3.0 Data Synchronization and Replication
The most potential and perilous
problem arises when data inconsistency is observed between the
mobile device and SAP system. To avoid such situations, a SAP
business transaction should result in updating the enterprise data
residing on SAP system as well as mobile device.
To implement this, SAP Mobile
Engine ensures the availability of critical business data to the
mobile device. The mobile device user makes desired changes to the
data. This data is updated in the data container [The logical unit
where data is stored] of the mobile device and when substantial
number of modifications are made to data, it is updated in the SAP
database. The Mobile Engine Synchronization Layer is responsible for
this functionality and maintains data consistency (See Figure 4).
Figure 4: Data
Synchronization
Data container exists on one place
only in the mobile engine and hence during the process of data
transfer, there is no possibility of a data container being lost in
the engine. Moreover, data is not handed over to the other container
if connection gets lost during synchronisation process between
mobile device and SAP system. In such situation the data container
stays on the mobile device and is sent automatically with next
synchronization. It also ensures that data has been transferred
successfully to the SAP system and vice-versa. Synchronization layer
also provides data security by using HTTP with Secure Sockets Layer
(SSL).
The Replication layer plays a
major role by monitoring user synchronization process and uses Web
Application Server (WAS) to determine data, which is assigned to
multiple mobile device users.
