You are presented with multiple paper abstracts, alongside the associated literature review and chapter titles. Given the provided information, you are going to do a literature review. Please generate a coherent literature review that synthesizes the content, draws connections between different works, highlights major findings, and identifies any gaps in the existing research.

Literature Review Title: Towards Efficient Mobile M2M Communications: Survey and Open Challenges 
Chapter Title:  ETSI M2M Architecure 
1. Abstract of Cited Paper (BIB001):  E-health has raised a great deal of expectations on improving the quality of health services while simultaneously enabling health services cost reductions. To advance towards those visions, it is imperative to gain the trust of the involved stakeholders, doctors and other medical personnel, patients, families, health care providers and regulators. Even though one critical requirement is interoperability among the various systems involved, currently existing solutions are still vertical silos to a large extent. In this paper, we present an E-health solution that results from the integration of components that comply with rising standards at the various levels of the ICT infrastructure: Machine-to-Machine (M2M) communications for interconnecting devices and services, Health Level 7 (HL7) for communicating with health platforms and openEHR for data semantics, storing and making data available. Concretely, we provide an interoperable and extensible e-health service following these three uprising standards and present the architecture design. We map the service to the various components of the infrastructure building blocks, thus demonstrating how the integration can be successfully accomplished. We are currently developing a prototype solution to be used in a pilot project with 15 elders.

Literature Review:
The ETSI M2M architecture is currently the reference architecture for global, end-to-end, M2M service level communications, and is being adopted by main European telcos. The system architecture is based on current network and application domain standards, and it is extended with M2M Applications and Service Capabilities layers (SCLs). SCLs are Service Capabilities (SCs) on the Network domain, M2M Device, or M2M Gateway. SCs provide functions to be shared among different M2M applications. The functions of a SCL include, but are not limited to, registration of applications, provision of means for storage, policy-based selection of communication means for information delivery, support for multiple management protocols, or support of remote management of gateways and devices  . Figure 1 shows the high level ETSI M2M system architecture as defined in ETSI Technical Standard (TS) 689  . The key entities in M2M are  : The M2M Device domain is formed by M2M devices, M2M Area Networks, and M2M gateways. The M2M devices can connect directly to the Network and Application domain using the Access Network, or they can connect first to an M2M gateway using the M2M Area Network. In the first case, the devices run an M2M application and have an M2M SCL. In the latter, the M2M gateway runs an M2M application and an SCL, and provides access to the Access Network for the M2M Device, acting on its behalf, since the M2M Device has only an M2M Application running, but no SCL, and it is not compliant with ETSI. The Area Network provides connectivity between M2M devices and M2M gateways, and can be built on Bluetooth, UWB, ZigBee, M-BUS, or IEEE 802.15.4 technologies. The TS also specifies several interfaces not shown in the figure. The interface between an M2M Application in the M2M Device Domain and the M2M SC in the Network and Application Domain is termed mIa. The interface between an M2M Device or M2M Gateway and the M2M SC in the Network and Application Domain is named mId. Finally, the dIa interface is defined between an M2M Application in an M2M Device or M2M Gateway and the M2M SC at the same device. To better illustrate some entities, we describe a storyboard and map it in M2M, similar to BIB002 . Jonathan is concerned with his well-being. He is an elderly person and needs to control his heart condition. During his daily life he wears a wearable monitoring system that monitors his heart rate. Every morning, he picks up his smartphone, which connects to the wireless sensor to retrieve the measurements. These measurements are stored online, enabling a service that later provides his doctors access to his heart rate history. Figure 2 shows an overview of this storyboard. In an M2M ecosystem, Jonathan, a user, connects his smartphone, acting as an M2M Gateway, to collect information from sensors, M2M devices, over Bluetooth (the M2M Area Network technology) using an M2M Application. The M2M Gateway sends the data using 3G to a Network SCL (NSCL), which main function is to manage the data. In this case, the NSCL stores the data for backup storage purposes and sends the content to a medical Network Application. The M2M Management functions are all the functions required to manage M2M Applications and M2M SCs in the Network and Applications Domain, and the Network Management functions are all the functions required to manage the access, core, and transport networks BIB001 . The management functions include performance management, configuration management, fault management and software and firmware upgrading management. M2M Application life cycle management includes installing, removing, and upgrading applications in an M2M Device or Gateway. M2M service management includes configuration management for the M2M SCs in the M2M Device or Gateway. M2M Area Network management includes configuration management for the M2M Area Networks. M2M Device management includes the configuration management of the M2M Device or Gateway. In ETSI M2M, the M2M service platform is a horizontal middelware, thus applications share common environments, infrastructure, and network elements. To ensure interoperable M2M networks and services, M2M should be agnostic of technologies.