The Access Layer is the low level operating system infrastructure (plumbing) used for accessing the InfiniBand™  fabric. It includes all basic transport services needed to support upper level InfiniBand protocols, middleware, and management agents. The Access Layer is intended to provide the services described in Chapter 10, 11, and 12 of the InfiniBand  Architecture Specification Vol 1a for the Linux Operating System. It also provides the low level common framework that supports development of the Management Services described in Chapter 13, 14, 15, and 16 of the InfiniBand Architecture Specification, Vol 1a. 

High Level Architecture

Refer to the Access Layer Software Architecture Specification white paper in the documents section for more details.

Project Definition

The Access Layer project defines both the User-mode InfiniBand Access Interface and Kernel-Mode InfiniBand  Access Layer interface, as shown in the architecture diagram above. The project is developing a complete open source implementation of the kernel and user mode access layers. The design is intended to support all Host Channel Adapter (HCA) vendor's products.  The HCA driver interface, as shown above,  is being defined in the HCA Device Driver Kit (DDK) project, located under Hardware Drivers. The HCA DDK also contains a sample driver template and headers needed to develop a driver that plugs into the access layer infrastructure.


The major goals of the project 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 are: 


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: 05/02/2002 01:47 PM