OFA Logo Test Tutorial

For questions not answered here please e-mail ofalab@iol.unh.edu.


What are the membership options and benefits, and how do I join?

Please see our Membership Options page.

About OpenFabrics

What are OpenFabrics, OFA, and OFED?

The OpenFabrics Alliance (OFA) began in 2004 as an organization to standardize the InfiniBand transport protocol. In 2006 it expanded its mission to include the iWARP transport protocol as well. The OFED stack (OpenFabrics Enterprise Distribution) is an open-source Linux module that presents to application programmers a uniform, transport-independent interface to RDMA hardware of either type. In other words, a program written using the OFED stack will run without changes on both InfiniBand and iWARP network fabrics. Since 2005 the OFA has also been responsible for an equivalent stack in the Windows environment called WinOF.

What is RDMA?

RDMA stands for "remote direct memory access", which describes the mechanism whereby one computer is able to directly access another computer's memory. Such direct access is a "zero-copy" process, meaning that it bypasses conventional buffers and eliminates extraneous copying activity on both computers, significantly reducing processing overhead and communication delay (i.e., "latency"). As network links increase in capacity to ten gigabits per second and higher RDMA becomes attractive because it removes what would otherwise be overwhelming network processing load from a computer's central processor.

Related Technologies

What is EXS?

EXS stands for "extended sockets".

The Extended Sockets API (ES-API) is a specification published by the Open Group that defines extensions to the traditional socket API in order to provide asynchronous I/O and also memory registration for Remote Direct Memory Access (RDMA). These two major new features enable programmers to take advantage of today's multi-core processors and RDMA network hardware, such as InfiniBand, iWARP and RoCE interfaces, in a convenient yet efficient manner.

The UNH EXS interface is an OFED-based implementation of the ES-API that provides most of the features specified in the ES-API and a few additional features that give the programmer more flexibility. For example, the programmer can choose to program with synchronous rather than asynchronous I/O, and/or to program with or without memory registration. The programmer can also conveniently "tune" certain aspects of the EXS interface to take advantage of application requirements in order to provide better performance.

For more details see our EXS Overview (PDF).

To download the UNH EXS implementation please see our UNH EXS information and download page.


How can I access the OFA cluster remotely?

First you must acquire a username and password ("credentials") as well as encryption keys. Email us at ofalab@iol.unh.edu with a request for an account, and we will create one and send you your credentials. We will use the first part of your email address as your username and generate a password for you unless you request otherwise.

Please change your password once you are logged into a cluster system by issuing the passwd command.

To access to the cluster remotely you will need to use OpenVPN. An OpenVPN client configuration file will be provided with your credentials and keys. If you are using windows we highly recommend using OpenVPN GUI which can be found: http://openvpn.se/download.html

If using OpenVPN GUI, simply place the extracted zip file and the config file into openvpn gui's [installation dir]\config\[custom dir]; IE, C:\Program Files (x86)\OpenVPN\config\ofa, and start the app. Once started, there will be a new icon in your task bar that looks like two computer screens (will be red) next to a world. Right click on this icon, hover over the entry that matches your config file name; IE, ofa, and click on connect.

If you have any problems connecting, please contact our team at ofalab@iol.unh.edu.

What short URLs are available for printed brochures, etc?

for clickable email links for printed brochures
IOL's OpenFabrics page iol.unh.edu/ofa https://iol.unh.edu/ofa
OFILG Logo List iol.unh.edu/ofilglist https://iol.unh.edu/ofilglist
Logo Program iol.unh.edu/ofilp https://iol.unh.edu/ofilp
Test Plan iol.unh.edu/ofatestplan https://iol.unh.edu/ofatestplan