Method and apparatus for protecting the routing of data packets

An apparatus in a DNS server system for protecting the routing of data packets in a packet data network along a transmission path with routers between a first sending end-host and a second receiving end host, comprising:

• a master key manager adapted to distribute a master key to said routers in the packet data network for encryption of destination addresses in data packets,
• an address query manager adapted to receive an address query from the first end-host regarding the second end-host,
• a host database for storing destination addresses associated with end-hosts, adapted to provide a destination address of the second end-host for said address query, and
• an encryption unit adapted to encrypt said destination address by using a key dependent on said master key, and to create a destination parameter containing the encrypted destination address, wherein the address query manager is further adapted
• to send the created destination parameter to the first end-host in response to the address query, thereby enabling the first end-host to get across data packets to the second end-host by attaching the destination parameter to each transmitted data packet, and enabling the routers to decrypt the encrypted destination address in the data packets from the first end-host using a key dependent on the distributed master key, and
• to perform a forwarding operation based on the decrypted destination address and a new encrypted destination address being attached to a forwarded packet to determine an outgoing port for the packet.

A method of protecting the routing of data packets in a packet data network along a transmission path with routers between a first sending end-host and a second receiving end-host, comprising the following steps performed by a router in said transmission path of the packet data network:

• receiving a data packet,
• attempting to decrypt a destination address in the received data packet using a key dependent on a master key which has been distributed from a DN8 server system for encryption of destination addresses in data packets,
• admitting the packet if a destination parameter including a valid destination address can be derived from the packet by decryption, and discarding the packet if no such destination parameter can be derived from the packet by decryption,
• performing a forwarding operation based on the decrypted destination address to determine an outgoing port for the packet,
• encrypting the destination address using said key dependent on the master key, and creating a new destination parameter for the packet including the newly encrypted destination address, and
• sending the packet to a next hop node from the determined outgoing port with the created new destination parameter attached to the packet.