Reverse LG is a fully online service for determination of the reverse AS paths for the given autonomous system.
It may not be a secret that reverse path determination often turns out to be a difficult, if not impossible task -- only a small number of companies provide public Looking Glass services. The functionality represented on this page is a result of modeling all levels of BGP decision-making process plus prefix announcement policies. During this modeling we employ the information on the reverse-engineered routing policies of all potentially related AS.
We use different sources for data collection such as RIPE and Routeviews. However, without the knowledge about peering relations between your AS and other parties the quality of the modeling will be rather low. Hence, it’s necessary for you to establish BGP multihop session with our reflector and provide us Full View.
This service gives you an opportunity not only to determine BGP path for current routing policy but also evaluate the effect of altering the prepend policy on the choice of the path for certain AS. You can enable multiple AS while using the service.