# Towards Efficiently Provisioning 5G Core Network Slice Based on Resource and Topology Attributes
## 1 Introduction
The slice provisioning problem in 5G network slicing is essentially the same as the traditional virtual network embedding (VNE) problem [15] in network virtualization (NV) (we rename the virtual network embedding (VNE) problem to slice provisioning problem in network slicing). Most previous VNE methods have only considered the resource attributes of the network and ignored its topology attributes to allocate physical resources to virtual network requests. Notwithstanding that several approaches consider the resource and topology attributes, the local and global resource attributes as well as the local and global topology attributes are not reasonably defined, which causes these methods to be not effective. Based on the above considerations, we have designed a heuristic 5G core network slice provisioning strategy based on the local and global network resource attributes and topology attributes including the product of the CPU of the node and all its adjacent links, i.e., local resource attribute, the minimum bandwidth of the links in the shortest path of the node to all other nodes and the minimum CPU of the nodes along the shortest path, i.e., global resource attribute, node degree centrality, and node closeness centrality. When a 5G core slice request arrives at the slice provisioning system, the system uses resource attributes and topology attributes to perform comprehensive node evaluation and ranking, and then slice nodes are provisioned according to the ranking results. Next, slice links are provisioned using the \(k\)-shortest path algorithm. Our contributions are summarized as follows:  
* We propose a network node scoring and ranking method by jointly considering local and global network resource and topology attributes. Specifically, we introduce a _cooperative provisioning coefficient_ for the physical node scoring to enhance the efficiency of provisioning slice links. * We design a two-stage 5G core slice provisioning algorithm, called RT-CSP, which includes a heuristic slice node provisioning algorithm and a \(k\)-shortest path based slice link provisioning algorithm. In the first stage, slice nodes are provisioned in a heuristic manner in accordance with the network node ranking results. In the second stage, the \(k\)-shortest path algorithm is used to provision slice links. * To further improve the performance of RT-CSP, we propose RT-CSP+ slice provisioning algorithm based on our designed _miniMaxBWlliiHops_ strategy in the slice link provisioning stage. The strategy selects the physical path which has the minimum product of the maximum link bandwidth utilization and its hop count from the candidate physical paths obtained by the \(k\)-shortest path algorithm to host the slice link. * We verify the performance of our proposed algorithm through extensive simulations and prove that our algorithm can increase the slice request acceptance ratio and, hence, the revenue of physical network provider. The remainder of the paper is organized as follows. Section 2 discusses the related work. In Section 3, we describe the 5G core slice provisioning problem and present the system model. The heuristic 5G core slice provisioning algorithms based on network resource attributes and topology attributes are presented in Section 4. In Section 5, we present simulation experiments and the experimental results. Finally, the conclusions and future work are laid out in Section 6.