Mobile soft device
Mobile soft device or MSD is a mobile communication service software package that executes on mobile devices such as smartphones and tablets. An MSD is commonly implemented as a smartphone app.
A mobile soft device is integrated with the core mobile network and its voice call, SMS and MMS services in the same way as a normal mobile phone (with an installed SIM card). Therefore an MSD uses the mobile voice call, SMS and 3GPP MMS services as an integrated part of the overall service provided to the end user.
As a result, an MSD makes it possible to establish a real-time communication link between two end points even if neither end point is connected to the Internet. In contrast, other smartphone communication apps, such as OTT services, often require both sides to be connected to the Internet in order to establish a real-time communication connection between the two end points.
A further result of the mobile network integration is that a mobile soft device does not require both end points to have an MSD installed in the mobile device in order to fully use voice, SMS and multimedia services. In contrast, an OTT mobile communication app often requires that both end points have the same app installed.
An MSD can thus be used to establish a real-time communication with any other mobile device, anytime and anywhere. This would not be possible with an ordinary OTT smartphone communication app.
The MSD software program executes on mobile hardware devices, such as smartphones or tablets, on top of the mobile device operating system, for example Apple iOS, Google Android or Windows Mobile. The MSD does not need to be installed onto a device with a physical SIM, which is traditionally used to identify and authenticate the particular mobile hardware device and the particular user. An MSD has a virtual SIM card function implemented by software and is therefore not dependent on a physical SIM card to authenticate the mobile user.
An MSD can be used by a mobile network operator or an MVNO to provide OTT services similar to Skype, Viber and WhatsApp (in March 2013), with the added benefit of using the integration with the core mobile network to provide these services anytime and anywhere. In addition, the MSD can provide completely new services as it has access to mobile subscriber data and other mobile network infrastructure, something traditional OTT services generally do not have.
In the special case of voice calls, text messaging and 3GPP MMS, the MSD can be viewed as a mobile soft phone in contrast to a hardware phone device. The cost for a mobile operator to reach new customers, or to distribute physical mobile phones and SIM cards, is usually high. As the MSD is typically distributed over app stores at virtually no cost to the mobile operator, the MSD concept is expected to reshape the mobile industry.
MSD and VoLTE
MSD also has significant relevance for 3GPP IMS in general and Voice-over-LTE VoLTE. VoLTE is generally expected to provide an IP voice quality that is superior to other voice services over Internet. As the MSD is a software application executing on top of a mobile hardware device operating system, the MSD can be used to introduce VoLTE services even before the hardware device itself has VoLTE support. By moving the voice services from the mobile legacy net LTE, the mobile operator can consolidate the network technologies by phasing out 2G (and even 3G) networks and having all services carried over 4G and LTE networks even before the device industry has caught up with VoLTE support. Such a network technology consolidation will have a significant impact on the mobile network operations cost.