## 3 Novel Taxonomy for SSNs
### High Level Virtualization
#### 3.2.2 HLV Using System Level Virtualization Solutions  
This is the second branch of HLV that was applied over the whole network to controls different authorities of shared resources, it has two roles: the first one is controlling and managing different authorities for different federated WSNs, which are united to create a large federated WSN, and the second one is controlling and managing different authorities for resulting small scale VSNs, which are produced due to participation of a WSNs. System Level Virtualization based on Federation:  
Federated SSNs occur when multiple WSNs from different administrative authorities are united into a single SSN. As shown in Figure 26a, they are usually connected through the internet. It provides a global administrative policy to manage and control the shared resources from different administrative authorities; it faces two major issues, the first is the need for a resource management mechanism that is responsible for describing, discovering, and reserving the allowing shared resources, the second is the need to provide a way for concurrent tasks allocation and scheduling. Finally, it requires authentication, authorization, and accounting (AAA) to control access to the SSN's resources, enforcing policies, auditing usage, and providing the information that is necessary to bill for services. These combined processes are important in effective network management and security. This section will briefly present federated examples of SSNs. Figure 26: SSNs. (**a**) Federation (**b**) participation. Figure 25: DRAGON’s phases. * **Global Environment for Network Innovations (GENI)**: It is a federated virtual laboratory for networking and distributed systems research and education project. It introduces a novel suite of infrastructure designed to support experimental research in network's science and engineering [64], starting from a new research on networks and distributed systems design to the theoretical underpinnings of network science, network policy and economics, societal values, and the dynamic interactions of the physical and social spheres with communications networks [65; 66]. The U.S. National Science Foundation (NSF) funded GENI. It is composed of a broad set of heterogeneous resources, each owned and operated by different entities (called aggregate providers), as can be seen in Figure 27, by joining the GENI federation, these aggregate providers make their resources available to GENI experimenters, while still maintaining a degree of control and trust that these resources will be used in a responsible and secure manner. The federation of testbeds is based on the concept of testbed virtualization and virtual links between them. GENI Network architecture is shown in Figure 28. It consists of: (1) The control plane, which is used to discover reserve, access, program, and manage GENI's computational and communication resources; (2) The data plane, which is setup depending on the requirements of the experiment. GENI offers some features to users for facilitating the control of the experiment, such as: (1) Slicing the network, this feature allows multiple experiments to share the same physical infrastructure, while keeping isolation among them; (2) Deep programmability, which gives the programmers the ability to determine the packet paths through the experiment; (3) Network federation and stitching, this feature organizes the shared resources among different network providers; (4) GENI wireless networks, which provide a wireless base station that connects the local rack and the rack through the rest of the network; and finally, (5) Connecting campus resources to GENI. GENI proposes an Open Resource Control Architecture (ORCA) framework for federated infrastructure services, it consists of an Aggregate Manager (AM), Slice Manager (SM), and broker.