1. A computer-implemented method, comprising: identifying a first routing path of two or more routing paths for a packet to travel from a first node to a second node through a mesh network, wherein the first node receives a link status of the second node through the first routing path; estimating a first time period needed to transmit the packet via the first routing path; identifying a second routing path of the two or more routing paths, wherein the first node receives the link status of the second node through the second routing path; estimating a second time period needed to transmit the packet via the second routing path; normalizing the first and the second time periods by a regression analysis to generate a first and a second normalized expected transmission time (normalized ETT) value, wherein the regression analysis generates the first and the second normalized ETT values using an exponential function as the regression model; comparing the first normalized ETT value with the second normalized ETT value; determining a routing path as the one of the first routing path and the second routing path with the lower of the first normalized ETT value and the second normalized ETT value; and transmitting the packet to the second node through the routing path.