Can Forwarding Loops Appear When Activating iBGP Multipath Load Sharing?
We analyse the possible consequences of activating iBGP multipath load sharing in a given domain (or AS), which allows for load balancing over multiple exit routers. It has been stated that interdomain routing loops may appear in this case. We show that under reasonable assumptions (which reflect commercial relationships between ASes) such routing loops cannot appear. Furthermore we show that even if theses assumptions are not met, routing loops can only be transient.
KeywordsiBGP Multipath Load Sharing Traffic Split Traffic Engineering Forwarding Loops
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