The Sockets Direct Protocol (SDP) is a transport-agnostic protocol to support stream sockets over

remote direct memory access In computing, remote direct memory access (RDMA) is a direct memory access from the memory of one computer into that of another without involving either one's operating system. This permits high-throughput, low- latency networking, which is especia ...

(RDMA) network fabrics. SDP was originally defined by the Software Working Group (SWG) of the InfiniBand Trade Association. 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 c ...

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 In computer science, zero-copy refers to techniques that enable data transfer between memory spaces without requiring the CPU to copy the data. By avoiding redundant copying, zero-copy methods minimize CPU usage and memory bandwidth, leading ...

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 Oracle Solaris is a proprietary Unix operating system offered by Oracle for SPARC and x86-64 based workstations and servers. Originally developed by Sun Microsystems as Solaris, it superseded the company's earlier SunOS in 1993 and became kno ...

and

Solaris 11 Solaris is the Latin word for sun. It 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 ** ''Sol ...

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 ( ) is a family of open source Unix-like operating systems based on the Linux kernel, an kernel (operating system), operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically package manager, pac ...

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 related products and services. It is a member of the S&P/ASX 20 stock index, and is Australia's largest telecomm ...

on their 3G platform

Next G Telstra Group Limited is an Australian telecommunications company that builds and operates telecommunications networks and markets related products and services. It is a member of the S&P/ASX 20 stock index, and is Australia's largest telecom ...

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

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