Wi-Fi 6E Improvements over Wi-Fi 6
The Wi-Fi Alliance introduced an update to the existing Wi-Fi 6 certification program called Wi-Fi 6E. Wi-Fi 6E is based on the same IEEE 802.11ax standard as Wi-Fi 6, but adds a number of important features to improve latency and throughput.
- Only available in the 6GHz frequency band
- Legacy protocols (Wi-Fi 4, Wi-Fi 5 and older standards) are not supported
- Congestion reduction changes
- WPA3 and Enhanced Open security only
6GHz band support
The most significant update to Wi-Fi 6E is the addition of 6GHz band support. Consumers can easily identify whether a device supports 6GHz by checking if it is Wi-Fi 6E certified. In the United States, 6GHz band adds an additional 1,200MHz of available spectrum for Wi-Fi. In comparison, 5GHz frequency currently has up to 500MHz of spectrum available. More spectrum means there will be less interference. Along with other improvements to the protocol, Wi-Fi 6E will give users significantly better throughput and lower latency for gaming and other latency-sensitive applications.
Unlike Wi-Fi 6, Wi-Fi 6E is not backwards compatible with previous generations of Wi-Fi standards. This means Wi-Fi 6E is not burdened with past standards which may hinder performance. Wi-Fi 6E product is free to focus on providing the fasted speeds and the most efficient use of the available spectrum using the latest standards.
Prior to Wi-Fi 6, devices share the wireless spectrum using a mechanism called Carrier Sense Multiple Access/Collision Detection (CSMA/CD). This is a polite mechanism where devices are free to use the wireless spectrum until it detects a collision or interference with another device. In CSMA/CD, when a collision is detected, the device will stop using the spectrum, wait a random amount of time and try again. This mechanism worked best when there are not a lot of devices utilizing the wireless spectrum. As Wi-Fi becomes more ubiquitous, CSMA/CD is no longer an effective way to share the wireless spectrum across multiple devices.
Wi-Fi 6 introduced a new mechanism called Orthogonal Frequency Division Multiple Access (OFDMA), which divides the wireless spectrum into small Resource Units (RU) so multiple devices can each have a small slice of the wireless spectrum to themselves and avoid collisions with each other. But because Wi-Fi 6 is also specified to be backwards compatible with legacy standards, it will revert to CSMA/CD when there are legacy devices on the network.
Wi-Fi 6E changes this by eliminating the need to go back to CSMA/CD and only utilizing OFDMA to efficiently handle a large number of devices trying to use the wireless spectrum at the same time.
Congestion reduction changes
Because Wi-Fi 6E doesn’t need to be burdened with legacy protocol compatibility, it can introduce new ways to reduce congestion on the network. When an access point has Multiple Basic Service Set Identifiers (M-BSSID) for purposes such as primary network, backhaul network and guest network, it will traditionally send out beacons for each SSID it hosts. In Wi-Fi 6E, a single beacon will contain the SSID information for each network the access point hosts under a new MBSSID information element (IE). This mechanism greatly cuts down the amount of “chatter” in a network and allows for a cleaner spectrum.
WPA3 and Enhanced Open Security
Similar to how legacy wireless protocols are not supported, Wi-Fi 6E strengthens Wi-Fi security by disallowing legacy security protocols such as WPA and WPA2. In fact, Wi-Fi 6E does not allow a network to be operated without security. WPA3 or Enhanced Open security must be used on a Wi-Fi 6E network. WPA3 introduces Simultaneous Authentication of Equals (SAE) to protect against dictionary attacks to crack the passphrase. Using SAE allows for the use of unique derivation of the Pairwise Master Key (PMK) per client association, so cracking the encryption of one client does not compromise the encryption of another client on the same network. SAE also prevents offline attacks, and offers forward secrecy to the data being exchanged.
Enhanced Open, also known as Opportunistic Wireless Encryption (OWE) works without a password. Enhanced Open does not control access to the network through passphrase authentication, but can help to encrypt the traffic passed between the client and the AP to prevent man in the middle attacks.