Reputation-based routing and error-correction coding in ad hoc networks

A method for monitoring a relay node in an ad hoc wireless network of nodes, wherein the monitoring is performed by a monitor node, comprising the steps:

• determining an erasure rate by counting packets received and transmitted by the relay node;
• determining a delay between the corresponding packets received and transmitted;
• determining an error rate by comparing the corresponding packets received and transmitted;
• determining a channel reliability by monitoring data rates of the received and transmitted packets;
• and
• combining the erasure rate, the delay, the error rate, and the channel reliability to determine a reputation of the relay node, and wherein the packets are encoded with a low-density parity check (LDPC) code, wherein the receiving and the transmitting of the packets is a forwarding process expressed by an equivalent channel model of malicious behavior of the relay node, wherein the equivalent channel model includes in order a first fading channel based on the channel reliability of the received packets, a delay channel based on the delay, an erasure channel based on the erasure rate, an error channel based on the error rate, and a second fading channel based on the reliability of the transmitted packets, wherein the erasure rate is ε, the delay is τ, the error rate is ρ, the channel reliability is θ, and reliability is σ, and an expected time resource consumption for the forwarding process is based on a τ-symbol delay occurring in the delay channel, a 1/(1−ε)N-symbol delay occurring in the erasure channel because a channel capacity of a binary erasure channel is 1−ε, and a 1/(1−H(ρ))N-symbol delay occurring in the error channel because the channel capacity of a binary symmetric channel (BSC) is 1−H(ρ), where N and H(.) denote an average bit length of the packets, and a binary entropy function H(ρ)=−ρ log(ρ)−(1−ρ) log(1−ρ), respectively.