Machine type communications (MTCs) enable the communications of machines (devices) to machines over mobile networks. Besides simplifying our daily lives, the MTC business represents a promising market for mobile operators to increase their revenues. However, before a complete deployment of MTC over mobile networks, there is need to update the specifications of mobile networks in order to cope with the expected high number (massive deployment) of MTC devices. Indeed, large scale deployment of MTC devices represents an important challenge as a high number of MTC devices, simultaneously connecting to the mobile network, may cause congestion and system overload, which can degrade the network performance and even result in network node failures. Several activities have been led by 3GPP to alleviate system overload introduced by MTC. Most of the devised approaches represent only incremental solutions. Unlike these solutions, we devise a complete new architectural vision to support MTC in mobile networks. This vision relies on the marriage of mobile networks and cloud computing, specifically exploiting recent advances in network function virtualization (NFV). The aim of the proposed vision, namely LightEPC, is: 1) to orchestrate the on-demand creation of cloud-based lightweight mobile core networks dedicated for MTC and 2) to simplify the network attach procedure for MTC devices by creating only one NFV MTC function that groups all the usual procedures. By doing so, LightEPC is able to create and scale instances of NFV MTC functions on demand and in an elastic manner to cope with any sudden increase in traffic generated by MTC devices. To evaluate LightEPC, some preliminary analysis were conducted and the obtained analytical results indicate the ability of LightEPC in alleviating congestion and scaling up fast with massive numbers of MTC devices in mobile networks. Finally, a real-life implementation of LightEPC on top of cloud platform is discussed.