Clear-to-send (CTS) is an 802.11 control message that grants permission to transmit a frame. It helps coordinate access to the wireless medium and reduce collisions. section 19.1.3
In the RTS/CTS mechanism, a device first sends request-to-send (RTS); CTS grants permission, allowing the requested data transmission to proceed. The exchange reduces collisions but adds overhead. section 19.1.3
Key operational facts:
- CTS belongs to the 802.11 control-frame category, alongside RTS and acknowledgment (Ack) messages. section 19.1.3
- Using RTS/CTS adds two extra frames for each data frame, reducing network efficiency; modern networks usually avoid it. section 19.1.3
- Ack serves a different role: it confirms delivery, and missing acknowledgments trigger retransmission. section 19.1.3
