# An Architecture for the Performance Management of Smart Healthcare Applications
## 4 The PRIMUS Architecture
### Network Model  
PRIMUS considers applications with critical requirements, such as s-health intensive care and remote surgery. Both applications require low-latency and high-reliability. Reliability in this work means successfully transmitting and delivering packets without exceeding the maximum latency  
Figure 1: An overview of network slicing. supported by the application [4, 6]. However, unlike the literature, PRIMUS does not refrain from other applications such as telemedicine [49]. Table 2 presents the main s-health applications and requirements. These applications have been defined by the Next Generation Mobile Network Alliance (NGMN) [6] and 3 rd Generation Partnership Project (3 GPP) [5, 45]. In general, almost all s-health applications require reliable communications since patient health comprises a critical use case [6]. The most flexible applications, such as fitness and calorie counting, have no stringent requirements. Body temperature and diabetes monitoring consist of daily continuous monitoring applications. These applications collect specific vital signs and issue medical alerts when critical situations occur (e.g., extreme body temperature values). They support up to 125 ms latency [9]. In contrast, telemedicine applications demand high data rates and low-latency (10 ms). Therefore, PRIMUS needs to meet these requirements automatically through network slicing. PRIMUS takes into account a network model, as illustrated in Figure 2. The model encompasses the communication between smart devices and environments, such as smart home and smart hospitals, supporting new applications, particularly s-health. In the smart environments, the network infrastructure contains different devices generating network traffic to a gateway by wireless connection (e.g., Wi-Fi, Bluetooth, 5G). The edge devices involve smartphones, augmented reality on video games, laptops, smartwatches from the smart home, ambulance, wearable, and sensors from the smart hospital. We can have usual devices in both smart scenarios, e.g., smartphones. Each device contains applications running on it. PRIMUS receives as input the application identification from our previous work [21]. In the core network, devices involve base stations, routers, switches, and others. Such network model supports network slicing and virtualization techniques (NFV and SDN). Formally, let \(N=(1,...,n)\) be the set of tenants (e.g., end-users) that generates network traffic from a given application \(app\), where \(App=(1,...,app)\) is a set of applications. Hence, let \(v_{n,s}(t)\) be the traffic of an application associated with a slice \(s\) at tenant \(n\) during instant \(t\). Each network slice is responsible for traffic messages exchanged between hosts, considering application requirements. Hence, the slice \(s\) needs to achieve a set of requirements \(Q=\{q_{1},q_{2},...,q_{n}\}\) specific from the application \(app\). A set of available network resources \(R=(1,...,r)\), such as bandwidth and computing, are necessary to \begin{table}
\begin{tabular}{l c c c} \hline \hline
**Application Type** & **Latency** & **Bandwidth** & **Reliability** \\ \hline Telemedicine & \(\leq\)10 ms & \(\geq\)200 Mbps & - \\ Remote Surgery & \(\leq\)1 ms & 10 Mbps & 99.999\% \\ Diabetes/Temperature & \(\leq\)125 ms & 10 Mbps & - \\ Emergency Ambance & \(\leq\)1 ms & 10 Mbps & 99.999\% \\ Critical Care Monitor & \(\leq\)1 ms & 10 Mbps & 99.999\% \\ Remote Monitor & \(\leq\)10 ms & \(\geq\)50 Mbps & - \\ Smart Medication & \(\leq\)125 ms & \(\geq\)20 Mbps & - \\ \hline \hline \end{tabular}
\end{table} 
Table 2: S-Health and performance requirements. Figure 2: The PRIMUS network overview. achieve such requirements. Therefore, a given slice \(s\) is composed by virtual network resources \(r_{1},r_{2}...r_{n}\), network traffic \(v_{n,s}(t)\) and an associated user \(n\) and application \(app\) that demands some requirement \(q\). Moreover, each slice has one controller \(c\), from the set of controllers \(C=(1,...,c)\), managing the resources.