Bitwise Operation-Based In-Network Processing for Loss Tomography

Network tomography is an inference technique for internal network characteristics such as link loss rate and link delay from end-toend measurements. In this paper, we consider network tomography for link loss rates, which is referred to as loss tomography. We propose a loss tomography scheme with bitwise operation-based in-network processing. Intermediate nodes generate coded packets by performing bitwise-operations on received packets so as to embed information about paths along which those packets have been transmitted. The coded packets are then forwarded to downstream nodes. In this way, receiver nodes obtain information about paths along which packets are transmitted successfully. Moreover, we show a recursion to compute the likelihood function of path loss rates, which can be utilized in estimating link loss rates from path loss information. key words: network tomography, link loss rates, in-network processing, likelihood function