The study of the Internet topology allows us to discover properties that can be beneficial to the performances of network protocols and applications. Thus, Internet mapping is very useful to simulation software focusing on network protocols. Unfortunately Internet mapping has two major drawbacks. First it takes a lot of time to be carried out and second it is often incomplete. To solve these two problems, we have developed a fast mapping software whose aim is to map the heart of the Internet as fast as possible with the highest attainable precision. In this paper, we describe our software and evaluate its performances compared to an existing and freely available mapping software. We assess the completeness of the router level maps by creating overlays with an autonomous system topology. We also assess its use inIpv6 and the evolution of its performances inIpv4 when increasing the size of the input parameter set. We conclude with a detailed study on the delay of the paths and links in the Internet.