Wi-Fi CAST

Wi-Fi CAST

Overview

Wi-Fi CAST is a connectionless Wi-Fi communication protocol defined by Realtek. In Wi-Fi CAST, devices can transmit application data without establishing a Wi-Fi connection. It supports one-to-many and many-to-many device connections and communications. Unlike traditional communication methods based on the TCP/IP protocols, Wi-Fi CAST can directly forward data at the data link layer. This design effectively reduces latency caused by packet loss in network congestion scenarios, thereby achieving faster service response.

The following is a comparison diagram between standard Wi-Fi and Wi-Fi CAST communication:

Wi-Fi CAST devices can transmit application data directly, without the need to establish a Wi-Fi connection through a router. This capability enables Wi-Fi CAST to support various networking scenarios, including one-to-one, one-to-many, and many-to-many connections. The illustration below demonstrates these configurations:

Even when devices maintain a standard Wi-Fi connection with a router, they can still use Wi-Fi CAST to communicate with other Wi-Fi CAST nodes, forming a hybrid network, as shown in the figure below:

Wi-Fi CAST uses the CCMP-128 method to protect the security of data frames. Wi-Fi CAST devices maintain several keys, When security is enabled, data frames are encrypted using the CCMP method with the set key.

Advantages

Fast Networking and Low-Latency Communication

There's no need to establish a standard Wi-Fi connection. Application layer data is sent directly to the Wi-Fi driver, greatly improving networking speed and effectively reducing latency.

Low Power Consumption

It supports one-to-many and many-to-many device connections and communication, easily enabling multi-terminal collaboration with good scalability.

Low Latency Response

If the transmitting end has no sending tasks, it can enter a μA-level power consumption mode, greatly improving the battery life of battery-powered products.

Safe and Reliable

CCMP-128 hardware encryption technology is used to protect data frames, ensuring transmission security and reliability.

Typical Applications

Custom Mesh Applications: Take advantage of Wi-Fi CAST's flexible networking and direct data transmission to easily implement custom Wi-Fi Mesh applications.
Remote Debugging: When there is no debug serial port available, Wi-Fi CAST can be used to send core logs to a dedicated Wi-Fi CAST node for analysis.
Remote Control Applications: With low power consumption and fast networking, remote control applications can be easily implemented with higher bandwidth and longer distances.

Custom Mesh Applications

Take advantage of Wi-Fi CAST's flexible networking and direct data transmission to easily implement custom Wi-Fi Mesh applications.

Remote Debugging

When there is no debug serial port available, Wi-Fi CAST can be used to send core logs to a dedicated Wi-Fi CAST node for analysis.

Remote Control Applications

With low power consumption and fast networking, remote control applications can be easily implemented with higher bandwidth and longer distances.

Development Resources

	SDK Download	Link
	Wi-Fi CAST Development Guide	Link
	Wi-Fi CAST Examples	Link
	Contact Us	Link

Recommended ICs

Features	Filter	RTL8721Dx	RTL8720E	RTL8710E	RTL8726E	RTL8713E	RTL8730E	RTL8721F	RTL872xD	RTL8735B
Application Processor	Cortex-M Cortex-A	Cortex-M	Cortex-M	Cortex-M	Cortex-M	Cortex-M	Cortex-A	Cortex-M	Cortex-M	Cortex-M
DSP	Select
ISP?	Select
Arm TrustZone	Select
Dual Band?	Select
Wi-Fi 6	Select
R-MESH?	Select
Ultra-low Power	Select
Ethernet	Select
BT Dual Mode	Select
HMI?	Select
Audio ADC?	Select
Audio DAC?	Select
SDIO Host	Select
SD/EMMC Host	Select
USB	Select
BT Dedicated Antenna?	Select
A2C?	Select