## 2 State of the Art
### RINA-Based Networks
\begin{table}
\begin{tabular}{c c} \hline \hline
**Message Name** & **Purpose** \\ \hline M\_CREATE & Create a RIB object \\ \hline M\_CREATE\_R & Response to M\_CREATE, carries the result of a create request \\ \hline M\_DELETE & Delete a specified object \\ \hline M\_DELETE\_R & Response to M\_DELETE, carries the result of a deletion attempt \\ \hline M\_READ\_R & Response to M\_READ, returns the result and (possibly incomplete) value of the object \\ \hline M\_WRITE & Writes a specified value to a specified object \\ \hline M\_WRITE\_R & Response to M\_WRITE, carries the result of a write operation \\ \hline M\_START & Start the operation of a specified application object, typically used when the object has operational and non-operational states \\ \hline M\_START\_R & Response to M\_START, indicates the result of the start operation \\ \hline M\_STOP & Stops the operation of a specified application object, typically used when the object has operational and non-operational states \\ \hline M\_STOP\_R & Response to M\_STOP, indicates the result of the stop operation \\ \hline \hline \end{tabular}
\end{table} 
Table 1: CDAP messages and purpose. These large-scale scenarios bring diverse and challenging requirements, such as a broader range of performance, cost, security protection, and mobility management. Network slicing has emerged as a potential approach to fulfill such requirements [26]. In [27] is presented what the authors called IPC Virtual Private Network (VPN) (Inter-Process Communication Virtual Private Network) slicing. IPC VPN is a RINA-based network slicing solution that focuses on connecting groups of applications instead of connecting endpoints with IP or Media Access Control (MAC) addresses. The goal is no longer focused on devices and physical location but on providing an isolated and fit-for-purpose connectivity domain to instances of distributed applications, regardless of their physical location. Following this IPC VPN slicing approach, recent research has been conducted in the framework of the Open-VERSO project [28], proposing RINA L2 VPN, a virtual networking solution to provide tailored connectivity to virtualed NFs. In [26], RINA L2 VPN is briefly presented as a novel network slicing solution, and it is compared with other network slicing solutions. Currently, a RINA L2 VPN slicing solution is being implemented, and its preliminary results were presented in [29]. In such an implementation, performance is one of the key features we have in mind to support the transmission of high loads, e.g., for media use cases running in 5G and beyond 5G infrastructures. In this regard, the current implementation, as proved in [29], overcomes by 30-50 times the performance provided by IRATI [22]--the most generic and mature RINA implementation to date--in terms of speed--packets processed per second--and throughput. The high throughput result was achieved by implementing the data path with netmap [30] instead of the Unix kernel stack. The advantages of a netmap-based implementation are twofold. First, it provides relatively high throughput with a significant amount of flexibility; since the implementation of the software program is only bound by the constraints of compute hardware instruction sets. Second, the diversity of supported available hardware platforms--Linux and FreeBSD systems.