This document describes the proposed computing model for the initial phase of operation of the European XFEL (EuXFEL) facility. In recognition of the overlap and interdependence of online data acquisition (DAQ) and offline data management (DM), both online and offline handling will be reviewed. The DAQ scope covers the control and readout systems in the photon beam lines, experimental hutches, laser and computing rooms in the experimental hall, and interaction with the electron machine control

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... ystem. It does not include office computing requirements. The DM scope covers offline systems downstream of the DAQ required for secure on-site data storage and analysis, and remote access to the data. Specific DAQ and DM hardware and software solutions and the IT services required, e.g. networking, access control, etc., by both are described. The scale, manpower and financial cost of the system based on the current understanding of EuXFEL operation are estimated. The understanding of EuXFEL operation will evolve continuously and will require modification of this note. This version of the DAQ and DM computing TDR is for public use and Appendix B, which contains cost, manpower and time line estimates, has been removed.