# Modeling and Analyzing Preemption-Based Service Prioritization in 5G Networks Slicing Framework
###### Abstract  
The Network Slicing (NS) technology, recognized as one of the key enabling features of Fifth Generation (5G) wireless systems, provides very flexible ways to efficiently accommodate common physical infrastructures, e.g., Base Station (BS), multiple logical networks referred to as Network Slice Instances (NSIs). To ensure the required Quality of Service (QoS) levels, the NS-technology relies on classical Resource Research (RR) or Service Prioritization schemes. Thus, the current paper aims to propose a Preemption-based Prioritization (PP) scheme \"merging\" the classical RR and Service Prioritization schemes. The proposed PP-scheme efficiency is evaluated or estimated given a Queueing system (QoS) model analyzing the operation of multiple NSIs with various requirements at common 5G BSs. As a key result, the proposed PP-scheme can provide up to 100% gain in terms of blocking probabilities of arriving requests with respect to some baseline. 5G; slicing; priority; pre-emption; service; isolation; GBR; requirement; queueing; resource +
Footnote †: journal: _Future Internet_  
Streaming, etc. As for BG category, it regroups the services that only require minimum bit rate, e.g., Social Networking, Web Surfing or Browsing, etc. Lastly, BE category regroups the services that do not require minimum and/or maximum bit rates, e.g., Smart Metering, Email, etc. The main objective of NS-technology is the efficient resource use while avoiding network downtimes and ensuring the required NSIs isolation [14; 19; 20; 21]. In that way, load bursts in some NSIs cannot affect the QoS in other neighboring NSIs. The outlined by [PERSON] classical approach to finite Resource Sharing introduces five Resource Allocation schemes from Complete Partitioning to Complete Sharing through schemes with Maximum Queue Length and Minimum Allocation [22; 23]. This approach, based on the Resource Reservation (RR) scheme, cannot allow reserved resources use even when network downtimes occur. Thus, the approach cannot ensure the efficient resource use in 5G systems. Moreover, the Service Prioritization scheme required in 5G networks for heterogeneous traffic service is not considered in the approach. In 5G networks, the RR and Service Prioritization schemes can contribute to NSIs isolation [24; 25; 26; 27; 28; 29]. Given the traffic intensities, the RR-scheme is relatively efficient and simple to implement, providing guaranteed minimum and/or maximum data rates to NSIs at common 5G BSs. The drawback is that this scheme can prove inefficient and limit the network flexibility to accommodate any new demand. In contrast, inherently dynamic and allowing efficient resource use, the Service Prioritization can pave the way to a solution, though hierarchy creation among the NSIs cannot enforce the required isolation. Given what precedes, the paper [26] focuses on three important features of NS-technology: flexible priority-based performance isolation, fair QoS-aware resource allocation among users and efficient resource use. A Queueing System (QS) model to analyze the operation of three NSIs at common 5G BSs is proposed. The NSIs are considered to each support a unique service type from the standardized GB, BG, and BE categories. The authors assumed uniform data rate requirements for starting service of users at the NSIs. Thus, is proposed for heterogeneous traffic service a NS scheme that can bolster the NSIs performance isolation while maintaining efficient resource use at the Complete Sharing level. In addition, the paper [25] proposes a QS model to estimate the End-to-End (E2E) mean packet delay of the NSIs. The 5G infrastructure performance in industrial environments is analyzed with a focus on the instantiated NSIs isolation degree. A reasonably complete and realistic setup is considered, given inputs parameters from experimentation and simulation. The aim is to highlight the features enabled when using segregated NSIs with reserved resources to service the traffic generated by various production lines at a factory floor.