Wi-Fi 7 (802.11be): what MLO actually changes

802.11be is the first Wi-Fi generation in some time whose headline feature is genuinely architectural rather than incremental. That feature is Multi-Link Operation. Most of the rest is the usual widening and denser modulation.

Multi-Link Operation (MLO)

Before Wi-Fi 7, a client associated with one AP on one band on one channel. MLO lets a client associate once and maintain simultaneous links across multiple bands — typically 5 GHz and 6 GHz together, sometimes all three.

Two operating modes matter:

STR (Simultaneous Transmit and Receive) — the client genuinely uses both links at once. Throughput aggregates, and latency drops because a frame can go out on whichever link is free. Requires enough radio isolation between the links, which in practice means non-adjacent bands.
eMLSR / eMLMR (enhanced Multi-Link Single Radio / Multi-Radio) — the client listens on multiple links but transmits on one, switching in microseconds. Cheaper and more power-efficient; the win is latency and reliability rather than raw aggregate throughput. Most phones and many laptops implement this rather than full STR.

The real benefit is not peak throughput, it is latency consistency. If the 6 GHz link takes a hit from interference or a client walks behind a wall, traffic continues on the 5 GHz link without a roam, without a DHCP renewal, without a dropped call. For real-time applications this is a bigger deal than any megabit figure.

Deployment implication: MLO changes how you think about band steering. Steering a Wi-Fi 7 client to a single "best" band actively works against MLO. Check that your controller understands multi-link clients before you enable aggressive steering.

320 MHz channels

Only available at 6 GHz, and only where the regulator opened the full 1200 MHz. In the EU and UK, with 500 MHz allocated, a 320 MHz channel consumes most of the band and leaves you with essentially one channel — which is not a plan.

Even in the US, a 320 MHz channel raises the noise floor 12 dB above 20 MHz. It is excellent for a demonstration and for point-to-point links. It is rarely the right choice in an office.

4096-QAM (4K-QAM)

A 20 percent peak-rate improvement over 1024-QAM, requiring roughly 40 dB SNR to sustain. That is a few metres from the AP with clean spectrum. Real, useful in the right place, and irrelevant to the coverage edge where users actually complain.

Multi-RU and preamble puncturing

Two genuinely practical features:

Multi-RU lets a single client be allocated multiple resource units within an OFDMA transmission, making scheduling more efficient for mixed traffic.

Preamble puncturing is the quiet star. Previously, if a single 20 MHz sub-channel within your 160 MHz channel was occupied by a radar exclusion or a neighbour, the whole wide channel became unusable. With puncturing, the AP masks out the affected sub-channel and continues using the rest. In a real building with real neighbours, this recovers a substantial amount of usable spectrum.

Should you deploy Wi-Fi 7 now?

Yes, if you are refreshing anyway, buying for a five-to-seven-year life, deploying in a latency-sensitive environment, or building greenfield with 6 GHz as the primary band.

Not urgently, if your Wi-Fi 6E estate is healthy and your client base is mostly Wi-Fi 5 and Wi-Fi 6. You will pay a premium for capability your clients cannot use.

Watch the power budget. Wi-Fi 7 APs with three radios and a multi-gigabit uplink commonly want 802.3bt. Confirm your switching can deliver it before you commit to the AP count — a mid-project switch replacement is an expensive surprise.

Watch the uplink. A Wi-Fi 7 AP behind a 1 Gbps switch port is a Wi-Fi 7 AP that cannot deliver Wi-Fi 7. Plan for 2.5 GbE at minimum, 5 or 10 GbE for high-density areas.