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Module 55
Troubleshooting Wireless Issues
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# 📘 CCNA 200-301 - Video 55: Troubleshooting Wireless Issues ## Deep Study Notes --- ## 📌 Learning Objectives By the end of this video, you should understand: - Common wireless issues and their causes - Wireless client connectivity troubleshooting - AP registration and CAPWAP issues - RF interference and coverage problems - Wireless security issues (authentication, encryption) - Roaming issues - Wireless troubleshooting tools and commands --- ## 🧠 Core Concepts ### 1. Common Wireless Issues Overview ``` ┌─────────────────────────────────────────────────────────────────────────────┐ │ COMMON WIRELESS ISSUES │ ├─────────────────────────────────────────────────────────────────────────────┤ │ │ │ CLIENT CONNECTIVITY ISSUES: │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ • Client cannot see SSID │ │ │ │ • Client cannot associate │ │ │ │ • Client cannot authenticate │ │ │ │ • Client cannot get IP address │ │ │ │ • Intermittent connectivity │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ │ AP ISSUES: │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ • AP not joining controller │ │ │ │ • AP stuck in "downloading" state │ │ │ │ • AP in "standalone" mode │ │ │ │ • AP power issues │ │ │ │ • AP coverage gaps │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ │ RF ISSUES: │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ • Interference (Wi-Fi, non-Wi-Fi) │ │ │ │ • Co-channel interference (CCI) │ │ │ │ • Adjacent channel interference (ACI) │ │ │ │ • Low signal strength │ │ │ │ • High noise floor │ │ │ │ • Coverage holes │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ │ SECURITY ISSUES: │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ • Authentication failures (PSK, 802.1X) │ │ │ │ • RADIUS server unreachable │ │ │ │ • Certificate issues │ │ │ │ • Rogue AP detection │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ │ ROAMING ISSUES: │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ • Client sticks to distant AP │ │ │ │ • Roaming delay │ │ │ │ • Dropped sessions during roam │ │ │ │ • Coverage overlap issues │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ └─────────────────────────────────────────────────────────────────────────────┘ ``` --- ### 2. Wireless Client Troubleshooting **Client Connectivity Flow:** ``` ┌─────────────────────────────────────────────────────────────────────────────┐ │ CLIENT CONNECTIVITY FLOW │ ├─────────────────────────────────────────────────────────────────────────────┤ │ │ │ 1. SCAN │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ • Client scans for available SSIDs │ │ │ │ • Passive scanning (listening for beacons) │ │ │ │ • Active scanning (sending probes) │ │ │ │ If SSID not visible → Check AP, SSID broadcast │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ │ │ ▼ │ │ 2. ASSOCIATION │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ • Client sends Association Request │ │ │ │ • AP sends Association Response │ │ │ │ If association fails → Check AP capacity, MAC filtering │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ │ │ ▼ │ │ 3. AUTHENTICATION │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ • 802.11 authentication (Open/Shared) │ │ │ │ • 802.1X/EAP (if using WPA2-Enterprise) │ │ │ │ • PSK validation (if using WPA2-Personal) │ │ │ │ If authentication fails → Check credentials, RADIUS server │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ │ │ ▼ │ │ 4. IP ADDRESS ASSIGNMENT │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ • DHCP request │ │ │ │ • IP address assigned │ │ │ │ If no IP → Check DHCP server, VLAN, relay │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ │ │ ▼ │ │ 5. NETWORK ACCESS │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ • Client can ping gateway │ │ │ │ • Client can access resources │ │ │ │ If no access → Check VLAN, ACLs, firewall │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ └─────────────────────────────────────────────────────────────────────────────┘ ``` **Client Troubleshooting Commands (WLC):** ```cisco ! Display connected clients WLC# show client summary Client MAC AP Name WLAN ID VLAN ID IP Address State aa:bb:cc:dd:ee:ff AP-01 1 10 192.168.1.50 Associated aa:bb:cc:dd:ee:fe AP-02 2 20 192.168.2.100 Associated ! Display detailed client information WLC# show client detail aa:bb:cc:dd:ee:ff Client MAC Address: aa:bb:cc:dd:ee:ff Client IPv4 Address: 192.168.1.50 Client IPv6 Address: fe80::aabb:ccff:fedd:eeff Client Username: jdoe AP Name: AP-01 AP MAC Address: 00:1a:2b:3c:4d:5e WLAN ID: 1 WLAN Profile: Corporate Interface: vlan10 State: Associated Policy Manager State: RUN Authentication Algorithm: Open System Central Assoc: Yes Central Auth: Yes Mobility Role: Local Mobility Move Count: 0 Mobile Anchor: 192.168.1.100 Session Timeout: 86400 Idle Timeout: 300 Data Rate Set: 6,9,12,18,24,36,48,54 Supported Rates: 6,9,12,18,24,36,48,54 802.11n Capable: Yes 802.11ac Capable: Yes RSSI: -45 dBm SNR: 45 dB Signal Strength: Excellent Client Type: WPA2-Enterprise Encryption Cipher: AES-CCMP ``` **Windows Client Troubleshooting:** ```cmd ! Display wireless interfaces netsh wlan show interfaces ! Display wireless networks netsh wlan show networks ! Display wireless profiles netsh wlan show profiles ! Delete wireless profile netsh wlan delete profile name="Corporate-WiFi" ! Generate wireless report netsh wlan show wlanreport ``` **macOS Client Troubleshooting:** ```bash # Display wireless interface ifconfig # or ipconfig getifaddr en0 # Scan for networks (macOS) airport -s # Display wireless diagnostics /System/Library/CoreServices/Wireless\ Diagnostics.app ``` --- ### 3. AP Registration Troubleshooting (CAPWAP) **AP Join Process:** ``` ┌─────────────────────────────────────────────────────────────────────────────┐ │ AP JOIN PROCESS │ ├─────────────────────────────────────────────────────────────────────────────┤ │ │ │ AP WLC │ │ │ │ │ 1. AP discovers WLC │ │ │ (DHCP Option 43, DNS, broadcast) │ │ │ ─────────────────────────────────────────────────────────────► │ │ │ │ │ │ 2. AP sends Join Request │ │ │ ─────────────────────────────────────────────────────────────► │ │ │ │ │ │ 3. WLC sends Join Response │ │ │ ◄───────────────────────────────────────────────────────────── │ │ │ │ │ │ 4. DTLS tunnel established │ │ │ ◄─────────────────────────────────────────────────────────────► │ │ │ │ │ │ 5. AP downloads configuration │ │ │ ◄───────────────────────────────────────────────────────────── │ │ │ │ │ │ 6. AP enters "Registered" state │ │ │ │ └─────────────────────────────────────────────────────────────────────────────┘ ``` **AP Discovery Methods:** | Method | Description | |--------|-------------| | **DHCP Option 43** | DHCP server provides WLC IP address | | **DNS** | AP resolves CISCO-CAPWAP-CONTROLLER.localdomain | | **Broadcast** | AP broadcasts discovery request | | **Locally Configured** | AP has static WLC IP address | **AP Troubleshooting Commands:** ```cisco ! Display AP summary WLC# show ap summary AP Name Slots AP Model Eth MAC Location Country IP Address State AP-01 2 2800 aa:bb:cc:dd:ee:ff default US 192.168.1.102 Registered AP-02 2 2800 aa:bb:cc:dd:ee:fe default US 192.168.1.103 Registered AP-03 2 2800 aa:bb:cc:dd:ee:fd default US 192.168.1.104 Downloading ! Display AP join statistics WLC# show ap join statistics summary AP Name Last Join Time Last Join Status Join Attempts AP-01 10:30:45 Successful 1 AP-02 10:31:23 Successful 1 AP-03 10:32:01 Failed: Join Timer Expired 3 ! Debug AP join WLC# debug capwap events enable WLC# debug capwap errors enable ! Check AP join failure reasons WLC# show ap join stats summary WLC# show ap join stats detailed <AP-MAC> ``` **Common AP Issues:** | Issue | Symptom | Solution | |-------|---------|----------| | **AP not joining** | AP stuck in "Downloading" | Check DHCP, WLC reachability, certificates | | **AP stuck in "Discovering"** | No WLC found | Verify DHCP Option 43, DNS, connectivity | | **Certificate errors** | DTLS handshake fails | Check AP and WLC certificates, time sync | | **Image mismatch** | AP downloading image | Ensure AP image available on WLC | | **AP in "Standalone" mode** | AP not joining controller | Check AP mode, convert to lightweight | --- ### 4. RF Interference and Coverage Issues **RF Metrics:** | Metric | Description | Target | |--------|-------------|--------| | **RSSI** | Received Signal Strength Indicator | > -67 dBm (good), < -70 dBm (poor) | | **SNR** | Signal-to-Noise Ratio | > 25 dB (good), < 20 dB (poor) | | **Noise Floor** | Background RF noise | < -90 dBm (good) | | **Channel Utilization** | How busy the channel is | < 50% (good) | ``` ┌─────────────────────────────────────────────────────────────────────────────┐ │ RF INTERFERENCE TYPES │ ├─────────────────────────────────────────────────────────────────────────────┤ │ │ │ CO-CHANNEL INTERFERENCE (CCI): │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ • Multiple APs on same channel │ │ │ │ • Causes contention and retries │ │ │ │ • Solution: Proper channel planning │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ │ ADJACENT CHANNEL INTERFERENCE (ACI): │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ • Overlapping channels (e.g., channels 1 and 2) │ │ │ │ • Causes packet corruption │ │ │ │ • Solution: Use non-overlapping channels (1,6,11) │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ │ NON-Wi-Fi INTERFERENCE: │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ • Bluetooth, microwaves, cordless phones, baby monitors │ │ │ │ • Causes packet loss and retries │ │ │ │ • Solution: Identify source, use 5 GHz band │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ └─────────────────────────────────────────────────────────────────────────────┘ ``` **RF Troubleshooting Commands (WLC):** ```cisco ! Display RF summary WLC# show ap rf-summary AP Name Radio Channel Tx Power Clients Channel Util Noise SNR AP-01 Radio0 1 8 12 35% -92 45 AP-01 Radio1 36 7 8 15% -95 48 AP-02 Radio0 6 8 8 42% -90 40 AP-02 Radio1 40 7 15 18% -94 45 ! Display interference detection WLC# show ap 802.11a interference-detection WLC# show ap 802.11b interference-detection ! Display RRM (Radio Resource Management) status WLC# show advanced 802.11a rrm summary WLC# show advanced 802.11b rrm summary ``` **RF Troubleshooting Commands (AP Console):** ```cisco ! Check RF environment from AP AP# show controllers dot11Radio 0 AP# show controllers dot11Radio 1 ! Display nearby APs AP# show ap auto-rf dot11 0 AP# show ap auto-rf dot11 1 ``` --- ### 5. Wireless Security Troubleshooting **Common Authentication Issues:** | Issue | Symptom | Solution | |-------|---------|----------| | **PSK mismatch** | Client fails to authenticate | Verify passphrase on client and AP | | **RADIUS server unreachable** | 802.1X authentication times out | Check RADIUS server connectivity, shared secret | | **Certificate issues** | EAP-TLS/PEAP fails | Verify certificate validity, chain | | **Client not in RADIUS database** | Authentication fails | Add client to RADIUS database | | **Wrong EAP type** | Authentication fails | Configure correct EAP method on client | **RADIUS Troubleshooting:** ```cisco ! Check RADIUS server status (WLC) WLC# show radius summary VLAN ID Server Address Port Auth Status Acct Status 1 192.168.1.100 1812 Up Up ! Debug RADIUS (WLC) WLC# debug aaa radius enable WLC# debug aaa authentication enable ! Test RADIUS connectivity WLC# test aaa radius -server 192.168.1.100 user test pass test123 ``` **Security Configuration Verification:** ```cisco ! Display WLAN security settings WLC# show wlan 1 WLAN Profile Name: Corporate WLAN ID: 1 SSID: Corp-WiFi Status: Enabled Security: WPA2-Enterprise Authentication: 802.1X Encryption: AES-CCMP RADIUS Servers: Server1: 192.168.1.100 (Active) Server2: 192.168.1.101 (Standby) ``` --- ### 6. Roaming Troubleshooting **Roaming Types:** | Roaming Type | Description | Latency | |--------------|-------------|---------| | **Layer 2 Roaming** | Same subnet, different AP | < 10 ms | | **Layer 3 Roaming** | Different subnet | < 50 ms | | **Fast Roaming (802.11r)** | Fast transition between APs | < 10 ms | ``` ┌─────────────────────────────────────────────────────────────────────────────┐ │ ROAMING ISSUES │ ├─────────────────────────────────────────────────────────────────────────────┤ │ │ │ STICKY CLIENT: │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ • Client stays connected to distant AP │ │ │ │ • Poor performance │ │ │ │ • Solution: Adjust RSSI thresholds, enable band steering │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ │ ROAMING DELAY: │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ • Long pause during roam │ │ │ │ • Voice/video disruption │ │ │ │ • Solution: Enable 802.11r (Fast Roaming) │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ │ COVERAGE GAPS: │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ • No AP available in area │ │ │ │ • Client disconnects │ │ │ │ • Solution: Add AP, adjust power │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ │ INSUFFICIENT OVERLAP: │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ • Roaming not possible │ │ │ │ • Client drops connection │ │ │ │ • Solution: Add APs or increase power │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ └─────────────────────────────────────────────────────────────────────────────┘ ``` **Roaming Troubleshooting:** ```cisco ! Display client roam history (WLC) WLC# show client roam-history <client-mac> Client MAC: aa:bb:cc:dd:ee:ff Roam Count: 5 Roam Time From AP To AP Type Reason 10:30:45 AP-01 AP-02 L2 Better RSSI 10:32:12 AP-02 AP-03 L2 Better RSSI 10:35:23 AP-03 AP-01 L2 Better RSSI ! Display client statistics WLC# show client stats <client-mac> ``` --- ### 7. Wireless Troubleshooting Tools | Tool | Purpose | Use Case | |------|---------|----------| | **Spectrum Analyzer** | Identify RF interference | Find non-Wi-Fi interference | | **Wi-Fi Analyzer** | View APs, channels, signal strength | Site survey, channel planning | | **Wireshark** | Packet capture | Analyze 802.11 frames, authentication | | **WLC CLI** | AP and client status | Monitor connectivity | | **AP Console** | AP-level debugging | AP registration issues | | **Client Tools** | Client-side diagnostics | Authentication, connectivity | ``` ┌─────────────────────────────────────────────────────────────────────────────┐ │ WIRELESS TROUBLESHOOTING FLOW │ ├─────────────────────────────────────────────────────────────────────────────┤ │ │ │ START: Client cannot connect │ │ │ │ │ ▼ │ │ Can client see SSID? │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ If NO → Check AP, SSID broadcast, client drivers │ │ │ │ If YES → Continue │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ │ │ ▼ │ │ Can client associate? │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ If NO → Check AP capacity, MAC filtering, client limit │ │ │ │ If YES → Continue │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ │ │ ▼ │ │ Can client authenticate? │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ If NO → Check PSK, RADIUS server, certificates │ │ │ │ If YES → Continue │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ │ │ ▼ │ │ Does client get IP address? │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ If NO → Check DHCP server, VLAN, relay │ │ │ │ If YES → Continue │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ │ │ ▼ │ │ Check signal strength │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ • RSSI > -67 dBm? │ │ │ │ • SNR > 25 dB? │ │ │ │ If NO → Check AP placement, interference │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ │ │ ▼ │ │ PROBLEM SOLVED │ │ │ └─────────────────────────────────────────────────────────────────────────────┘ ``` --- ## 🔧 Complete Configuration Examples ### Lab 1: AP Registration Troubleshooting ```cisco ! Step 1: Check AP summary show ap summary ! Step 2: Check AP join statistics show ap join statistics summary ! Step 3: Check DHCP for AP show dhcp leases ! Step 4: Debug AP join debug capwap events enable debug capwap errors enable ! Step 5: Check AP console show controllers show inventory show running-config ``` --- ### Lab 2: Client Connectivity Troubleshooting ```cisco ! Step 1: Check client summary show client summary ! Step 2: Check client details show client detail <client-mac> ! Step 3: Check client statistics show client stats <client-mac> ! Step 4: Debug client debug client <client-mac> ``` --- ### Lab 3: RF Troubleshooting ```cisco ! Step 1: Check RF summary show ap rf-summary ! Step 2: Check interference show ap 802.11a interference-detection show ap 802.11b interference-detection ! Step 3: Check RRM show advanced 802.11a rrm summary show advanced 802.11b rrm summary ! Step 4: Check channel utilization show ap auto-rf dot11 0 show ap auto-rf dot11 1 ``` --- ## ✅ Exam Tips (For CCNA 200-301) | Topic | What Cisco Tests | |-------|------------------| | **Client Connectivity** | Scan, associate, authenticate, IP assignment | | **AP Registration** | CAPWAP discovery, DHCP Option 43, DNS | | **RF Metrics** | RSSI, SNR, noise, channel utilization | | **Interference** | Co-channel, adjacent channel, non-Wi-Fi | | **Roaming** | Layer 2, Layer 3, fast roaming (802.11r) | | **Security** | PSK, 802.1X, RADIUS | ### Common Exam Scenarios: **Scenario 1:** "A client can see the SSID but cannot associate. What is the most likely issue?" - **Answer:** AP capacity full, MAC filtering, or client limit reached **Scenario 2:** "AP is stuck in 'Downloading' state and not joining WLC. What is the most likely issue?" - **Answer:** Image mismatch, AP cannot download image from WLC **Scenario 3:** "Clients experience poor performance on channel 1. What could be the issue?" - **Answer:** Co-channel interference from other APs on same channel --- ## 📝 Summary (1-Minute Revision) ``` WIRELESS TROUBLESHOOTING: CLIENT CONNECTIVITY: ├── Scan: SSID visible? ├── Associate: AP capacity, MAC filter ├── Authenticate: PSK, 802.1X, RADIUS ├── IP Address: DHCP, VLAN └── Network Access: VLAN, ACLs AP REGISTRATION: ├── Discovery: DHCP Option 43, DNS, broadcast ├── Join Request/Response ├── DTLS tunnel ├── Configuration download └── State: Registered, Downloading, Standalone RF METRICS: ├── RSSI: > -67 dBm (good) ├── SNR: > 25 dB (good) ├── Noise: < -90 dBm (good) └── Channel Utilization: < 50% (good) INTERFERENCE: ├── Co-channel: Same channel (use 1,6,11) ├── Adjacent channel: Overlapping channels └── Non-Wi-Fi: Bluetooth, microwave, cordless ROAMING: ├── Layer 2: Same subnet ├── Layer 3: Different subnet ├── Fast roaming: 802.11r └── Sticky client: Client sticks to distant AP VERIFICATION COMMANDS: ├── show client summary ├── show client detail ├── show ap summary ├── show ap rf-summary ├── show radius summary └── debug client ``` --- ## 🧪 Practice Questions **1. What is the recommended minimum RSSI for good wireless connectivity?** - A) -50 dBm - B) -67 dBm - C) -70 dBm - D) -80 dBm <details> <summary>Answer</summary> <b>B) -67 dBm</b> - RSSI above -67 dBm is considered good. </details> **2. Which CAPWAP discovery method uses DHCP Option 43?** - A) DNS - B) Broadcast - C) DHCP - D) Static <details> <summary>Answer</summary> <b>C) DHCP</b> - DHCP Option 43 provides WLC IP address to APs. </details> **3. What does SNR stand for?** - A) Signal-to-Noise Ratio - B) Signal-to-Noise Response - C) Signal Noise Ratio - D) Signal Noise Response <details> <summary>Answer</summary> <b>A) Signal-to-Noise Ratio</b> - Measures signal strength relative to background noise. </details> **4. Which wireless issue occurs when multiple APs use the same channel?** - A) Adjacent channel interference - B) Co-channel interference - C) Non-Wi-Fi interference - D) Coverage hole <details> <summary>Answer</summary> <b>B) Co-channel interference</b> - Multiple APs on same channel cause contention. </details> **5. What is the recommended non-overlapping channels for 2.4 GHz?** - A) 1, 5, 9 - B) 1, 6, 11 - C) 2, 7, 12 - D) 3, 8, 13 <details> <summary>Answer</summary> <b>B) 1, 6, 11</b> - These are the only non-overlapping channels in 2.4 GHz. </details> **6. Which command displays connected wireless clients on a WLC?** - A) `show client summary` - B) `show wireless clients` - C) `show clients` - D) `show station` <details> <summary>Answer</summary> <b>A) `show client summary`</b> - Displays summary of connected clients. </details> **7. What is the primary purpose of 802.11r?** - A) Increased bandwidth - B) Fast roaming - C) Better security - D) Backward compatibility <details> <summary>Answer</summary> <b>B) Fast roaming</b> - 802.11r enables fast transition between APs. </details> **8. A client can associate but cannot get an IP address. What should be checked?** - A) PSK - B) DHCP server - C) AP power - D) Channel <details> <summary>Answer</summary> <b>B) DHCP server</b> - No IP address indicates DHCP issue. </details> **9. Which tool is best for identifying non-Wi-Fi interference?** - A) Wi-Fi analyzer - B) Spectrum analyzer - C) Wireshark - D) WLC CLI <details> <summary>Answer</summary> <b>B) Spectrum analyzer</b> - Identifies non-Wi-Fi RF interference sources. </details> **10. What does a "sticky client" refer to?** - A) Client with strong signal - B) Client stuck to distant AP - C) Client with authentication issues - D) Client with no IP address <details> <summary>Answer</summary> <b>B) Client stuck to distant AP</b> - Sticky client doesn't roam to closer AP. </details> **11. Which protocol is used between AP and WLC?** - A) CAPWAP - B) SNMP - C) NETCONF - D) RESTCONF <details> <summary>Answer</summary> <b>A) CAPWAP</b> - Control and Provisioning of Wireless Access Points. </details> **12. What is the recommended SNR for good wireless performance?** - A) > 10 dB - B) > 15 dB - C) > 20 dB - D) > 25 dB <details> <summary>Answer</summary> <b>D) > 25 dB</b> - SNR above 25 dB is considered good. </details> --- ## 📌 Next Steps After completing Video 55, you should be ready for: - **Video 56:** Comprehensive Lab 1 - Full Network Implementation - **Video 57:** Comprehensive Lab 2 - Troubleshooting **Lab Practice:** 1. Configure wireless network on WLC 2. Troubleshoot client connectivity issues 3. Troubleshoot AP registration issues 4. Analyze RF interference 5. Test roaming between APs --- **Ready for Video 56?** Share the link or say "next" and I'll continue with Comprehensive Lab 1 - Full Network Implementation. I'll continue with **Video 56: Comprehensive Lab 1 - Full Network Implementation** based on the standard CCNA 200-301 curriculum. ---