Wi-Fi Direct is a wireless communication technology based on the Wi-Fi standard and 802.11 networking standard that allows enabled devices to connect with each other directly without requiring a wireless access point or a wireless router and Internet connection. This technology essentially allows the creation of a personal Wi-Fi network for direct communication.
A notable advantage of Wi-Fi Direct is that connection is direct. Although it is based on the same standards used in Wi-Fi or WLAN networks, establishing a connection using this technology does not require an access point or a wireless router and Wi-Fi hotspot. An enabled device is essentially a personal Wi-Fi network. Note that this technology does not require an Internet connection as well. This technology also supports bootstrapping using Near Field Communication or NFC technology.
It is also worth mentioning that this technology is somehow similar to Bluetooth technology. Enabled devices are capable of communicating directly with one another for transferring data, synchronization, and other interfacing purposes. Specific applications include sending and receiving files, displaying information from computers to an enabled display monitor or play media from one device to an output, wireless printing, and play multiplayer games across different devices.
Another notable advantage of Wi-Fi Direct when compared to Bluetooth is that it has a faster data transfer rate. The technology supports a transfer speed of up to 250 Mbps while the current version of Bluetooth has a transfer speed of up to 25 Mbps only. In addition, when compared further to Bluetooth, Wi-Fi Direct has a longer range. It has a maximum theoretical distance of 656 feet while Bluetooth 4.0 has a maximum theoretical distance of 200 feet. These advantages make this technology a more reliable option for sharing large files and data-intensive or bandwidth-critical interfacing.
It is also important to mention that this technology is also backward compatible. Equipped or compatible devices will be able to communicate with legacy Wi-Fi devices or non-Wi-Fi Direct devices. For example, a laptop or smartphone equipped with a Wi-Fi Direct chip can establish a connection with devices such as printers or monitors that have old chips based on wireless local-area networking standards.
Connections established through Wi-Fi Direct are protected by WPA2 security protocol and certification. Also, although connections are direct, a user cannot randomly connect to another enabled device because this wireless technology uses key-based encryption and authentication methods that are similar to Bluetooth technology. Users need to undergo a setup process to establish a connection via this technology. Nonetheless, these features offer substantial security for average users. Take note that equipped or compatible devices in the future will feature WPA3 that provides better security measures than WPA2.
A considerable disadvantage of Wi-Fi Direct, when compared to wired connectivity, is slower transfer speed. Of course, wire-based hardware interfaces such as USB C and Thunderbolt technology offer better and faster data transfer rates than wireless communication technologies. Take note that USB 3.0 has a transfer rate of 640 Mbps while Thunderbolt supports two 10 Gbps channels. It is also important to highlight the fact that the maximum 250 Mbps transfer speed of Wi-Fi Direct is theoretical because it does not take into consideration other factors such as device-specific capabilities and interferences.
Establishing a wireless connection between Wi-Fi Direct devices and even with non-Wi-Fi Direct devices should be hassle-free. However, there are numerous user-reported issues available online claiming problems with connecting two or more enabled devices. These issues seem to be more common in enabled smartphones from different manufacturers and printers. Possibly, these compatibility problems stem from the specific technical implementations of device manufacturers.
The Wi-Fi Alliance noted that Wi-Fi Direct promises energy efficiency through better power management. However, the fact remains that this technology operates in the 2.4 GHz frequency band of the ultra-high frequency or microwave electromagnetic spectrum. Generating this frequency consumes more power than other wireless technologies such as Near Field Communication or Bluetooth Low Energy. Using this technology for an extended period also shortens the battery charge of an enabled device beyond its standard standby and operational times.
Remember that Wi-Fi Direct uses the WPA security and certification protocols to establish and maintain a secure connection. Connecting devices via this technology usually requires entering an eight-digit numerical WPS PIN. However, pin-based authentication method can be subjected to brute force attacks. Some enabled devices have a default PINs that can be exploited easily if users have failed to apply necessary modifications. Hackers can also access the Wi-Fi network and WLAN via the Wi-Fi Direct hardware of vulnerable enabled devices such as printers. These hackers use the connection via Wi-Fi Direct to convince an enabled device to route connection from the local area network.
