Abstract: A system and method are provided for proactively buffering quantum key distribution (QKD) key material. The method includes monitoring key generation rates and surpluses at QKD devices at each node of a QKD link in a QKD network, retrieving surplus key material from the QKD devices at one or both nodes of the QKD link, and buffering the surplus key material in a local storage at one or both nodes in the QKD link. The surplus key material can be used to offset overhead introduced in securely relaying keys between non-adjacent demand pairs in the QKD network. The surplus key material can also be used to offset future transient decreases in key generation rates.

Abstract: A system and method are described for proactively performing key swaps among nodes in a quantum key distribution (QKD) network. The method includes determining a routing solution for nodes in the QKD network; making the routing solution available to the nodes in the QKD network; and initiating key swaps among the nodes in the QKD network according to the routing solution, prior to key requests being made within the QKD network. The method can also include continuously performing key swaps among the nodes in the QKD network according to the routing solution; detecting a change in capacity and/or a change in demand on one or more links within the QKD network; determining a new routing solution based on the detected change; and continuously preforming subsequent key swaps according to the new routing solution.

Abstract: A system and method are provided for proactively buffering quantum key distribution (QKD) key material. The method includes monitoring key generation rates and surpluses at QKD devices at each node of a QKD link in a QKD network, retrieving surplus key material from the QKD devices at one or both nodes of the QKD link, and buffering the surplus key material in a local storage at one or both nodes in the QKD link. The surplus key material can be used to offset overhead introduced in securely relaying keys between non-adjacent demand pairs in the QKD network. The surplus key material can also be used to offset future transient decreases in key generation rates.

Abstract: A system and method are described for proactively performing key swaps among nodes in a quantum key distribution (QKD) network. The method includes determining a routing solution for nodes in the QKD network; making the routing solution available to the nodes in the QKD network; and initiating key swaps among the nodes in the QKD network according to the routing solution, prior to key requests being made within the QKD network. The method can also include continuously performing key swaps among the nodes in the QKD network according to the routing solution; detecting a change in capacity and/or a change in demand on one or more links within the QKD network; determining a new routing solution based on the detected change; and continuously preforming subsequent key swaps according to the new routing solution.

Abstract: A method and system for quantum key distribution (QKD) between a first location and a second location through an intermediate location. The system and method include executing a quantum phase between each of the first and second locations and the intermediate location to determine a first location raw data string at the first location, a first-intermediate raw data string at the intermediate location, a second location raw data string at the second location, and a second-intermediate raw data string at the intermediate location, respectively; calculating, at the intermediate location, announcement data based on a function of the first and second-intermediate raw data strings; announcing, at the intermediary location, the announcement data over a classical channel; and deriving, at each of the first and second locations, a secret key based on the available data and on communications between the first and second locations via a classical channel.

Abstract: A method and system for quantum key distribution (QKD) between a first location and a second location through an intermediate location. The system and method include executing a quantum phase between each of the first and second locations and the intermediate location to determine a first location raw data string at the first location, a first-intermediate raw data string at the intermediate location, a second location raw data string at the second location, and a second-intermediate raw data string at the intermediate location, respectively; calculating, at the intermediate location, announcement data based on a function of the first and second-intermediate raw data strings; announcing, at the intermediary location, the announcement data over a classical channel; and deriving, at each of the first and second locations, a secret key based on the available data and on communications between the first and second locations via a classical channel.