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Module 45
QoS Configuration Examples
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# 📘 CCNA 200-301 - Video 45: QoS Configuration Examples ## Deep Study Notes --- ## 📌 Learning Objectives By the end of this video, you should understand: - End-to-end QoS design - Voice QoS configuration - Video QoS configuration - Data QoS configuration - Enterprise QoS deployment - QoS verification and monitoring --- ## 🧠 Core Concepts ### 1. Enterprise QoS Model **Cisco Enterprise QoS Model:** ``` ┌─────────────────────────────────────────────────────────────────────────────┐ │ ENTERPRISE QoS MODEL │ ├─────────────────────────────────────────────────────────────────────────────┤ │ │ │ CLASSIFICATION MARKING │ │ ┌─────────────────────────┐ ┌─────────────────────────┐ │ │ │ • NBAR (Application) │ │ • CoS (Layer 2) │ │ │ │ • ACL (IP/Port) │ ───► │ • DSCP (Layer 3) │ │ │ │ • Trust Boundaries │ │ • IP Precedence │ │ │ └─────────────────────────┘ └─────────────────────────┘ │ │ │ │ │ │ ▼ ▼ │ │ QUEUING (Congested Interfaces) POLICING/SHAPING │ │ ┌─────────────────────────┐ ┌─────────────────────────┐ │ │ │ • LLQ (Voice) │ │ • Policing (Ingress) │ │ │ │ • CBWFQ (Data) │ ───► │ • Shaping (Egress) │ │ │ │ • WRED (Congestion) │ │ • Rate Limiting │ │ │ └─────────────────────────┘ └─────────────────────────┘ │ │ │ └─────────────────────────────────────────────────────────────────────────────┘ ``` --- ### 2. QoS Class Definitions **Standard QoS Classes:** | Class | DSCP | Application | Bandwidth | Latency | |-------|------|-------------|-----------|---------| | **Voice** | EF (46) | VoIP | 30% | < 150 ms | | **Video** | AF41 (34) | Video conferencing | 25% | < 200 ms | | **Critical Data** | AF31 (26) | Mission-critical apps | 20% | < 300 ms | | **Business Data** | AF21 (18) | Standard business | 15% | < 500 ms | | **Best Effort** | 0 | Internet, email | Remaining | N/A | | **Scavenger** | CS1 (8) | Backup, P2P | 5% | N/A | --- ### 3. QoS Trust Boundaries ``` ┌─────────────────────────────────────────────────────────────────────────────┐ │ QoS TRUST BOUNDARIES │ ├─────────────────────────────────────────────────────────────────────────────┤ │ │ │ CAMPUS QOS TRUST BOUNDARY: │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ │ │ │ │ IP Phone Switch │ │ │ │ ┌─────────┐ ┌─────────┐ │ │ │ │ │ Phone │══════════════════│ Switch │ │ │ │ │ │(Trusted)│ │(Trusted)│ │ │ │ │ │ CoS=5 │ │ │ │ │ │ │ └─────────┘ └─────────┘ │ │ │ │ │ │ │ │ │ │ PC (Untrusted) │ │ │ │ │ ┌─────────┐ │ │ │ │ │ │ PC │ │ │ │ │ │ │(Untrusted)│ │ │ │ │ │ │ DSCP=0 │ │ │ │ │ │ └─────────┘ ▼ │ │ │ │ Router (Trusted) │ │ │ │ ┌─────────┐ │ │ │ │ │ Router │ │ │ │ │ │(Trusted)│ │ │ │ │ └─────────┘ │ │ │ │ │ │ │ │ │ │ WAN │ │ │ │ ▼ │ │ │ │ Service Provider │ │ │ │ (Untrusted) │ │ │ │ │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ │ Trust Boundary Rules: │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ • Trust IP phones and IP phones marking │ │ │ │ • Do NOT trust PCs (they may mark incorrectly) │ │ │ │ • Trust routers and switches (re-mark if needed) │ │ │ │ • Do NOT trust service provider (re-mark at edge) │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ └─────────────────────────────────────────────────────────────────────────────┘ ``` --- ### 4. Voice QoS Configuration **Voice Traffic Requirements:** - One-way latency: < 150 ms - Jitter: < 30 ms - Packet loss: < 1% - Bandwidth per call: ~80-100 kbps (G.711) ``` ┌─────────────────────────────────────────────────────────────────────────────┐ │ VOICE QOS ARCHITECTURE │ ├─────────────────────────────────────────────────────────────────────────────┤ │ │ │ Access Layer Distribution/Core │ │ │ │ ┌─────────┐ ┌─────────────────────────────┐ │ │ │ IP Phone│───┐ │ │ │ │ │ CoS=5 │ │ │ LLQ: 30% (Voice) │ │ │ └─────────┘ │ │ CBWFQ: 25% (Video) │ │ │ │ │ 20% (Critical Data) │ │ │ ┌─────────┐ │ ┌─────────┐ │ │ │ │ │ PC │───┼───│ Switch │────────│ Router │ │ │ │ DSCP=0 │ │ │(Trusted)│ │ │ │ │ └─────────┘ │ └─────────┘ └─────────────────────────────┘ │ │ │ │ │ │ │ ┌─────────┐ │ │ │ │ │ │ IP Phone│───┘ │ │ │ │ │ CoS=5 │ │ │ │ │ └─────────┘ │ │ │ │ │ │ │ │ ┌──────▼──────┐ │ │ │ │ Switch │ │ │ │ │(Trust Voice)│ │ │ │ └─────────────┘ │ │ │ │ │ └─────────────────────────────────────────────────────────────────────────────┘ ``` **Switch Configuration (Access Layer):** ```cisco ! Configure IP phone trust interface FastEthernet0/1 switchport mode access switchport voice vlan 10 switchport access vlan 20 mls qos trust device cisco-phone mls qos trust cos auto qos voip cisco-phone ``` **Router Configuration (WAN Edge):** ```cisco ! Class maps class-map VOICE match ip dscp ef class-map VIDEO match ip dscp af41 class-map CRITICAL match ip dscp af31 ! Policy map for WAN policy-map WAN-QOS class VOICE priority percent 30 class VIDEO bandwidth percent 25 class CRITICAL bandwidth percent 20 class class-default fair-queue random-detect ! Apply to WAN interface interface Serial0/0/0 service-policy output WAN-QOS ``` --- ### 5. Video QoS Configuration **Video Traffic Requirements:** - One-way latency: < 200 ms - Jitter: < 50 ms - Packet loss: < 1% - Bandwidth: 1-4 Mbps per stream ```cisco ! Class map for video class-map VIDEO match ip dscp af41 ! Policy with video class policy-map VIDEO-QOS class VOICE priority percent 30 class VIDEO bandwidth percent 25 random-detect dscp-based class class-default fair-queue interface GigabitEthernet0/0 service-policy output VIDEO-QOS ``` --- ### 6. Data QoS Configuration **Critical Data Traffic:** - Mission-critical applications - Database replication - ERP/CRM systems ```cisco ! Class maps for data class-map CRITICAL match ip dscp af31 class-map BUSINESS match ip dscp af21 class-map SCAVENGER match ip dscp cs1 ! Policy map for data policy-map DATA-QOS class CRITICAL bandwidth percent 20 random-detect dscp-based class BUSINESS bandwidth percent 15 random-detect dscp-based class SCAVENGER bandwidth percent 5 random-detect dscp-based class class-default fair-queue random-detect interface GigabitEthernet0/0 service-policy output DATA-QOS ``` --- ### 7. Auto QoS Configuration **Cisco Auto QoS simplifies QoS deployment:** ```cisco ! Auto QoS on switch interface FastEthernet0/1 auto qos voip cisco-phone ! Auto QoS on router (WAN) interface Serial0/0/0 auto qos voip ! Auto QoS on router (trust) interface GigabitEthernet0/0 auto qos trust ``` **Auto QoS Generated Configuration:** ```cisco ! Auto QoS creates these configurations automatically: ! class-map match-any AutoQoS-VoIP-RTP match ip dscp ef ! class-map match-any AutoQoS-VoIP-Control match ip dscp af31 match ip dscp cs3 ! policy-map AutoQoS-Policy class AutoQoS-VoIP-RTP priority percent 30 class AutoQoS-VoIP-Control bandwidth percent 5 class class-default fair-queue ! interface Serial0/0/0 service-policy output AutoQoS-Policy ``` --- ### 8. Campus QoS Configuration Example ``` ┌─────────────────────────────────────────────────────────────────────────────┐ │ CAMPUS QOS CONFIGURATION │ ├─────────────────────────────────────────────────────────────────────────────┤ │ │ │ Access Layer Switch: │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ ! Global QoS │ │ │ │ mls qos │ │ │ │ │ │ │ │ ! Interface to IP phone │ │ │ │ interface FastEthernet0/1 │ │ │ │ switchport mode access │ │ │ │ switchport voice vlan 10 │ │ │ │ switchport access vlan 20 │ │ │ │ mls qos trust device cisco-phone │ │ │ │ mls qos trust cos │ │ │ │ │ │ │ │ ! Interface to PC (untrusted) │ │ │ │ interface FastEthernet0/2 │ │ │ │ switchport mode access │ │ │ │ switchport access vlan 20 │ │ │ │ mls qos cos 0 │ │ │ │ │ │ │ │ ! Uplink to distribution (trusted) │ │ │ │ interface GigabitEthernet0/24 │ │ │ │ switchport mode trunk │ │ │ │ mls qos trust dscp │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ │ Distribution Switch: │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ ! Global QoS │ │ │ │ mls qos │ │ │ │ │ │ │ │ ! Uplink to core (trusted) │ │ │ │ interface GigabitEthernet0/24 │ │ │ │ switchport mode trunk │ │ │ │ mls qos trust dscp │ │ │ │ │ │ │ │ ! Downlink to access (trusted) │ │ │ │ interface GigabitEthernet0/1 │ │ │ │ switchport mode trunk │ │ │ │ mls qos trust dscp │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ └─────────────────────────────────────────────────────────────────────────────┘ ``` --- ### 9. WAN QoS Configuration Example ``` ┌─────────────────────────────────────────────────────────────────────────────┐ │ WAN QOS CONFIGURATION │ ├─────────────────────────────────────────────────────────────────────────────┤ │ │ │ Customer Router (CE) │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ ! Classification │ │ │ │ class-map VOICE │ │ │ │ match ip dscp ef │ │ │ │ │ │ │ │ class-map VIDEO │ │ │ │ match ip dscp af41 │ │ │ │ │ │ │ │ class-map CRITICAL │ │ │ │ match ip dscp af31 │ │ │ │ │ │ │ │ class-map BUSINESS │ │ │ │ match ip dscp af21 │ │ │ │ │ │ │ │ ! Queuing Policy │ │ │ │ policy-map WAN-QOS │ │ │ │ class VOICE │ │ │ │ priority percent 30 │ │ │ │ class VIDEO │ │ │ │ bandwidth percent 25 │ │ │ │ class CRITICAL │ │ │ │ bandwidth percent 20 │ │ │ │ class BUSINESS │ │ │ │ bandwidth percent 10 │ │ │ │ class class-default │ │ │ │ fair-queue │ │ │ │ random-detect │ │ │ │ │ │ │ │ ! Shaping Policy │ │ │ │ policy-map SHAPE-WAN │ │ │ │ class class-default │ │ │ │ shape average 10000000 │ │ │ │ service-policy WAN-QOS │ │ │ │ │ │ │ │ ! Apply to WAN interface │ │ │ │ interface Serial0/0/0 │ │ │ │ service-policy output SHAPE-WAN │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ └─────────────────────────────────────────────────────────────────────────────┘ ``` --- ### 10. Service Provider QoS Configuration ``` ┌─────────────────────────────────────────────────────────────────────────────┐ │ SERVICE PROVIDER QOS │ ├─────────────────────────────────────────────────────────────────────────────┤ │ │ │ Provider Edge (PE) Router: │ │ ┌─────────────────────────────────────────────────────────────────────┐ │ │ │ ! Mark customer traffic │ │ │ │ policy-map MARK-CUSTOMER │ │ │ │ class class-default │ │ │ │ set mpls experimental 3 │ │ │ │ │ │ │ │ interface GigabitEthernet0/0 │ │ │ │ service-policy input MARK-CUSTOMER │ │ │ │ │ │ │ │ ! Police to enforce SLA │ │ │ │ policy-map POLICE-CUSTOMER │ │ │ │ class class-default │ │ │ │ police cir 10000000 │ │ │ │ conform-action transmit │ │ │ │ exceed-action drop │ │ │ │ │ │ │ │ interface GigabitEthernet0/0 │ │ │ │ service-policy input POLICE-CUSTOMER │ │ │ └─────────────────────────────────────────────────────────────────────┘ │ │ │ └─────────────────────────────────────────────────────────────────────────────┘ ``` --- ### 11. QoS Verification Commands | Command | Purpose | |---------|---------| | `show policy-map interface [int]` | Display QoS statistics | | `show mls qos interface [int]` | Display switch QoS status | | `show auto qos` | Display auto QoS configuration | | `show class-map` | Display class maps | | `show policy-map` | Display policy maps | | `show queueing interface [int]` | Display queue statistics | **Example Outputs:** ```cisco Router# show policy-map interface serial 0/0/0 Serial0/0/0 Service-policy output: SHAPE-WAN Class-map: class-default (match-any) 123456 packets, 12345678 bytes 5 minute offered rate 8000000 bps, drop rate 0 bps Match: any Traffic Shaping Target/Average Peak Rate Excess Rate Limit Bits/Int 10000000 31250 10000000 10000000 Adapt Queue Packets Bytes Packets Bytes Shaping Active Depth Delayed Delayed Active - 0 123456 12345678 0 0 no Service-policy : WAN-QOS Class-map: VOICE (match-all) 1234 packets, 123456 bytes 5 minute offered rate 100000 bps, drop rate 0 bps Match: ip dscp ef (46) Strict Priority Output Queue: Conversation 264 Bandwidth 30 (%) Bandwidth 3000 (kbps) Burst 75000 (Bytes) (pkts matched/bytes matched) 1234/123456 (total drops/bytes drops) 0/0 Class-map: VIDEO (match-all) 2345 packets, 234567 bytes 5 minute offered rate 200000 bps, drop rate 0 bps Match: ip dscp af41 (34) Queueing Output Queue: Conversation 265 Bandwidth 25 (%) Bandwidth 2500 (kbps) Max Threshold 64 (packets) (pkts matched/bytes matched) 2345/234567 (depth/total drops/no-buffer drops) 0/0/0 Class-map: class-default (match-any) 119877 packets, 11987655 bytes 5 minute offered rate 7700000 bps, drop rate 0 bps Match: any Queueing Output Queue: Conversation 266 Bandwidth 10 (%) Bandwidth 1000 (kbps) Max Threshold 64 (packets) (pkts matched/bytes matched) 119877/11987655 (depth/total drops/no-buffer drops) 0/0/0 ``` --- ## 🔧 Complete Configuration Examples ### Lab 1: Enterprise QoS End-to-End **Access Switch Configuration:** ```cisco hostname Access-Switch ! ! Enable QoS globally mls qos ! ! IP phone interface interface FastEthernet0/1 switchport mode access switchport voice vlan 10 switchport access vlan 20 mls qos trust device cisco-phone mls qos trust cos ! ! PC interface (untrusted) interface FastEthernet0/2 switchport mode access switchport access vlan 20 mls qos cos 0 ! ! Uplink to distribution (trusted) interface GigabitEthernet0/24 switchport mode trunk mls qos trust dscp ! end ``` **Distribution Switch Configuration:** ```cisco hostname Dist-Switch ! mls qos ! ! Downlink to access (trusted) interface GigabitEthernet0/1 switchport mode trunk mls qos trust dscp ! ! Uplink to core (trusted) interface GigabitEthernet0/24 switchport mode trunk mls qos trust dscp ! end ``` **WAN Router Configuration:** ```cisco hostname WAN-Router ! ! Class maps class-map VOICE match ip dscp ef class-map VIDEO match ip dscp af41 class-map CRITICAL match ip dscp af31 class-map BUSINESS match ip dscp af21 ! ! Queuing policy policy-map WAN-QUEUE class VOICE priority percent 30 class VIDEO bandwidth percent 25 class CRITICAL bandwidth percent 20 class BUSINESS bandwidth percent 10 class class-default fair-queue random-detect ! ! Shaping policy policy-map WAN-SHAPE class class-default shape average 10000000 service-policy WAN-QUEUE ! ! Apply to WAN interface interface Serial0/0/0 service-policy output WAN-SHAPE ! end ``` --- ### Lab 2: Auto QoS Configuration **Switch Auto QoS:** ```cisco ! Configure Auto QoS on switch interface FastEthernet0/1 auto qos voip cisco-phone ! Verify Auto QoS configuration show auto qos show policy-map ``` **Router Auto QoS:** ```cisco ! Configure Auto QoS on router interface Serial0/0/0 auto qos voip ! Verify show auto qos show policy-map interface serial0/0/0 ``` --- ### Lab 3: Voice and Video QoS ```cisco hostname Voice-Video-Router ! ! Class maps class-map VOICE match ip dscp ef class-map VIDEO-CONTROL match ip dscp af41 class-map VIDEO-PAYLOAD match ip dscp af42 ! ! Policy map policy-map VOICE-VIDEO-QOS class VOICE priority percent 30 class VIDEO-CONTROL bandwidth percent 5 class VIDEO-PAYLOAD bandwidth percent 20 class class-default fair-queue ! interface Serial0/0/0 service-policy output VOICE-VIDEO-QOS ! end ``` --- ### Lab 4: Data Center QoS ```cisco hostname DataCenter-Router ! ! Class maps for storage and database class-map STORAGE match ip dscp af41 class-map DATABASE match ip dscp af31 class-map MANAGEMENT match ip dscp cs2 ! ! Policy map policy-map DC-QOS class STORAGE bandwidth percent 30 random-detect dscp-based class DATABASE bandwidth percent 25 random-detect dscp-based class MANAGEMENT bandwidth percent 5 class class-default fair-queue ! interface GigabitEthernet0/0 service-policy output DC-QOS ! end ``` --- ## ✅ Exam Tips (For CCNA 200-301) | Topic | What Cisco Tests | |-------|------------------| | **Trust Boundary** | Trust IP phones, do not trust PCs | | **Voice QoS** | LLQ (priority), 30% bandwidth, low latency | | **Auto QoS** | Simplifies QoS deployment | | **Enterprise QoS Model** | Classification, Marking, Queuing, Policing/Shaping | | **WAN QoS** | Shaping + LLQ | | **Campus QoS** | Trust boundaries, marking at access layer | ### Common Exam Scenarios: **Scenario 1:** "Where should the QoS trust boundary be in a campus network with IP phones?" - **Answer:** At the access switch, trusting the IP phone but not the PC **Scenario 2:** "Which QoS mechanism should be used for voice traffic on a WAN link?" - **Answer:** LLQ (Low-Latency Queuing) with priority queue **Scenario 3:** "What is the purpose of Auto QoS?" - **Answer:** Automatically configures QoS based on device type and network requirements ### Mnemonics: **QoS Deployment Steps:** **"C.M.Q.P.S." - Classify, Mark, Queue, Police, Shape** - **C**lassify: Identify traffic - **M**ark: Tag traffic - **Q**ueue: Manage buffers - **P**olice: Enforce limits (ingress) - **S**hape: Smooth traffic (egress) **Trust Boundary Rules:** **"Trust Phones, Not PCs"** - Trust IP phones (they mark correctly) - Do not trust PCs (they may mark incorrectly) --- ## 📝 Summary (1-Minute Revision) ``` QOS CONFIGURATION EXAMPLES: CAMPUS QOS: ├── Access Switch: Trust IP phones, untrust PCs ├── Distribution/Core: Trust DSCP └── Command: mls qos trust dscp VOICE QOS: ├── Class: match ip dscp ef ├── LLQ: priority percent 30 ├── Requirements: <150 ms latency, <1% loss └── Auto QoS: auto qos voip VIDEO QOS: ├── Class: match ip dscp af41 ├── Bandwidth: percent 25 ├── WRED: random-detect dscp-based └── Requirements: <200 ms latency DATA QOS: ├── Critical: match af31, bandwidth 20% ├── Business: match af21, bandwidth 15% ├── Best Effort: class-default └── Scavenger: match cs1, bandwidth 5% WAN QOS: ├── Shaping: shape average [cir] ├── Queuing: LLQ + CBWFQ └── Hierarchical: shape average + service-policy AUTO QOS: ├── switch: auto qos voip cisco-phone ├── router: auto qos voip └── trust: auto qos trust VERIFICATION: ├── show policy-map interface ├── show mls qos interface ├── show auto qos └── show queueing interface ``` --- ## 🧪 Practice Questions **1. Where should the QoS trust boundary be in a campus network with IP phones?** - A) At the core switch - B) At the distribution switch - C) At the access switch, trusting the IP phone - D) At the PC <details> <summary>Answer</summary> <b>C) At the access switch, trusting the IP phone</b> - The trust boundary is at the access switch, trusting the IP phone but not the PC. </details> **2. Which QoS mechanism should be used for voice traffic on a WAN link?** - A) CBWFQ - B) LLQ - C) FIFO - D) WFQ <details> <summary>Answer</summary> <b>B) LLQ</b> - Low-Latency Queuing provides a strict priority queue for voice. </details> **3. What is the recommended bandwidth percentage for voice in LLQ?** - A) 10% - B) 20% - C) 30% - D) 50% <details> <summary>Answer</summary> <b>C) 30%</b> - 30% is the recommended maximum for priority queue. </details> **4. Which command enables Auto QoS on a switch port with an IP phone?** - A) `auto qos voip` - B) `auto qos voip cisco-phone` - C) `auto qos trust` - D) `mls qos auto` <details> <summary>Answer</summary> <b>B) `auto qos voip cisco-phone`</b> - Auto QoS for Cisco IP phones. </details> **5. Which DSCP value is used for voice (EF)?** - A) 34 - B) 26 - C) 46 - D) 18 <details> <summary>Answer</summary> <b>C) 46</b> - EF (Expedited Forwarding) is DSCP 46 for voice. </details> **6. What is the recommended one-way latency for voice traffic?** - A) < 50 ms - B) < 100 ms - C) < 150 ms - D) < 200 ms <details> <summary>Answer</summary> <b>C) < 150 ms</b> - Voice requires less than 150 ms one-way latency. </details> **7. Which command displays QoS statistics on an interface?** - A) `show qos` - B) `show policy-map interface` - C) `show mls qos` - D) `show interface qos` <details> <summary>Answer</summary> <b>B) `show policy-map interface`</b> - Displays QoS policy statistics. </details> **8. What is the purpose of hierarchical QoS on a WAN link?** - A) Combine shaping and queuing - B) Combine policing and marking - C) Combine classification and queuing - D) Combine marking and shaping <details> <summary>Answer</summary> <b>A) Combine shaping and queuing</b> - Parent policy shapes, child policy queues. </details> **9. Which QoS class should be used for scavenger traffic (P2P, backup)?** - A) EF - B) AF41 - C) AF31 - D) CS1 <details> <summary>Answer</summary> <b>D) CS1</b> - Scavenger traffic uses DSCP CS1 (8). </details> **10. Which command trusts the DSCP marking on a switch trunk port?** - A) `mls qos trust cos` - B) `mls qos trust dscp` - C) `mls qos trust ip` - D) `mls qos trust` <details> <summary>Answer</summary> <b>B) `mls qos trust dscp`</b> - Trusts DSCP markings on the trunk. </details> **11. What is the recommended bandwidth percentage for video in CBWFQ?** - A) 10% - B) 15% - C) 20% - D) 25% <details> <summary>Answer</summary> <b>D) 25%</b> - Video typically gets 25% guaranteed bandwidth. </details> **12. Which command displays the Auto QoS configuration?** - A) `show auto qos` - B) `show qos auto` - C) `show mls qos auto` - D) `show policy-map auto` <details> <summary>Answer</summary> <b>A) `show auto qos`</b> - Displays the Auto QoS configuration. </details> --- ## 📌 Next Steps After completing Video 45, you should be ready for: - **Video 46:** CDP and LLDP - **Video 47:** NTP and SNMP (Advanced) **Lab Practice:** 1. Configure Auto QoS on a switch port 2. Configure LLQ for voice on a router 3. Configure hierarchical QoS on a WAN link 4. Verify with `show policy-map interface` 5. Test with voice and video traffic 6. Monitor drops and latency --- **Ready for Video 46?** Share the link or say "next" and I'll continue with CDP and LLDP. I'll continue with **Video 46: CDP and LLDP** based on the standard CCNA 200-301 curriculum. ---