"In 2003 the previous consortium franchisee Connex Melbourne in conjunction with the Department of Infrastructure embarked on a stabilisation program for the principal train control facility in Melbourne. The facility is commonly known as METROL. The Train Control System located at METROL provides a remote control facility for some signalling infrastructure which is the principal means of operation in the Melbourne inner metropolitan area, currently under the Metro Trains Melbourne franchise (MTM)."
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"In this particular train control application it has enabled the life extension of mature train control software, originally designed to run on a now life expired DEC PDP-11 platform to be migrated to a PC based platform. The original application software core is maintained 100% and remains unaltered running inside the new platform. This approach has allowed the re-use of the fully de-bugged Train Control application software as the core of the system."