The implementation of uDAPL over InfiniBand™ (IB) provides a standardized user mode API over IB fabrics as defined by the DAT Collaborative.  Implemented as a standard Linux shared object, it interfaces to the IB Access Layer.  uDAPL gains access to the HCA and subnet management services through this Access Layer.  All uDAPL data transfers use the reliable connection service.

The primary responsibilities of the uDAPL library include: performing name to address translations, establishing connections and transferring the data reliably.

High Level Architecture

The uDAPL components reside in user mode above the Access Layer interface, as depicted in the following diagram.  Refer to the uDAPL High Level Design (HLD) document for more details.

Copyright © 2002 Intel Corp.

Project Definition

uDAPL is a System Area Network (SAN) provider that enables an application to bypass the standard TCP/IP provider and use the native transport to communicate between hosts in a cluster of servers and workstations on the fabric.  This also enables the applications to take advantage of the underlying transport service provided by InfiniBand to permit direct I/O between the user mode processes. 

The primary responsibility of uDAPL are transport independent connection management, transport independent low latency data transfer and completion.


The detailed goals for uDAPL are available at the DAT Collaborative.  In summary, the key requirements are:

Licensing Details

This software is being made available under a choice of one of two licenses. You may choose to be licensed under either the GNU General Public License (GPL) Version 2, June 1991, available at http://www.fsf.org/copyleft/gpl.html, or the Intel BSD + Patent License, further described here.


The deliverables of this project include:


Actual sub-project timelines are not yet determined and will be formulated by the participants of the sub-project.

How to Get Involved

The best way to contribute to this effort is to get in touch with the contact for the area you are interested in.  New participants are welcomed and encouraged to join in this effort to bring InfiniBand support to the Linux operating system.

Project News

The project news is included on the SourceForge site.  Click the "News" link at the left under "SourceForge Services".

Last Updated: 08/14/2002 04:27 PM