802.11r Channels

Does 802.11r define specific channels?

No, 802.11r works over existing Wi-Fi channels in 2.4 GHz or 5 GHz bands; it doesn’t define new channels.

How does 802.11r improve roaming across different channels?

It speeds up key negotiation and authentication, allowing faster handoff even when moving between APs on different channels.

Can 802.11r handle roaming between 2.4 GHz and 5 GHz channels?

Yes, 802.11r supports fast transitions even when roaming between different frequency bands.

Does channel switching during roaming affect 802.11r performance?

Minimal impact, since 802.11r reduces handoff time significantly regardless of channel changes.

What role do channels play in 802.11r Fast Transition?

Channels determine where the client associates next, but 802.11r optimizes security and authentication during the switch.

Is the client aware of channel changes during 802.11r roaming?

Yes, the client scans and switches channels as needed; 802.11r ensures the transition is quick and seamless.

Does 802.11r support roaming on overlapping channels?

Yes, but overlapping channels can cause interference, so proper channel planning is still essential.

How does channel width affect 802.11r roaming?

Roaming works similarly on 20 MHz or wider channels; channel width doesn’t impact the fast transition process directly.

Can 802.11r reduce roaming delays caused by channel changes?

Yes, by pre-authenticating and caching keys, it minimizes delays when clients switch channels.

Does 802.11r require APs on the same channel for fast roaming?

No, APs can be on different channels; 802.11r manages roaming across channels efficiently.

How does 802.11r interact with DFS channels during roaming?

It supports roaming onto DFS channels but must comply with DFS regulations and radar detection requirements.

Can 802.11r improve roaming in environments with many channel options?

Yes, it makes transitions between APs on different channels smoother and faster.

Is there any difference in 802.11r roaming on 2.4 GHz vs 5 GHz channels?

802.11r speeds roaming equally on both bands, but 5 GHz often offers more channels and less interference.

Does channel interference impact 802.11r fast roaming?

Indirectly — interference affects signal quality, but 802.11r reduces authentication delays regardless.

What happens if an AP moves to a new channel in an 802.11r network?

Clients using 802.11r will re-associate quickly on the new channel due to fast transition capabilities.

Does 802.11r require special channel coordination among APs?

No special coordination is required, but good channel planning still improves overall network performance.

Can 802.11r support roaming between APs on different regulatory channels?

Only if allowed by the regulatory domain; otherwise, roaming between disallowed channels is not possible.

How does 802.11r handle roaming when channel availability is limited?

It still reduces handoff times, but limited channel options may increase contention and interference.

Does 802.11r impact how clients scan channels during roaming?

It reduces the need for full re-authentication, but clients still scan channels to find the best AP.

Topics in this section,

Channel Number (MHz)

Center Frequency (MHz)

Frequency Range

DFS Required

1

2412

2401 – 2423

No

2

2417

2406 – 2428

No

3

2422

2411 – 2433

No

4

2427

2416 – 2438

No

5

2432

2421 – 2443

No

6

2437

2426 – 2448

No

7

2442

2431 – 2453

No

8

2447

2436 – 2458

No

9

2452

2441 – 2463

No

10

2457

2446 – 2468

No

11

2462

2451 – 2473

No

12

2467

2456 – 2478

No (region dependent)

13

2472

2461 – 2483

No (region dependent)

14

2484

2473 – 2495

No (Japan only)

Channel Number (MHz)

Center Frequency (MHz)

Frequency Range

DFS Required

36

5180

5170 – 5190

No

40

5200

5190 – 5210

No

44

5220

5210 – 5230

No

48

5240

5230 – 5250

No

52

5260

5250 – 5270

Yes

56

5280

5270 – 5290

Yes

60

5300

5290 – 5310

Yes

64

5320

5310 – 5330

Yes

100

5500

5490 – 5510

Yes

104

5520

5510 – 5530

Yes

108

5540

5530 – 5550

Yes

112

5560

5550 – 5570

Yes

116

5580

5570 – 5590

Yes

120

5600

5590 – 5610

Yes

124

5620

5610 – 5630

Yes

128

5640

5630 – 5650

Yes

132

5660

5650 – 5670

Yes

136

5680

5670 – 5690

Yes

140

5700

5690 – 5710

Yes

144

5720

5710 – 5730

Yes

149

5745

5735 – 5755

No

153

5765

5755 – 5775

No

157

5785

5775 – 5795

No

161

5805

5795 – 5815

No

165

5825

5815 – 5835

No

  • channel widths

Band Name

Frequency Range (GHz)

Frequency Range (MHz)

Channels

2.4 GHz Band

2.400 – 2.485

2400 – 2485

1 – 14 (region dependent)

UNII-1

5.150 – 5.250

5150 – 5250

36, 40, 44, 48

UNII-2 (DFS)

5.250 – 5.350

5250 – 5350

52, 56, 60, 64

UNII-2 Extended (DFS)

5.470 – 5.725

5470 – 5725

100, 104, 108, 112, 116, 120, 124, 128, 132, 136, 140, 144

UNII-3

5.725 – 5.825

5725 – 5825

149, 153, 157, 161, 165

  • Reference links