Band Selection Guide

Band Overview

Band	Frequency	Typical Range	Max Speed (WiFi 6)	Interference	Best For
2.4 GHz	2400-2500 MHz	50-70m indoor	600 Mbps	High	Legacy devices, IoT, long range
5 GHz	5150-5850 MHz	30-40m indoor	4.8 Gbps	Low	High throughput, modern devices
6 GHz	5925-7125 MHz	20-30m indoor	9.6 Gbps	Minimal	Ultra-high throughput, dense environments

2.4 GHz Band

When to Use 2.4 GHz

The 2.4 GHz band remains essential for:

IoT and smart home devices - Most IoT devices (smart bulbs, sensors, switches) only support 2.4 GHz
Legacy device support - Older smartphones, laptops, and tablets may not support 5 GHz
Longer range coverage - Better penetration through walls and obstacles
Outdoor deployments - Extended range for yard, patio, or warehouse coverage

2.4 GHz Characteristics

Advantages:

Longer wavelength penetrates walls and obstacles better
Works with more devices (100% WiFi compatibility)
Better range, especially outdoors
Lower cost hardware
Less congestion in most areas (vs 5 GHz in urban areas)

Disadvantages:

Limited channels (only 3 non-overlapping)
Heavily congested in urban environments
Slower maximum speeds
More susceptible to interference (microwaves, Bluetooth, cordless phones)

Channel Planning

Only three non-overlapping channels exist in 2.4 GHz:

Channel	Center Frequency	Primary Use
1	2412 MHz	Coverage area A
6	2437 MHz	Coverage area B
11	2462 MHz	Coverage area C

Critical: Never use channels 2-5 or 7-10 for primary APs. These overlap with channels 1, 6, and 11 and cause more interference than using adjacent channels.

2.4 GHz Configuration

# Legacy wireless package
/interface wireless channel add name=2.4GHz-20MHz band=2ghz-b/g/n frequency=2437 channel-width=20mhz

# WiFi package
/interface wifi channel add name=2.4GHz band=2ghz-b/g/n/ax frequency=2437 channel-width=20mhz

IoT Deployment Strategy

For IoT-heavy networks:

# Separate IoT network
/interface wifi security add name=IoT-Security authentication-types=wpa2-psk passphrase=IoTPass123!

/interface wifi datapath add name=IoT-DP bridge=bridge-iot vlan-id=100

/interface wifi configuration add name=IoT-AP \
    ssid=SmartHome \
    security=IoT-Security \
    datapath=IoT-DP \
    country=UnitedStates

IoT Recommendations:

Use separate SSID/VLAN for IoT devices
Disable 5 GHz on IoT-only networks
Use WPA2-PSK (most IoT devices don’t support WPA3)
Consider disabling client isolation for device-to-device communication

5 GHz Band

When to Use 5 GHz

The 5 GHz band is recommended for:

High-throughput applications - 4K streaming, large file transfers, video conferencing
Modern devices - Any device from 2015+ typically supports 5 GHz
Dense environments - More available channels reduces interference
Business networks - Better performance for employee and guest networks

5 GHz Characteristics

Advantages:

Many more non-overlapping channels (25+)
Much faster maximum speeds (up to 4.8 Gbps with WiFi 6)
Less interference from non-WiFi devices
Better performance in dense environments

Disadvantages:

Shorter range (reduced by ~30% vs 2.4 GHz)
Worse penetration through walls
Not supported by some legacy devices
DFS restrictions in some regions

Available Channels

UNII Band	Channels	Frequency	DFS Required	Max Power
UNII-1	36, 40, 44, 48	5150-5250 MHz	No	23 dBm
UNII-2	52, 56, 60, 64	5250-5330 MHz	Yes	23 dBm
UNII-2 Extended	100-144	5470-5720 MHz	Yes	23 dBm
UNII-3	149-165	5725-5850 MHz	No	30 dBm

Recommended Channels

Non-DFS (No radar avoidance needed):

36 (5180 MHz) - Primary recommendation
40 (5200 MHz)
44 (5220 MHz)
48 (5240 MHz)
149 (5745 MHz)
153 (5765 MHz)
157 (5785 MHz)
161 (5805 MHz)

Channel Width Selection

Width	Throughput	Interference Risk	Best Environment
20 MHz	Moderate	Low	Dense, legacy devices
40 MHz	High	Medium	Standard deployments
80 MHz	Very High	High	Open environments
160 MHz	Maximum	Very High	Clean spectrum available

Recommendation: Use 80 MHz as default for 5 GHz. Reserve 160 MHz for specific high-throughput needs.

5 GHz Configuration

# WiFi package - 80 MHz channel
/interface wifi channel add name=5GHz-80MHz \
    band=5ghz-a/n/ac/ax \
    frequency=5180,5200,5220,5240 \
    channel-width=80mhz

# Legacy wireless package
/interface wireless channel add name=5GHz-80MHz \
    band=5ghz-a/n/ac \
    frequency=5180 \
    channel-width=80mhz

DFS Considerations

DFS channels (52-64, 100-144) can be affected by:

Radar detection - Immediate channel switch required
30-minute blocking - After radar detection, channel is blocked for 30 minutes
Weather radar - Can trigger DFS on adjacent channels

For reliable 5 GHz operation, prefer non-DFS channels (36-48, 149-165).

For comprehensive information on DFS behavior, deployment strategies, and workarounds, see DFS Channels.

Dual-Band Strategy

Most deployments should use both 2.4 GHz and 5 GHz on the same SSID for seamless client experience.

Unified SSID (Recommended)

# Create single configuration for both bands
/interface wifi configuration add name=DualBand-AP \
    ssid=Office-Network \
    security=corp-sec \
    datapath=corp-dp \
    country=UnitedStates

# Apply to both radios
/interface wifi set [find name="wifi1"] configuration=DualBand-AP
/interface wifi set [find name="wifi2"] configuration=DualBand-AP

Separate SSIDs

For specialized deployments:

# High-performance 5 GHz only
/interface wifi configuration add name=5GHz-Performance \
    ssid=Office-5G-Only \
    security=corp-sec \
    channel=5GHz-80MHz

# IoT/legacy 2.4 GHz only
/interface wifi configuration add name=2.4GHz-IoT \
    ssid=Office-IoT \
    security=IoT-sec \
    channel=2.4GHz

Deployment Scenarios

Home Network

Device Type	Recommended Band	Channel Width	Notes
Streaming (4K)	5 GHz	80 MHz	High throughput needed
Smartphones	5 GHz (auto)	80 MHz	Most modern phones support it
Smart TV	5 GHz	40-80 MHz	Wired preferred if possible
IoT Devices	2.4 GHz	20 MHz	Legacy compatibility
Guests	5 GHz	40 MHz	Security isolation

Office Network

Scenario	Recommendation
Open floor plan	5 GHz with 80 MHz, APs every 30m
Dense client count	5 GHz with 20/40 MHz, more APs
Conference rooms	Dedicated 5 GHz SSID
IoT/smart building	Separate 2.4 GHz SSID + VLAN
Roaming users	Enable band steering

Outdoor/Warehouse

Scenario	Recommendation
Yard/coverage	2.4 GHz, lower channels (1/6/11)
Warehouse (line-of-sight)	60 GHz (W60G) for fixed links
Outdoor point-to-point	5 GHz with 40 MHz, high-gain antennas
Loading dock	2.4 GHz for legacy scanners

Dense Environments

For apartments, dormitories, or dense office:

Use 5 GHz exclusively - Higher capacity
Reduce channel width - 20 or 40 MHz to reduce interference
Increase AP count - Lower transmit power, more APs
Use lower UNII-1 channels - 36-48 avoid DFS
Implement minimum RSSI - Prevent weak client associations

# Minimum signal strength to accept clients
/interface wifi access-list
add action=accept signal-range=-70..120
add action=reject signal-range=-120..-71

Band Steering

Band steering encourages dual-band clients to use 5 GHz for better performance.

Enabling Band Steering

/interface wifi configuration set [find] \
    band-steering=yes

Note: Some devices may experience issues with aggressive band steering. Test thoroughly with all device types.

Channel Planning Best Practices

Multi-AP Environments

Non-overlapping channels - Ensure APs don’t share channels within coverage overlap
Reduce power - Lower tx-power to reduce co-channel interference:

/interface wifi set [find] tx-power=17

Adjacent channel spacing - Space channels by 4+ channels in 5 GHz

Channel Selection Algorithm

For each AP:
  1. Scan environment for existing WiFi
  2. Identify least congested non-DFS channels
  3. Assign channel with maximum separation from neighbors
  4. For 2.4 GHz: Use 1, 6, or 11 only
  5. For 5 GHz: Prefer 36, 40, 44, 48 (non-DFS)

Signal Strength Reference

Application	2.4 GHz Target	5 GHz Target
VoIP/Video	-60 dBm	-65 dBm
Streaming	-65 dBm	-70 dBm
Web Browsing	-70 dBm	-75 dBm
Basic Connectivity	-80 dBm	-80 dBm

Troubleshooting Band Selection

Clients Stuck on 2.4 GHz

Check client capability - Older devices may not support 5 GHz
Verify AP 5 GHz is enabled - Confirm radio is not disabled
Reduce 5 GHz power - If 2.4 GHz signal is much stronger
Enable band steering - Push clients to 5 GHz

Poor 5 GHz Performance

Check channel width - Reduce from 160 MHz to 80 MHz
Verify DFS isn’t triggering - Check logs for radar detection
Scan for interference - Other APs may be on same channel
Check AP density - Too many APs can cause self-interference

IoT Device Connectivity

Confirm 2.4 GHz only - Most IoT devices don’t support 5 GHz
Check security type - IoT often requires WPA2-PSK
Verify SSID visibility - Some IoT devices have issues with hidden SSIDs
Check client isolation - May block device-to-device communication

WiFi 6 and RouterOS 7 WiFi Package - WiFi 6 configuration
CAPsMAN - Centralized management for multiple APs
Fast Roaming - 802.11r/k/v roaming between APs
Security Profiles - WPA2/WPA3 configuration