IP mobility in mobile telecommunications system

摘要

The present invention relates to arranging data transmission for a mobile node in a telecommunications system comprising a secure network and an insecure network. A connection to a secure network for a mobile node may be arranged by a home agent if the mobile node is accessing the secure network directly or via a third network other than the insecure network, or a connection to the secure network may be arranged by a VPN node if the mobile node is accessing the secure network via the insecure network. According to a first aspect of the invention, the VPN node and the home agent are configured to allocate the same IP address as an internal IP address and as a home address.