You want your secure fabrics to meet service level agreements (SLAs) that you and your customers have agreed to. Since the physical Interconnect is being subdivided into multiple secure fabrics, it is crucial that all secure fabrics can share the physical resources in a desirable manner. That is, you do not want some secure fabrics to consume Interconnect resources to the detriment of other secure fabrics. By default, secure fabric technology includes a round-robin priority scheme that helps prevent this.

However, based on the requirements and traffic associated with an application, or based on application workloads, you might want to adjust the priorities, and thus the performance, of some secure fabrics. Therefore, InfiniBand technology includes the concept of service levels. You assign secure fabrics one of the following Quality of Service levels (sometimes called “virtual lanes”), depending on the priority you want the secure fabric to have. From highest to lowest priority, the Quality of Service levels are as follows.

The IP- LAN secure fabric uses the default Interconnect partition value and is assigned a Quality of Service level equal to Bronze.

For each Quality of Service level, an algorithm provides a weighted priority value. “Weight” is a value that represents the number of 64-byte units to be processed before the software determines whether it is time to service another Quality of Service level. (The algorithm includes other factors besides weight.) The algorithm restricts how much data from that Quality of Service level (for example, Gold) will be processed before lower priority Quality of Service levels are processed (for example, Bronze). The algorithm ensures that processing of some low priority Quality of Service levels (for example, Bronze) can take place before processing of all Quality of Service levels of higher priority have been completed (for example, Platinum).

Note that Quality of Service levels are really only relevant on a fabric whose physical Interconnect is heavily utilized. By default, all secure fabrics will be provided fair and equal access to the Interconnect. In the unusual case that there is contention for a port to an enterprise partition platform (EPP), the Quality of Service for a secure fabric may be set to prioritize the traffic of that particular secure fabric through the port over the other secure fabrics that are also pushing traffic through that port. It is expected that this is an unusual and rare condition.