1. A method, comprising: receiving, at a device in a computer network, a particular packet associated with a transmission attempts value, the associated transmission attempts value indicative of a first number of times a transmitter has attempted to transmit the particular packet; in response, increasing by one a stored successful attempts value stored at the device, the stored successful attempts value indicative of a second number of times the device has received the same particular packet; and determining a reachability rate of a link from the transmitter to the device based on comparing the associated transmission attempts value to the stored successful attempts value.