Network slicing will permit offering to vertical customers tailored end-to-end logical networks in an on-demand fashion, on top of a common telecom infrastructure, achieving a Slices-as-a-Service (SlaaS) business model. This is possible due to the progressive introduction of network softwarization techniques, such as programmability and virtualization, into existing operational networks, enabling dynamic and flexible provision of slices. Those vertical customers could require the control not only of the network functions composing the end-to-end service, but also of the connectivity among them, e.g., for influencing the paths for steering traffic among function instances. However, this can be problematic since decisions from one vertical customer can collide with decisions from others. One aspect not yet sufficiently investigated is how to permit vertical customers to jointly control the service functions and the underlay connectivity, in such a way that could operate the allocated slice as if it was actually a dedicated network entirely for them. This paper explores some architectural proposition in this respect illustrated with some potential use cases and it provides an example of the provision of SlaaS for a vertical customer.

网络切片将允许在通用电信基础架构之上按需提供按需方式为垂直客户量身定制的端到端逻辑网络，从而实现切片即服务（SlaaS）业务模型。由于将网络软化技术（例如可编程性和虚拟化）逐步引入到现有的运营网络中，从而能够动态，灵活地提供分片，因此这是可能的。这些垂直客户可能不仅需要控制组成端到端服务的网络功能，还需要控制它们之间的连接性，例如，以影响功能实例之间的流量控制路径。但是，这可能会带来问题，因为一个垂直客户的决策可能会与其他垂直客户的决策发生冲突。尚未充分研究的一个方面是如何允许垂直客户以这样一种方式共同控制服务功能和底层连接，即可以操作所分配的片，就好像它实际上是完全为他们服务的专用网络一样。本文探讨了这方面的一些架构主张，并举例说明了一些潜在的用例，并提供了为垂直客户提供SlaaS的示例。