Provisioning Ultra-Low Latency Services in Softwarized Network for the Tactile Internet

The Internet has made several giant leaps over the years, from a fixed to a mobile Internet, then to the Internet of Things, and now to a Tactile Internet. The Tactile Internet is envisioned to deliver real-time control and physical tactile experiences remotely in addition to conventional audiovisual data to enable immersive human-to-machine interaction and allow skill-set delivery over networks. To realize the Tactile Internet, two key performance requirements, namely ultra-low latency and ultra-high reliability need to be achieved. However, currently deployed networks are far from meeting these stringent requirements and cannot efficiently cope with dynamic service arrivals/departures and the significant growth of traffic demands. To fulfill these requirements, a softwarized network enabled by network function virtualization (NFV) and software-defined network (SDN) technologies is introduced as a new promising concept of a future network due to its flexibility, agility, scalability and cost efficiency. Despite these benefits, provisioning Tactile Internet network services (NSs) in an NFV-based infrastructure remains a challenge, as network resources must be allocated for virtual network function (VNF) deployment and traffic routing in such a way that the stringent requirements are met, and network operator’s objectives are optimized. This problem is also well-known, as NFV resource allocation (NFV-RA) and can be further divided into three stages: (i) VNF composition, (ii) VNF embedding/placement and (iii) VNF scheduling. This thesis addresses challenges on NFV-RA for Tactile Internet NSs, especially ultra-low latency NSs. We first conduct a survey on architectural and algorithmic solutions proposed so far for the Tactile Internet. Second, we propose a joint VNF composition and embedding algorithm to efficiently determine the number of VNF instances to form a VNF forward graph (VNF-FG) and their embedding locations to serve ultra-low latency NSs, as in some cases, multiple instances of each VNF type with proper embedding may be needed to guarantee the stringent latency requirements. The proposed algorithm relies on a Tabu search method to solve the problem with a reasonable time. Third, we introduce real-time VNF embedding algorithms to efficiently support ultra-low latency NSs that require fast service provisioning. By assuming that a VNF-FG is given, our proposed algorithms aim to minimize the cost while meeting the stringent latency requirement. Finally, we focus on a joint VNF embedding and scheduling problem, assuming that ultra-low latency NSs can arrive in the network any time and have specific service deadlines. Moreover, VNF instances once deployed can be shared by multiple NSs. With these assumptions, we aim to optimally determine whether to schedule NSs on already deployed VNFs or to deploy new VNFs and schedule them on newly deployed VNFs to maximize profits while guaranteeing the stringent service deadlines. Two efficient heuristics are introduced to solve this problem with a feasible time

A Predictive Framework for Haptic Enabled VR-based Remote Phobia Treatment in Cloud/Fog Environment

The emerging Tactile Internet aims to transmit the modality of touch in addition to the conventional audiovisual signals, thus converting the content delivery networks into skill-set delivery networks. An interesting example of immersive, low-latency Tactile Internet applications is haptic-enabled virtual reality (VR), where an extremely low latency of less than 50 ms is required. In this paper, we consider a recently proposed fog-based haptic-enabled VR system for remote treatment of animal phobia. Specifically, we address the problem of excessive packet latency as well as packet loss, which may result in quality-of-experience (QoE) degradation. Toward this end, we aim to use machine learning to decouple the impact of excessive latency and extreme packet loss from the user experience by utilizing our proposed edge tactile learner (ETL), which is responsible for predicting the zones touched by the therapist and then delivering it to the patient fog domain immediately, if needed. The simulation results indicate that our proposed predictive method outperforms two benchmark algorithms in terms of accuracy and prediction time

Ensuring Reliability and Low Cost When Using a Parallel VNF Processing Approach to Embed Delay-Constrained Slices

© 2004-2012 IEEE. Slices were introduced in 5G to enable the co-existence of applications with different requirements on a single infrastructure. Slices may be delay-constrained for mission-critical applications such as Tactile Internet applications. When delay-constrained slices are implemented as collections of virtual network function (VNF) chains, a key challenge is to place the VNFs and route the traffic through the chains to meet a strict delay constraint. Parallel VNF processing has been proposed as a promising approach. However, this approach increases the number of physical nodes in the chains, and thus decreases the reliability, which is also critical for Tactile Internet applications. Furthermore, the cost depends upon the specific VNF placement and traffic routing, as nodes and links are heterogeneous. This article tackles the issues of reliability and cost when embedding delay-constrained slices. We model the problem as an optimization problem that minimizes reliability degradation and cost while ensuring the strict delay constraint when a parallel VNF processing approach is used. Due to the complexity of the formulated problem, we also propose a Tabu search-based algorithm to find sub-optimal solutions. The results indicate that our proposed algorithm can significantly improve cost and reliability while meeting a strict delay constraint

A Case Study on the Deployment of a Tactile Internet Application in a Hybrid Cloud, Edge, and Mobile Ad Hoc Cloud Environment

The tactile Internet is the next step after the Internet of Things (IoT). It enables the steering and control of virtual and real objects through the Internet and requires a very low round trip latency. This article is devoted to a case study on the deployment of a tactile Internet application in a hybrid cloud, edge, and mobile ad hoc cloud environment. We deploy a remote phobia-treatment application as a set of components. Remote phobia treatment allows phobia patients to have therapy sessions under the guidance of an expert therapist located remotely, with patients and therapist sharing the same virtual reality (VR) environment. A three-layer architecture (cloud, edge, and mobile ad hoc cloud) is proposed for the deployment. A prototype is built with Microsoft Azure at the cloud layer, laptops at the edge layer, and smartphones at the mobile ad hoc cloud layer. End-users are equipped with an HTC VIVE headset for VR rendering and Gloveone gloves for haptic sensations rendering. Extensive performance measurements are made by varying the component deployment patterns as well as the distance between the therapist and patient. Our results demonstrate clearly that the addition of mobile ad hoc cloud to the edge and cloud does bring added value in terms of latency reduction when deploying tactile Internet applications