Lesson: Understanding the Sockets Direct Protocol

For high performance computing environments, the capacity to move data across a network quickly and efficiently is a requirement. Such networks are typically described as requiring high throughput and low latency. High throughput refers to an environment that can deliver a large amount of processing capacity over a long period of time. Low latency refers to the minimal delay between processing input and providing output, such as you would expect in a real-time application.

In these environments, conventional networking using socket streams can create bottlenecks when it comes to moving data. Introduced in 1999 by the InfiniBand Trade Association, InfiniBand (IB) was created to address the need for high performance computing. One of the most important features of IB is Remote Direct Memory Access (RDMA). RDMA enables moving data directly from the memory of one computer to another computer, bypassing the operating system of both computers and resulting in significant performance gains.

The Sockets Direct Protocol (SDP) is a networking protocol developed to support stream connections over InfiniBand fabric. SDP support was introduced to the JDK 7 release of the Java Platform, Standard Edition ("Java SE Platform") for applications deployed in the Solaris Operating System ("Solaris OS") and on Linux operating systems. The Solaris OS has supported SDP and InfiniBand since Solaris 10 5/08. On Linux, the InfiniBand package is called OFED (OpenFabrics Enterprise Distribution). The JDK 7 release supports the 1.4.2 and 1.5 versions of OFED.