The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part B4. Beijing 2008 
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2. METHODS 
2.1 Data storage (at the ZAIK/RRZK) 
A persistent, sustainable, secure storage of data is very 
important for all kinds of projects that handle data. This has to 
be organized in a clearly arranged and ordered structure. 
Moreover only authorized users should be permitted to access 
the data storage. Furthermore, it is essential to backup or 
archive data to ensure the recovery of destroyed data. Hence e.g. 
the German Federal Office for Information Security (BSI) 
follows the just given principles for the storage and 
management of data (BSI 2008). Considering the mentioned 
facts and guidelines of the DFG, the cooperation with a 
computing center is indispensable for an interdisciplinary 
project. 
The storage of data at the Regional Computing Center 
(RRZK)/the Center for Applied Computer Sciences (ZAIK) of 
the University of Cologne is organized in different stages. 
These are the Storage-Area-Network (SAN) based Disk Storage, 
the Andrew File System (AFS) and the High Performance 
Computing (HPC) - File System (see Figure 1). 
Figure 1. Data storage at the ZAIK/RRZK (Kalle 2005) 
In this contribution, the focus will be on AFS, a distributed 
networked file management system (file database). Besides 
sharing and synchronizing federated file storage, main 
advantages of the AFS are aspects like security, scalability, and 
user administration by an Access Control List (ACL). 
Furthermore, AFS supports location inference, cross platform 
access (e.g. UNIX, Linux and Microsoft Windows) and simple 
archive and data backup (AFS 2008). 
2.2 Databases 
The persistent, consistent and efficient management and storage 
of a huge amount of data sets is the central duty of a Database 
Systems (DBS). A DBS is a combination of a database (DB) 
and a Database Management System (DBMS) (Elmasri and 
Navathe 2005). The real storage of data operates at the DB. The 
DBMS is the software that enables the management of data in a 
specified data model. The characteristic properties or rather 
requirements of a DBS are data independence, central data 
management, multiuser access, data security, data integrity 
(redundance-free data storage), access control, processing of 
requests, and operating system independence (Brinkhoff 2008). 
Data models are described in several structures. In this context 
relational and object-relational models and databases are 
important. Relational database models are identified with 
connected database tables that store the data like IBM DB2, 
Microsoft Access or MySQL. Object-relational database models 
manage objects that are stored in linked relational data tables 
like Oracle Spatial or PostgreSQL (Tiirker and Saake 2005). 
They are qualified to be geodatabase systems on condition that 
they have a corresponding extension (Brinkhoff 2008). 
2.3 Metadata 
The term metadata describes data that contain information 
about data e.g. quality, author, location, and year of publication 
for a book. The common use of metadata is to describe data and 
enable a better search. For more explanations on metadata and 
the importance of see Yeung (2007). 
The metadata structure should follow recent standards and 
principles. These are basically spatial data standards from the 
Open Geospatial Consortium (OGC), the International 
Organization for Standardization (ISO), the Dublin Core 
Metadata Initiative (DCMI), and the World Wide Web 
Consortium (W3C) (Bartelme 2005 and Nogueras-Iso et al. 
2005). For example the geo-metadata follows the guidelines of 
ISO Norm 19115 (IS019115 2003). 
2.4 Web-Interface and WebGIS 
The main duty of a web-interface is the representation of 
information at the World Wide Web. The implementation of a 
web-interface is predominantly carried out with the platform 
independent markup language HTML/XHTML ((Extensible) 
Hyper Text Markup Language). In addition the client-side 
scripting language PHP (Hypertext Preprocessor) is used for 
dynamic web pages as well as CSS (Cascading Style Sheets) to 
describe the style of the web-interface. A combination of PHP 
and SQL (Structured Query Language) is used to customize the 
interaction between the database and the web-interface. The 
encrypted SSL (Secure Sockets Layer) technology including a 
digital certificate ensures a secure communication via internet 
e.g. for web browsing or data exchange (Open SSL 2008). 
In recent years the presentation of GIS and cartographic 
functionalities (web mapping) in the internet became more and 
more important (Asche and Herrmann 2003). Hence a WebGIS 
is absolutely essential to visualize, manage, and analyze spatial 
geodata within a web-interface. ESRI’s ArcGIS Server 
connected with ArcSDE (Spatial Database Engine) provides an 
opportunity to realize a WebGIS (ESRI 2008). 
3. TR32 DATABASE DESIGN 
The essential duty of the TR32 data management SP is to 
enable data storage and exchange for different SPs. In addition 
backup functionalities have to be implemented as well as 
corresponding metadata for the project data. With regard to the 
project duration, it is important to design a stable and 
sustainable system, called the ‘TR32 Database’ (TR32DB). 
As a result of the interdisciplinary background of the TR32, the 
TR32DB stores a multiplicity of different data: measured and 
purchased project (geo-) data. The measured project data 
comprise data that are collected of the various TR32-SPs. The