One-time pad encryption in a secure communication network

A secure communication network comprising:

• a plurality of interconnected switches including a source switch, a destination switch, and at least one intermediate switch for at least one packet transferred over the secure communication network from a start node to an end node, wherein:
• the source switch is adapted, upon from the start node receiving each packet of the at least one packet, to replace an original payload of the packet with an encrypted payload that combines the original payload and a respective random pad for the packet, to discard the respective random pad, and to forward the packet with the encrypted payload toward the destination switch via the at least one intermediate switch,
• each of the at least one intermediate switch is adapted to forward each packet of the at least one packet toward the destination switch, and
• the destination switch is adapted, upon from the at least one intermediate switch receiving each packet of the at least one packet, to replace the encrypted payload of the packet with a decrypted payload that combines the encrypted payload and the respective random pad, to discard the respective random pad, and to transmit the packet with the decrypted payload to the end node, with the decrypted payload matching the original payload;
• and
• at least one controller adapted to send the respective random pad for each packet of the at least one packet to the source and destination switches via secure management links, which include a first secure management link between the controller and the source switch and a second secure management link between the controller and the destination switch,
• wherein the at least one packet is a plurality of packets, and for each packet of the packets:
• the source switch is adapted, upon receiving the packet from the start node, to send to the controller a request requesting the respective random pad for the packet via the first secure management link;
• and
• the controller is adapted, upon receiving the request, to generate and send the respective random pad for the packet to the source and destination switches via the secure management links.

A secure communication network comprising:

• a plurality of interconnected switches including a source switch, a destination switch, and at least one intermediate switch for at least one packet transferred over the secure communication network from a start node to an end node, wherein:
• the source switch is adapted, upon from the start node receiving each packet of the at least one packet, to replace an original payload of the packet with an encrypted payload that combines the original payload and a respective random pad for the packet, to discard the respective random pad, and to forward the packet with the encrypted payload toward the destination switch via the at least one intermediate switch,
• each of the at least one intermediate switch is adapted to forward each packet of the at least one packet toward the destination switch, and
• the destination switch is adapted, upon from the at least one intermediate switch receiving each packet of the at least one packet, to replace the encrypted payload of the packet with a decrypted payload that combines the encrypted payload and the respective random pad, to discard the respective random pad, and to transmit the packet with the decrypted payload to the end node, with the decrypted payload matching the original payload;
• and
• at least one controller adapted to send the respective random pad for each packet of the at least one packet to the source and destination switches via secure management links, which include a first secure management link between the controller and the source switch and a second secure management link between the controller and the destination switch,
• wherein the at least one controller is a plurality of controllers including a first and second controller, the first controller and the source switch in a first trust domain securing the first secure management link, and the second controller and the destination switch in a second trust domain securing the second secure management link, and wherein the first controller is adapted to send the respective random pad for each packet of the at least one packet to the second controller via another secure management link between the first and second controllers that passes outside the first and second trust domains.

A method of securing each packet of a plurality of packets transferred over a secure communication network from a start node to an end node, the method comprising:

• receiving the packet from the start node at a source switch;
• sending to a controller a first request in response to the receiving, the first request requesting a respective random pad for the packet via a first secure management link;
• sending the respective random pad for the packet from the controller to the source switch via the first secure management link;
• replacing, by the source switch, an original payload of the packet with an encrypted payload that reversibly combines the original payload and the respective random pad for the packet;
• discarding the respective random pad by the source switch;
• forwarding the packet with the encrypted payload from the source switch to a destination switch via at least one intermediate switch;
• sending to a controller a second request in response to the forwarding, the second request requesting the respective random pad for the packet via a second secure management link;
• sending the respective random pad for the packet from the controller to the destination switch via the second secure management link;
• replacing, by the destination switch, the encrypted payload of the packet with a decrypted payload that combines the encrypted payload and the respective random pad for the packet, wherein the decrypted payload equals the original payload;
• discarding the respective random pad by the destination switch;
• and
• transmitting the packet with the decrypted payload from the destination switch to the end node.