Avoiding transient loops during IGP convergence in IP networks

— When the topology of an IP network changes due to a link failure or a link weight modification, the routing tables of all the routers must be updated. Each of those updates may cause transient loops. In this paper, we prove that by ordering the updates of the routing tables on the routers, it is possible to avoid all transient loops during the convergence of ISIS or OSPF after a planned link failure, an unplanned failure of a protected link and after a link weight modification. We then propose a protocol that allows the routers to order the update of their routing tables to avoid transient loops whithout requiring any complex computation.

• Type: Conference
• Year: 2005
• Where: INFOCOM
• Authors: Pierre Francois, Olivier Bonaventure
• Keywords: Communications, INFOCOM 2005, Link Weight Modification, Routing Tables, Transient Loops