B2B Integration : A Practical Guide to Collaborative E-commerce

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Application B
Integration Patterns 51
Replication Replication
Server A Seiver B
Figure 3.2. — Example of data replication
Deliver Data 1 1 Deliver Data
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Database B Database C
that users can be guaranteed that the data in their data source is
consistent and accurate.
All the leading database vendors such as IBM, Oracle, Sybase,
Microsoft, Informix, Unisys and Ardent software provide replication
servers.
Architectures of data replication solution
The core architectures of data replication solution include:
• Primary site data replication;
• Bi-directional data replication; and
• Multi-site data replication.
Primary site data replication
In this architecture, there is a single, primary data source, known as the
primary or master site, which maintains the master data. The data is
replicated from this source to the other data sources (see Figure 3.3).
All the data replicas only provide read-only access to the data. All the