importance in use cases like the mentioned e-mail push, but also for SMS delivery, and other data synchronisation processes between a central data base and a mobile device. Current approaches to this challenge are predominantly using software tokens[, [e.g.]{},]{}PKCS\#7, to secure message transport and storage. Such solutions however suffer from the drawback that an attacker can extract keys from memory during encryption or decryption of a data block. Smart cards are a more evolved approach, but in the mobile domain no standard has become prevalent.

![A centralised architecture[]{data-label="NOC"}](NOC_scenario.eps){width="40.00000%"}

Figure \[NOC\] illustrates the widely used, centralised push architecture. In its centre a Network Operation Center (NOC) performs all tasks regarding the communication to the mobile devices. The data destined for the mobile devices are stored in sources like mail servers. These sources excite the push server and deliver the data. Due to this activation the push server either requests a communication line to the mobile device managed by the NOC or delivers the data to the NOC which in turn stores the data until they are handed to the mobile device. From a company’s view the management costs are low as there is no additional effort needed to maintain[, [e.g.]{},]{}a special 