The Sockets Direct Protocol (SDP) is a transport-agnostic protocol to support stream sockets over remote direct memory access (RDMA)

network fabric Switched fabric or switching fabric is a network topology in which network nodes interconnect via one or more network switches (particularly crossbar switches). Because a switched fabric network spreads network traffic across multiple physical ...

s. SDP was originally defined by the Software Working Group (SWG) of the

InfiniBand Trade Association InfiniBand (IB) is a computer networking communications standard used in high-performance computing that features very high throughput and very low latency. It is used for data interconnect both among and within computers. InfiniBand is also used ...

. Originally designed for

InfiniBand InfiniBand (IB) is a computer networking communications standard used in high-performance computing that features very high throughput and very low latency. It is used for data interconnect both among and within computers. InfiniBand is also used ...

(IB), SDP is currently maintained by the

OpenFabrics Alliance The OpenFabrics Alliance is a non-profit organization that promotes remote direct memory access (RDMA) switched fabric technologies for server and storage connectivity. These high-speed data-transport technologies are used in high-performance ...

Protocol

SDP defines a standard wire protocol over an RDMA fabric to support stream sockets (SOCK_STREAM). SDP uses various RDMA network features for high-performance

zero-copy "Zero-copy" describes computer operations in which the CPU does not perform the task of copying data from one memory area to another or in which unnecessary data copies are avoided. This is frequently used to save CPU cycles and memory bandwid ...

data transfers. SDP is a pure wire-protocol level specification and does not go into any socket API or implementation specifics. The purpose of the Sockets Direct Protocol is to provide an RDMA-accelerated alternative to the TCP protocol on IP. The goal is to do this in a manner which is transparent to the application.

Solaris 10 Solaris is a proprietary software, proprietary Unix operating system originally developed by Sun Microsystems. After the Acquisition of Sun Microsystems by Oracle Corporation, Sun acquisition by Oracle in 2010, it was renamed Oracle Solaris. So ...

and

Solaris 11 Solaris may refer to: Arts and entertainment Literature, television and film * ''Solaris'' (novel), a 1961 science fiction novel by Stanisław Lem ** ''Solaris'' (1968 film), directed by Boris Nirenburg ** ''Solaris'' (1972 film), directed by ...

Express include support for SDP. Several other Unix operating system variants plan to include support for Sockets Direct Protocol. Windows offers a subsystem called Winsock Direct, which could be used to support SDP. SDP support was introduced to the JDK 7 release of the Java Platform, Standard Edition (July 2011) for applications deployed in on Solaris and

Linux Linux ( or ) is a family of open-source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically packaged as a Linux distribution, which ...

operating systems (OFED 1.4.2 and 1.5). Oracle Database 11g supports connection over SDP. Sockets Direct Protocol only deals with stream sockets, and if installed in a system, bypasses the OS resident TCP stack for stream connections between any endpoints on the RDMA fabric. All other socket types (such as datagram, raw, packet, etc.) are supported by the Linux IP stack and operate over standard IP interfaces (i.e., IPoIB on InfiniBand fabrics). The IP stack has no dependency on the SDP stack; however, the SDP stack depends on IP drivers for local IP assignments and for IP address resolution for endpoint identifications. SDP is used by the Australian telecommunications company

Telstra Telstra Group Limited is an Australian telecommunications company that builds and operates telecommunications networks and markets voice, mobile, internet access, pay television and other products and services. It is a member of the S&P/ASX 20 ...

on their 3G platform

Next G Telstra Group Limited is an Australian telecommunications company that builds and operates telecommunications networks and markets voice, mobile, internet access, pay television and other products and services. It is a member of the S&P/ASX 20 ...

to deliver streaming mobile TV. This protocol has been deprecatedTziporet Koren, "[ewg] Status of SDP? (and ib_sdp patch for Linux-3.4.x)" Apr 14 2012
"Is SDP obsolete? - its deprecated" or not maintained by

OFED The OpenFabrics Alliance is a non-profit organization that promotes remote direct memory access (RDMA) switched fabric technologies for server and storage connectivity. These high-speed data-transport technologies are used in high-performance ...

in the latest releases, hence look for alternatives. The probable suggestions will be

RSocket RSocket is an application protocol initially developed bNetflix that supports Reactive Streams. The motivation behind its development was to replace hypertext transfer protocol (HTTP), which is inefficient for many tasks such as microservices co ...

Winsock In computing, the Windows Sockets API (WSA), later shortened to Winsock, is an application programming interface (API) that defines how Windows network application software should access network services, especially TCP/IP. It defines a standar ...

, etc.

References

{{Reflist, 30em Network protocols