2.3 Given a scenario, select and configure wireless devices and technologies
Network Types
📘CompTIA Network+ (N10-009)
Infrastructure Wireless Networks
An infrastructure wireless network is one of the two main types of Wi-Fi networks, the other being ad hoc. In infrastructure mode, all wireless devices communicate through a central device, typically called an Access Point (AP).
Think of it as a “hub-and-spoke” network: all devices (clients) connect to the hub (AP), and the AP manages communication, security, and connectivity to the rest of the network.
Key Components
- Access Point (AP)
- Acts as a central hub or gateway for wireless devices.
- Connects wireless clients to the wired network (LAN) or the internet.
- Examples of AP features important for the exam:
- SSID broadcast: The AP advertises the network name.
- Security protocols: WPA3, WPA2, etc.
- Channel management: Avoid interference with other APs.
- Wireless Clients
- Devices like laptops, desktops with Wi-Fi cards, printers, or IP phones that connect to the AP.
- Clients do not communicate directly with each other; they send all traffic through the AP.
- Wireless Controller (Optional)
- In larger enterprise networks, multiple APs are managed by a wireless controller.
- Handles configuration, security policies, and load balancing between APs.
How Communication Works
- A wireless client sends data to the AP.
- The AP forwards data either to:
- Another wireless client on the same network.
- A wired network (LAN) device or server.
- The internet via the router.
- All devices rely on the AP for proper routing, security checks, and network management.
Key Features for the Exam
- Centralized Management
- APs control access, authentication, and traffic flow.
- Makes it easier to enforce security policies.
- Extended Network Coverage
- Multiple APs can be deployed in a building.
- Each AP connects back to the central network, forming a Basic Service Set (BSS).
- When multiple APs are connected with the same SSID, it’s called an Extended Service Set (ESS).
- Security
- Infrastructure networks support enterprise-grade security.
- Authentication methods:
- WPA2/WPA3 Personal: For smaller networks, password-based.
- WPA2/WPA3 Enterprise: For corporate networks, uses RADIUS server for user authentication.
- Roaming
- Clients can move between APs without losing connectivity.
- APs and controllers coordinate so the client stays connected smoothly.
Infrastructure vs Ad Hoc
| Feature | Infrastructure | Ad Hoc |
|---|---|---|
| Central Device | Yes, AP | No, devices connect directly |
| Scalability | High, multiple APs | Limited, usually small networks |
| Security | Strong, centralized | Weak, peer-to-peer only |
| Roaming | Supported | Not supported |
| Common Use | Enterprise & office Wi-Fi | Temporary peer-to-peer connections |
Why This Matters for the Exam
- Infrastructure mode is the default for enterprise networks.
- You should recognize:
- AP as the central device.
- Client devices communicate through the AP, not directly.
- Roaming, security, and coverage are managed centrally.
- Questions may ask you to choose the correct network type for a scenario:
- If multiple users need controlled access to a network, pick infrastructure.
- If devices connect temporarily without an AP, pick ad hoc.
Summary
- Infrastructure wireless network = Centralized Wi-Fi network.
- AP = Hub that connects wireless clients to LAN or internet.
- Supports security, roaming, scalability, and management.
- Enterprise Wi-Fi networks almost always use infrastructure mode.
