Test bed Cost Model for Digital Preservation (T-CMDP)

Property Description                                                                                                                           
ID 1
Name Test bed Cost Model for Digital Preservation
Creator & Funding Developed by The National Archives of the Netherlands as part of the digital preservation test bed project
Status The latest versions of the model and the computational model spreadsheet (Version 1.0) are from 2005; version 1.2 30-Aug-2005 for the cost model tool.
Purpose The purpose is to estimate the costs of long-term preservation and compare the costs involved in applying different preservation approaches.
Information assets Texts, emails, spreadsheets, databases
Activities Ingest, Archival Storage, Data Management, Administration, Preservation Planning (normalisation at ingest and migration after 20 years)
Resources Capital cost, labour cost (6 types), fixed cost, operational cost
Time Present, future
Variables Labour salaries (6 types), capital cost (building space, hardware and software, clients, servers, databases, storage, 'archive system'), migration frequency, number of assets
Type of tool Analysis tool, implemented in spreadsheet
Availability of tools The spreadsheet is no longer available at the National Archives of the Netherlands, but can be found on the Internet Archive
References Slats, J. and Verdegem, R. (2005) 'Cost Model for Digital Preservation,' Proceedings of the IVth triennieal conference, DLM Forum, Archive, Records and Information Management in Europe: http://dlmforum.typepad.com/paper_rem


T-CMDP gives a list of cost indicators, which influence the total cost of preservation. It also includes a computational model for calculating the total cost of preservation.

The model defines five high level cost indicators:

  • cost of a digital repository and preservation system
  • personnel costs
  • cost of developing or acquiring software and strategies
  • cost of performing preservation actions, and
  • other costs

These cost indicators are used to estimate the total cost of preservation and expresses it as money and time. The model is based on OAIS terminology. It examines migration on request and migration to XML (preservation format) and emulation using the Universal Virtual Computer (UVC).

Included in the model is the cost of the digital archival system (a digital depot or repository) and functionality for the long term preservation of digital records; personnel costs, such as the cost of the development or procurement of software and methods for the preservation of digital records; the cost of the actual storage of digital records; and other factors that exert an influence on the total cost.

The tool is a structured with: a costs basis (labour, capital); operational cost: labour cost per preservation activity per asset type (email, text, spreadsheet, database); activities: Acquire and appraise, metadata, repair, develop preservation approach (gather req. and develop approach), preserve and evaluate.

The model is straightforward and easy to use. However, it’s out of date and does not breakdown activities in sufficient detail. It could be updated to capture greater detail but the LIFE work probably has already done this so there isn't much benefit in revising this model further.