The main computer system of the Vanguard is probably the most important single operational element of the starship next to the crew. The computer is directly analogous to the autonomic nervous system of a living being, and is responsible in some way for the operation of virtually every other system of the vehicle.
Crew interface for the main computer is provided by the Library Computer Access and Retrieval System software, usually abbreviated as LCARS. LCARS provides both keyboard and verbal interface ability, incorporating highly sophisticated artificial intelligence routines and graphic display organization for maximum crew ease-of-use.
The heart of the main computer system is a set of two redundant main processing cores. Any of these three cores is able to handle the primary operational computing load of the entire vessel. Two redundant cores are located near the center of the Primary Hull between Decks 6 & 10 and between Decks 7 & 11, while a third remains unattached and in storage.
Each main core incorporates a series of miniature subspace field generators, which creates a symmetrical (nonpropulsive) field distortion of 3350 millicochranes within the faster-than-light (FTL) core elements. This permits the transmission and processing of optical data within the core at rates significantly exceeding lightspeed.
The two main cores in the Primary Hull run in parallel clock-sync with each other, providing 100% redundancy. In the event of any failure in either core, the other core is able to instantly assume the total primary computing load for the ship with no interruption, although some secondary and recreational functions (such as holodeck simulations) may be suspended.
Core elements are based on FTL nanoprocessor units arranged into optical transtator clusters of 1,024 segments. In turn, clusters are grouped into processing modules composed of 256 clusters controlled by a bank of sixteen isolinear chips. Each core comprises seven primary and three upper levels, each level containing an average of four modules.
Memory storage for main core usage is provided by 2,048 dedicated modules of 144 isolinear optical storage chips. Under LCARS software control, these modules provide average dynamic access to memory at 4,600 kiloquads/sec. Total storage capacity of each module is about 630,000 kiloquads, depending on software configuration.
The main cores are tied into the ship's optical data network by means of a series of MJL junction links which bridge the subspace boundary layer. There is a 12% Doppler loss in transmission rate across the boundary, but the resulting increase in processing speed from the FTL core elements more than compensates.
A network of 380 quadritonic optical subprocessors is distributed throughout both ship's sections, augmenting the main cores. Within the habitable volume of the ship, most of these subprocessors are located near main corridor junctions for easy access. While these subprocessors do not employ FTL elements, the distributed processing network improves overall system response and provides redundancy in emergency situations. Each subprocessor is linked into the optical data network, and most also have a dedicated optical link to one or more of the main cores.
The Main Bridge and the Battle Bridge each have seven dedicated and twelve shared subprocessors, which permit operations even in the event of main core failure. These bridge subprocessors are linked to the main cores by means of protected optical conduits, which provide alternate control linkages in the event of a primary optical data network failure.
Further redundancy is provided by dedicated short-range radio frequency (RF) links, providing emergency data communications with the bridge. Additional dedicated subprocessors can be installed as needed to support mission-specific operations.
Virtually every control panel and terminal within the ship is linked to a subprocessor or directly into the optical data network. Each active panel is continually polled by LCARS at 30 millisecond intervals so that the local subprocessor and/or the main core is informed of all keyboard or verbal inputs. Each polling inquiry is followed by a 42 nanosecond compressed data stream, which provides panel update information. This data stream includes any requested visual or audio information for panel output.
Short-range RF data links are available throughout the ship to provide information transmission to portable and handheld devices such as tricorders and personal access display devices (PADD). This integrated network of computers, subprocessors, and panels forms the nervous system of the ship and permits continuous realtime analysis of the ship's operating status. The network is specifically designed to permit independent operation of remaining system elements in the event of a wide variety of partial system failures.