ETRI This document is an analysis of multiple interfaces in a mobile node using Mobile IPv6 or a mobile router using NEMO Basic Support. The current Mobile IPv6 and NEMO Basic Support are suitable for a single network interface. When a mobile node or a mobile router has multiple interfaces, the current Mobile IPv6 and NEMO Basic Support cannot directly be used for them. In this document, we describe some problems for a mobile node which has multiple network interfaces when the mobile node is using Mobile IPv6 as an aspect of a node.