Which of the following is not a part of an E2E Network Slice?

An End-to-End (E2E) network slice is a complete logical network that provides specific capabilities and characteristics. This E2E slice is constructed from three distinct and standardized segments or sub-slices: the Access Slice (covering the Radio Access Network - RAN), the Transport Slice (providing connectivity between RAN and Core), and the Core Slice (covering the 5G Core network). These three components are orchestrated together to deliver the required service level agreement (SLA). The term "Cloud Slice" is not a standard segment in the E2E network slicing architecture. While network functions within the primary slices are often cloud-native and deployed on cloud infrastructure, "Cloud Slice" is not a formal architectural component itself.

B. Core Slice: This is an essential segment of an E2E slice, containing the necessary 5G Core (5GC) network functions like AMF, SMF, and UPF.
C. Access Slice: This is an essential segment of an E2E slice, comprising the Radio Access Network (RAN) resources and functions needed to connect user equipment.
D. Transport Slice: This is an essential segment of an E2E slice, responsible for providing the required connectivity and resources between the access and core network segments.

1. Nokia. (2020). 5G network slicing: A business-driven network architecture. White Paper. Page 5, Figure 2 and the section "End-to-end network slicing," which states, "An end-to-end slice consists of a RAN slice part, a transport slice part and a core slice part."

2. 3GPP. (2022). TS 23.501: System architecture for the 5G System (5GS); Stage 2 (Release 17). V17.5.0. Section 5.15.1, "General concepts for Network Slicing," describes a Network Slice Instance (NSI) as being composed of network functions and resources from the RAN, Core Network (CN), and the transport network.

3. Afolabi, I., Taleb, T., Samdanis, K., Ksentini, A., & Flinck, H. (2018). Network Slicing and Softwarization: A Survey on Principles, Enabling Technologies, and Solutions. IEEE Communications Surveys & Tutorials, 20(3), 2429-2453. https://doi.org/10.1109/COMST.2018.2815638. In Section III.A, "Network Slice Segments," the paper explicitly identifies the three main segments of an E2E slice as the Radio Access Network (RAN), the Core Network (CN), and the Transport Network (TN).