Design and Performance Evaluation of a Distributed OFDMA-Based MAC Protocol for MANETs

Table 1

The types of logical errors (𝑋: a node requesting a reservation of a PDU bin and 𝑌: a node receiving a resource reservation request from 𝑋).

	Cause	Detection method	Actions on detection
LET1	When 𝑋 selects a PDU bin 𝑖 for reservation, it could not know 𝑈𝑌.	Inspecting 𝑈𝑌.	𝑌 sends a CTS frame with error type LET1. 𝑋 restarts the reservation process.
LET2	Multiple node pairs attempt to reserve the same PDU bin using different RTS channels at the same time.	𝑌 checks the RTS region of the frame from which it receives a resource reservation request.	𝑌 sends a CTS frame with error type LET2. 𝑋 restarts the reservation process.
LET3	Multiple nodes send RTS frames simultaneously to the same node 𝑌 through different RTS channels to reserve the same PDU bin.	𝑌 checks the RTS region of the frame from which it receives resource reservation requests.	𝑌 randomly selects a winner and assigns another PDU bin to a loser. If 𝑋 is a loser, it uses the assigned PDU bin if it is available. If not, it restarts the reservation process.