Function-as-a-Service (FaaS) allows developers to define, orchestrate and run modular event-based pieces of code on virtualised resources, without the burden of managing the underlying infrastructure nor the life-cycle of such pieces of code. Indeed, FaaS providers offer resource auto-provisioning, auto-scaling and pay-per-use billing at no costs for idle time. This makes it easy to scale running code and it represents an effective and increasingly adopted way to deliver software. This article aims at offering an overview of the existing literature in the field of next-gen FaaS from three different perspectives: (i) the definition of FaaS orchestrations, (ii) the execution of FaaS orchestrations in Fog computing environments, and (iii) the security of FaaS orchestrations. Our analysis identify trends and gaps in the literature, paving the way to further research on securing FaaS orchestrations in Fog computing landscapes.

功能即服务（FaaS）允许开发人员在虚拟化资源上定义，编排和运行基于模块的基于事件的代码段，而无需管理基础架构的负担或此类代码段的生命周期。确实，FaaS提供商免费提供资源自动配置，自动扩展和按使用付费计费，而无需花费任何空闲时间。这使得扩展正在运行的代码变得容易，并且它代表了一种有效且日益被采用的交付软件的方式。本文旨在从三个不同的角度概述下一代FaaS领域的现有文献：（i）FaaS编排的定义，（ii）在Fog计算环境中执行FaaS编排，以及（iii）该安全FaaS业务流程。我们的分析确定了文献中的趋势和差距，为进一步研究在雾计算环境中确保FaaS编排铺平了道路。