Examkin

Question

Difficulty: MediumNetwork Components Roles and Functions

An enterprise network engineer is implementing a centralized wireless network architecture utilizing Cisco Lightweight Access Points (LAPs) and a centralized Wireless LAN Controller (WLC) operating in Split-MAC mode. Which operational responsibility is handled directly by the Wireless LAN Controller rather than being processed locally by the Lightweight Access Point?

  1. A
    Transmitting 802.11 beacon frames and handling real-time probe responses for nearby wireless clients
  2. Processing 802.1X client authentication requests and managing centralized wireless client associationsAnswer
  3. C
    Encrypting and decrypting 802.11 frame payloads in real time for connected wireless endpoints
  4. D
    Generating local Layer 2 discovery advertisements to advertise link status over LLDP to the access switch

Answer

Processing 802.1X client authentication requests and managing centralized wireless client associations
In Cisco Split-MAC wireless architecture, the Wireless LAN Controller (WLC) is responsible for centralizing management and control plane operations. This includes processing 802.1X client authentication, managing client association states, enforcing security policies, and orchestrating Radio Resource Management (RRM). Real-time operations, such as beaconing, probe responses, and frame encryption, remain on the Lightweight Access Point (LAP).

Step-by-Step Solution

1
Analyze the Split-MAC architecture responsibilities between Lightweight Access Points (LAPs) and Wireless LAN Controllers (WLCs).
Split-MAC divides 802.11 protocol handling into real-time MAC tasks (handled by the LAP) and non-real-time management tasks (handled by the WLC).
This division optimizes latency-sensitive frame transmissions while keeping network-wide security and RF policy control centralized.
2
Identify real-time functions assigned to the LAP.
Real-time duties include beacon transmission, probe responses, packet acknowledgments (ACKs), and 802.11 frame encryption/decryption.
These tasks require microsecond-level timing and must occur directly at the physical radio interface.
3
Identify non-real-time functions assigned to the WLC.
Non-real-time duties include 802.1X security authentication processing, client association tracking, roaming coordination, and Radio Resource Management (RRM).
Centralizing these tasks allows the WLC to maintain consistent security policies and system-wide visibility across all access points.

Key Concept

Split-MAC Architecture and WLC vs. LAP Functional Roles
Rate this question

Topics

Network Components Roles and Functions

More questions from this topic