Wi-Fi Design
CRITICAL DESIGN ASPECTS
1. Primary Coverage Goal
OBJECTIVES
- ▶ Provide Wi-Fi service in all required location
- ▶ High-quality signal strength
- ▶ Maintain high data rates
RESULTS
- ▶ Improve airtime efficiency
- ▶ Improve density handling
2. Secondary Coverage Goal
OBJECTIVES
- ▶ Provide coverage for 2APs in each location
RESULTS
- ▶ Improve client roaming
- ▶ Low latency roaming for real-time application
- ▶ Redundancy for AP failure
3. Capacity Plan
High Client Density
Low Client Density
CONSIDERATIONS
- ▶ More spectrum in 5 GHz provides up to 8x the capacity of 2.4 GHz
- ▶ Understand client mix
- ▶ Client offered load/ SLA
- ▶ Model airtime demand
- ▶ Understand airtime saturation limits (80% BE, 50% BE/VO/VI, 35% VO)
RESULTS
- ▶ Optimal number of APs
- ▶ Proper client distribution between 5 GHz and 2.4 GHz
- ▶ Leave idle airtime for growth
Client Device Efficiency
4. Minimize Interference
OBJECTIVES
- ▶ Isolate APs on the same channel
- ▶Reduce shared airtime
- ▶ Limit contention domains
- ▶ Eliminate external interference
RESULTS
- ▶ Minimize co-channel interference (CCI) and adjacent channel interference (ACI) between APs on the same or overlapping channels
- ▶ Ideally, only one AP audible on each channel in a physical location
- ▶ Ideally, remove sources of external RF interference or avoid impacted channels if they cannot be removed
HIGH-PERFORMANCE WI-FI TIPS & TRICKS
1. Design for 5 GHz as Primary
- ▶ The 5 GHz band provides 8 times the capacity of 2.4 GHz
2. Define Coverage Goal(s)
- ▶ Too aggressive can lead to co-channel interference
- ▶ Too conservative can lead to poor client performance
3. Place APs Where Users Are Located
- ▶ In-room placement is best for client performance
- ▶ Avoid hallways, if possible unless required for voice roaming
4. Tailor Coverage to the Facility
- ▶ Leverage RF obstructions for frequency re-use
- ▶ Consider proper antennas and orientation for signal propagation
5. Fine Tune AP Power Levels
- ▶ Align with on-site signal measurements of RF propagation
- ▶ Align with AP density and frequency re-use requirements
6. Disable 2.4 GHz Radios if Necessary
- ▶ There are fewer available channels in 2.4 GHz
- ▶ Disabling radios can prevent co-channel interference and shared capacity between clients
- ▶ Some APs allow switching 2.4 GHz radio to 5 GHz
7. Design and Validate with Representative Client Devices
- ▶ Spot-check with actual client devices to ensure the design matches actual client performance
- ▶ Alternatively, measure with a standard RF site survey adapter and compensate the signal based on the actual client device characteristics
8. Higher AP Density Requires Smaller Channel Widths
- ▶ Reduces co-channel interference and shared capacity between clients
- ▶ Reduces client contention and improves network stability
9. Disable Low Data Rates to Improve Performance
- ▶ 802.11b clients can significantly impact network performance
- ▶ Reduces overhead from management frames and broadcast/multicast traffic
10. Minimized the Number of SSIDs
- ▶ Network overhead increases with each SSID defined
RF DESIGN PROCESS
1. GATHER REQUIREMENTS
- ▶ Blueprints/ CAD drawings
- ▶ Coverage areas
- ▶ Facility layouts & construction materials
- ▶ Client number and mix
- ▶ Client density distribution
- ▶ Critical applications/ business process
1. GATHER REQUIREMENTS
- ▶ Blueprints/ CAD drawings
- ▶ Coverage areas
- ▶ Facility layouts & construction materials
- ▶ Client number and mix
- ▶ Client density distribution
- ▶ Critical applications/ business process
2. PRE-INSTALLATION DESIGN
- ▶ Predictive modeling
- ▶ Wall attenuation measurements
- ▶ “AP on a stick” measurement
- ▶ Wired network integration
2. PRE-INSTALLATION DESIGN
- ▶ Predictive modeling
- ▶ Wall attenuation measurements
- ▶ “AP on a stick” measurement
- ▶ Wired network integration
3. POST INSTALLATION VALIDATION
- ▶ RF site survey (passive/ active/ spectrum)
- ▶ RF tuning channel and power plans
- ▶ Association and authentication tests
- ▶ Roaming tests
- ▶ Spectrum analysis
3. POST INSTALLATION VALIDATION
- ▶ RF site survey (passive/ active/ spectrum)
- ▶ RF tuning channel and power plans
- ▶ Association and authentication tests
- ▶ Roaming tests
- ▶ Spectrum analysis
We, at MEC, can help you achieve that with the help of Ekahau Wireless Design products.
Talk to us for inquiries or for a FREE product consultation.