AS-Level Traceroute

• Main Authors: Jing-He Sun, 孫敬賀
• Other Authors: Wanjiun Liao
• Format: Others
• Language: en_US
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/11530657562329783507

碩士 === 國立臺灣大學 === 電機工程學研究所 === 93 === Traceroute[1] is a network diagnostic tool originally developed by Van Jacobson to identify the IP forwarding path from local host to a destination. This tool is widely used for detecting routing problems, characterizing the end-to-end forwarding path, and discovering the Internet topology. In practice, knowing the Autonomous System (AS) associated with each hop in the forwarding path is also quite valuable. Some of the existing traceroute versions provide additional features including mapping each hop to AS number. Mapping the IP addresses of each hop to origin AS number is the core of displaying the AS forwarding path in the traceroute tool. All existing traceroute tools with AS number mapping look up the origin AS number of each hop along the forwarding path based on the Internet Routing Registry (IRR) database. However, the network operators are not obligate to register and update the information on IRR, the registration information at IRR is incomplete and out-of-date. In this thesis, we develop a new AS-level traceroute tool named AStraceroute to map each hop to its AS number according to the up-to-date public vailable BGP routing tables. Additionally, AStraceroute use TCP SYN to probe hosts for bypassing the firewalls on the path which discards the original traceroute UDP datagrams. Furthermore, our traceroute tool also inference the relationships between each hop, this part is based on the heuristic in [2]. Our work provides a framework for modeling the Internet’s AS-level topology for further research and helps the network operators to make decision on selecting a right upstream AS to connect or peer with.