Geographically dispersed Parallel Sysplex architecture using optical wavelength-division multiplexing

Since its introduction in 1994, the Parallel Sysplex architecture for mainf rame computer systems has attracted a great deal of interest because of its high performance, continuous availability, scalability, and lower cost of ownership. Recently, it has become possible to interconnect the building bl ocks of a Parallel Sysplex (host processor, coupling facility, sysplex time r, and disk storage) at extended distances using fiber optic data links. In particular, optical wavelength-division multiplexing (WDM) has been an ena bling technology for the extension of this architecture to a geographically dispersed Parallel Sysplex (GDPS). We describe the use of WDM in GDPS conf igurations, including distance limitations and typical performance consider ations. Experimental results of testing a GDPS with WDM channel extensions up to 40 km are presented, and some test results on the IBM 9729 Optical Wa velength Division Multiplexer used in these configurations are also discuss ed. (C) 1998 Society of Photo-Optical Instrumentation Engineers. [S0091-328 6(98)01312-9].