Arrangement for establishing a bidirectional tunnel between a mobile router and a correspondent node

A method in a mobile router configured for sending packets output from a local node to a correspondent node, the method comprising:

• sending a query, via a tunnel terminated by a home agent, to a route server resource having a prescribed security association with the home agent, the query requesting identification of a correspondent router for the correspondent node;
• receiving a reply, via the tunnel terminated by the home agent, that specifies the correspondent router and at least an address prefix for the correspondent node;
• sending a binding update request to the correspondent router via a unidirectional tunnel to the correspondent router, the binding update request specifying a corresponding home address for the mobile router, a corresponding care-of address for the mobile router, and a mobile router flag specifying that the binding update request was generated by a router that is mobile;
• validating for the correspondent router that the home address is reachable via the care-of address;
• and
• establishing a bidirectional tunnel with the correspondent router based on receiving an acknowledgment to the binding update request from the correspondent router.

A computer readable medium having stored thereon sequences of instructions for sending packets, having been output by a correspondent node, for delivery to a mobile router by an Internet Protocol (IP) based router, the sequences of instructions including instructions for performing the steps of:

• receiving a binding update request from the mobile router, the binding update request specifying a home address for the mobile router, a care-of address for the mobile router, and a mobile router flag specifying that the binding update was generated by a mobile router;
• selectively establishing a bidirectional tunnel to the mobile router by entering the binding update request in a binding cache entry, indicating the home address is reached by the care-of address, based on verifying that the home address is reachable via the care-of address;
• and
• updating a routing table to specify that at least one identified address prefix served by the mobile router is reachable via the home address.

A computer readable medium having stored thereon sequences of instructions for sending packets, having been output from a local node, for delivery to a correspondent node by an Internet Protocol (IP) based mobile router, the sequences of instructions including instructions for performing the steps of:

• sending a query, via a tunnel terminated by a home agent, to a route server resource having a prescribed security association with the home agent, the query requesting identification of a correspondent router for the correspondent node;
• receiving a reply, via the tunnel terminated by the home agent, that specifies the correspondent router and at least an address prefix for the correspondent node;
• sending a binding update request to the correspondent router via a unidirectional tunnel to the correspondent router, the binding update request specifying a corresponding home address for the mobile router, a corresponding care-of address for the mobile router, and a mobile router flag specifying that the binding update request was generated by a router that is mobile;
• validating for the correspondent router that the home address is reachable via the care-of address;
• and
• establishing a bidirectional tunnel with the correspondent router based on receiving an acknowledgment to the binding update request from the correspondent router.

An Internet Protocol (IP) based router configured for sending packets output from a correspondent node for delivery to a mobile router, the router comprising:

• means for receiving a binding update request from the mobile router, the binding update request specifying a home address for the mobile router, a care-of address for the mobile router, and a mobile router flag specifying that the binding update was generated by a mobile router;
• means for selectively establishing a bidirectional tunnel to the mobile router by entering the binding update request in a binding cache entry, indicating the home address is reached by the care-of address, based on verifying that the home address is reachable via the care-of address;
• and
• means for updating a routing table to specify that at least one identified address prefix served by the mobile router is reachable via the home address.

A mobile router configured for sending packets output from a local node to a correspondent node, the mobile router comprising:

• means for sending a query, via a tunnel terminated by a home agent, to a route server resource having a prescribed security association with the home agent, the query requesting identification of a correspondent router for the correspondent node, the means for sending including:
• (1) means for receiving a reply, via the tunnel terminated by the home agent, that specifies the correspondent router and at least an address prefix for the correspondent node,
• (2) means for sending a binding update request to the correspondent router via a unidirectional tunnel to the correspondent router, the binding update request specifying a corresponding home address for the mobile router, a corresponding care-of address for the mobile router, and a mobile router flag specifying that the binding update request was generated by a router that is mobile,
• (3) means for validating for the correspondent router that the home address is reachable via the care-of address;
• and
• means for establishing a bidirectional tunnel with the correspondent router based on receiving an acknowledgment to the-binding update request from the correspondent router.