Cozy Bean Café

Wireless network blueprint  ·  Assignment 5 — Securing a Small Wi-Fi Deployment

26 April 2026

Coverage
MENU $ $ ↑ ISP OPEN 1 2 3 4 5 CALLOUTS 1 AP-1 “Brew” Wi-Fi 6 · 2.4 / 5 GHz · ceiling. ch 6 (2.4) · ch 36 (5) 2 AP-2 “Bean” Wi-Fi 6 · ch 11 (2.4) · ch 149 (5) Non-overlapping with AP-1. 3 Coverage overlap ~25% intentional overlap for seamless roaming (802.11k/v/r). 4 Guest VLAN boundary Dashed line separates customer zone from counter / staff. 5 Uplink Router → ISP at counter. Gigabit fiber, WAN-side firewall. LEGEND Guest coverage (VLAN 20) Staff (VLAN 10)
Card A

Hardware

  • Ubiquiti U6-Lite (Wi-Fi 6, 2×2 MU-MIMO) or equivalent
  • UniFi Dream Router or Mikrotik hAP ax² (gateway + controller)
  • +PoE switch with 4× PoE+ ports
Card B

Security

  • WPA3-Personal (SAE) primary
  • WPA3 Transition Mode for legacy devices
  • PMF (Protected Management Frames) required
  • WPS, UPnP, remote admin all disabled
  • 2.4 GHz channel plan: 1/6/11 spacing (we use 6 + 11)
Card C

Networks

SSIDBandVLANAuthIsolation
CozyBean-Guest2.4 + 520WPA3-SAE + captive portalClient + AP
CozyBean-Ops (hidden)5 only10WPA3-SAE, MAC allowlistNone (intra-VLAN OK)
Card D

Operational policies

  1. Guest client isolation (no peer-to-peer discovery)
  2. VLAN 10 ↔ VLAN 20 firewall: deny all
  3. Per-client cap: 5 Mbps down / 2 Mbps up on guest
  4. Session timeout: 120 min, then re-auth via captive portal
  5. Captive portal: ToS + optional email opt-in (GDPR-compliant)
  6. Auto firmware updates: weekly check, security patches auto-applied
  7. Admin: 16+ char passphrase, TOTP 2FA, no default creds
  8. Quarterly staff PSK rotation; immediate on offboarding
  9. Connection logs retained 30 days (incident response only)
  10. Monthly RF scan for rogue APs / evil twins

Pitfalls to watch

2.4 GHz interferenceMicrowaves, Bluetooth speakers, neighbor APs all share the band.
Pre-2019 devices without WPA3Handled by WPA3 Transition Mode — no SAE downgrade attack surface.
Outdoor seating gapOptional 3rd AP in window, or accept as out-of-scope.
Firmware driftAuto-update mitigates; quarterly audit confirms.
Staff sharing guest passwordSeparate SSID + onboarding training; rotate quarterly.
Captive portal fatigue“Remember device for 7 days” cookie keeps regulars happy.