The network slicing concept in 5G is not new, as this builds on the LTE concept (built on 3G..) of wireless access prioritization.
Since wireless spectrum is a precious resource, maximizing the usage and catering to various needs of the applications dictates that wireless access be segmented for different use cases.
For example, if a user is watching a video stream, little buffering will not impact user experience, user can be given bandwidths with some smaller gaps. However, voice calls cannot have gaps.
5G Network slicing takes this concept further by combining the remaining network elements, thus enabling end-to-end network slicing. Slicing allows services to differentiate from each other by leveraging total network experience. For example, a private Network slice adds network separation (VPN-like) as the key offering. Similarly, mission-critical services such as MCPTT leverages network slicing to prioritize traffic across all the network segments such as wireless access, transport, and core networks.