The Multiple Bus Architecture (MBA) allows the user to provide power or instrumentation to any circuit connected to the system without special interface cables. The 1,000-point switching module contains the standard two system buses and two additional Random Access Switching System (RASS) buses, which can be connected to the required power or instrumentation. The system provides up to ten random access buses.
This is an MBA 100-point switching card used in 2500 systems.
This is the MBA switching card's matching RASS card.
Source: NETS User Manual, Revision D, document 132-06035-0006, section 10.3.4.