RDMA to these implementations and evaluates the reasons why RDMA is especially well-suited to NFS and network file protocols in general. This memo provides information for the Internet community.

This document defines a Remote Direct Memory Access Protocol (RDMAP) that operates over the Direct Data Placement Protocol (DDP protocol). RDMAP provides read and write services directly to applications and enables data to be transferred directly into Upper Layer Protocol (ULP) Buffers without intermediate data copies. It also enables a kernel bypass implementation. [STANDARDS-TRACK]

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. [STANDARDS-TRACK]

This document analyzes security issues around implementation and use of the Direct Data Placement Protocol (DDP) and Remote Direct Memory Access Protocol (RDMAP). It first defines an architectural model for an RDMA Network Interface Card (RNIC), which can implement DDP or RDMAP and DDP. The document reviews various attacks against the resources defined in the architectural model and the countermeasures that can be used to protect the system. Attacks are grouped into those that can be mitigated by using secure communication channels across the network, attacks from Remote Peers, and attacks from Local Peers. Attack categories include spoofing, tampering, information disclosure, denial of service, and elevation of privilege. [STANDARDS-TRACK]

This document specifies an adaptation layer to provide a Lower Layer Protocol (LLP) service for Direct Data Placement (DDP) using the Stream Control Transmission Protocol (SCTP). [STANDARDS-TRACK]

Marker PDU Aligned Framing (MPA) is designed to work as an "adaptation layer" between TCP and the Direct Data Placement protocol (DDP) as described in RFC 5041. It preserves the reliable, in-order delivery of TCP, while adding the preservation of higher-level protocol record boundaries that DDP requires. MPA is fully compliant with applicable TCP RFCs and can be utilized with existing TCP implementations. MPA also supports integrated implementations that combine TCP, MPA and DDP to reduce buffering requirements in the implementation and improve performance at the system level. [STANDARDS-TRACK]

This document describes the applicability of Remote Direct Memory Access Protocol (RDMAP) and the Direct Data Placement Protocol (DDP). It compares and contrasts the different transport options over IP that DDP can use, provides guidance to ULP developers on choosing between available transports and/or how to be indifferent to the specific transport layer used, compares use of DDP with direct use of the supporting transports, and compares DDP over IP transports with non-IP transports that support RDMA functionality. This memo provides information for the Internet community.

This document defines an abstract architecture for Direct Data Placement (DDP) and Remote Direct Memory Access (RDMA) protocols to run on Internet Protocol-suite transports. This architecture does not necessarily reflect the proper way to implement such protocols, but is, rather, a descriptive tool for defining and understanding the protocols. DDP allows the efficient placement of data into buffers designated by Upper Layer Protocols (e.g., RDMA). RDMA provides the semantics to enable Remote Direct Memory Access between peers in a way consistent with application requirements. This memo provides information for the Internet community.

Overhead due to the movement of user data in the end-system network I/O processing path at high speeds is significant, and has limited the use of Internet protocols in interconnection networks, and the Internet itself -- especially where high bandwidth, low latency, and/or low overhead are required by the hosted application.

This document examines this overhead, and addresses an architectural, IP-based "copy avoidance" solution for its elimination, by enabling Remote Direct Memory Access (RDMA). This memo provides information for the Internet community.