Service Function Chaining (SFC) is a trending paradigm, which has helped to introduce unseen flexibility in telecom networks. Network service providers, as well as big network infrastructure providers, are competing to offer personalized services for their customers. Hence, added value services require the invocation of various elementary functions called Service Functions (SFs). The SFC concept composes and imposes the order in which SFs are invoked for a particular service. Emerging technologies such as Software Defined Networking and Network Function Virtualization support the dynamic creation and management of SFC. Even though SFC is an active technical area where several aspects were already standardized and many SFC architecture flavors are currently deployed, yet some challenges and open issues are still to be solved. In this paper, we present different research problems related to SFC and investigate several key challenges that should be addressed to realize more reliable SFC operations.

翻译：服务功能链是一个趋势模式,有助于在电信网络中引入无形的灵活性,网络服务提供商和大型网络基础设施供应商正在竞争,为其客户提供个性化服务,因此,增值服务需要援引被称为服务功能的各种基本职能。SFC概念构成并规定了为特定服务援引SFC的顺序。软件定义网络和网络功能虚拟化等新兴技术支持SFC的动态创建和管理。即使SFC是一个活跃的技术领域,其中若干方面已经标准化,许多SFC结构口味已经部署,但一些挑战和开放的问题仍有待解决。在本文件中,我们提出了与SFC有关的不同研究问题,并研究了为实现更可靠的SFC业务而应应对的若干关键挑战。