What security service allows an administrator to assign service levels to a specific user in an enterprise wireless gateway?

Class of Service (CoS) is the correct answer because it refers to a network feature that allows administrators to prioritize network traffic and assign specific service levels to different users or types of traffic within an enterprise wireless gateway. By utilizing CoS, an administrator can manage bandwidth allocation, ensure that critical applications receive the necessary resources for uninterrupted service, and enhance overall user experience based on predefined policies. This capability is essential in environments where multiple users may share bandwidth and where varying levels of service quality are necessary for different types of applications or user roles.

Traffic shaping primarily focuses on controlling the flow of data into and out of a network to prevent congestion and ensure that bandwidth is used efficiently but does not provide granular service level assignments to specific users. Network Access Control (NAC) involves managing user access to networked resources, focusing more on security and compliance rather than the level of service provided to users. End-to-End Encryption (E2EE) is aimed at securing data during transmission and does not relate to the assignment of service levels. Thus, Class of Service is the most relevant choice for assigning different service levels to users in a wireless network.