A Fair Sharing Approach for Micro-Services Function Chains Placement in Ultra-Low Latency Services

The evolution of Internet services, such as drone piloting or metaverse, tends toward ultra-Low Latency (LL) requirements, thus inducing new challenges in the placement of Service Function Chains (SFCs) deployed over virtualized infrastructures. On the one hand, this challenge requires novel optimization means. In particular, decomposing monolithic Network Functions (NFs) into micro-services acts as a promising approach thanks to their mutualization and highly parallelization characteristics, which makes it possible to reduce the length of the service chains and consequently their execution latency. On the other hand, since a core feature of the Internet relies on the coexistence of several types of services, fair sharing of resources between LL SFCs and Best Effort (BE) services appears as a core question to address. In this paper, we present an optimization model, which leverages the characteristics of micro-services to place and chains different types of SFCs in a common infrastructure. We first consider the case of standalone LL SFCs to demonstrate the benefits of mutualization and parallelization. Then, we consider the more complex situation of a fair cohabitation between BE and LL SFCs. This leads us to propose and compare three variants of our initial objective function, all supporting different resource sharing strategies. By confronting our model to several realistic scenarios in terms of topology and service function chains, we demonstrate (1) to what extent it improves the overall performance of SFCs by minimising the gap between expected and actual latency, and (2) it allows LL and BE SFCs to coexist without impacting the latency of the deployed LL SFCs.