Resource Orchestration Strategies With Retrials for Latency-Sensitive Network Slicing Over Distributed Telco Clouds

Abstract

The new radio technologies (i.e. 5G and beyond) will allow a new generation of innovative services operated by vertical industries (e.g. robotic cloud, autonomous vehicles, etc.) with more stringent QoS requirements, especially in terms of end-to-end latency. Other technological changes, such as Network Function Virtualization (NFV) and Software-Defined Networking (SDN), will bring unique service capabilities to networks by enabling flexible network slicing that can be tailored to the needs of vertical services. However, effective orchestration strategies need to be put in place to offer latency minimization while also maximizing resource utilization for telco providers to address vertical requirements and increase their revenue. Looking at this objective, this paper addresses a latency-sensitive orchestration problem by proposing different strategies for the coordinated selection of virtual resources (network, computational, and storage resources) in distributed DCs while meeting vertical requirements (e.g., bandwidth demand) for network slicing. Three orchestration strategies are presented to minimize latency or the blocking probability through effective resource utilization. To further reduce the slice request blocking, orchestration strategies also encompass a retrial mechanism applied to rejected slice requests. Regarding latency, two components were considered, namely processing and network latency. An extensive set of simulations was carried out over a wide and composite telco cloud infrastructure in which different types of data centers coexist characterized by a different network location, size, and processing capacity. The results compare the behavior of the strategies in addressing latency minimization and service request fulfillment, also considering the impact of the retrial mechanism.

Resource Abstractions in NFV Management and Orchestration: Experimental Evaluation

“…The higher-layer Service Orchestrator, using the advertised (abstracted) NFVI, seeks the unused resources embedding the VNFs into the PoPs as well as fulfilling the VLs requirements (i.e., bandwidth and latency) over the LLs among those PoPs. This problem is usually referred to as VNF placement/embedding which has received notably attention in the last years [19], [9]. In general, NS requests are modelled as service function chains (SFCs) [20].…”

“…To overcome this, there are several approaches in the literature based on heuristics, integer linear programming, machine learning, which exploits different techniques such as parallelism of VNFs, VNF decomposition, flexible VNF ordering, etc. [7], [9], [19], [21], [22], [24].…”

Dynamic Virtual Network Embedding with Latency Constraint in Flex-Grid Optical Networks

“…The number of available frequency slots |𝐹𝑆| for a bandwidth 𝐵 𝑠 with a certain capacity of optical fiber link is given by [28]: (24) where 𝑆𝑊 represents the 𝐹𝑆 width (equal to 12.5 𝐺𝐻𝑧). The number of occupied frequency slots |𝑂𝐹𝑆| which achieves the requested bandwidth demands 𝐵 𝑣 is given by [28]:…”