Method and apparatus for enhancing security of quantum key distribution network
Provided are a method and an apparatus for enhancing the security of a quantum key distribution network. The quantum key distribution network includes a first node, a second node, and at least one relay node, by means of which the first node and the second node implement a first stage of quantum key distribution; the first node and the second node share a first key pool, which includes at least one key; and the method is executed on either the first node or the second node. The method includes: acquiring a first key obtained after the first stage of quantum key distribution; determining the seed key from the first key pool; generating a first random string by applying, based on the seed key, a first algorithm predetermined with a correspondent node, the first random string having a length equal to that of the first key; and acquiring a second key by performing a preset first bit operation on the first key and the first random string.
1. A method for enhancing security of a quantum key distribution network, wherein the quantum key distribution network comprises a first node, a second node, and at least one relay node, by means of which the first node and the second node implement a first stage of quantum key distribution, the first node and the second node share a first key pool, which comprises at least one key, and the method is executed on the first node and comprises:
acquiring a first key obtained after the first stage of quantum key distribution;
determining a seed key from the first key pool according to information that is released by the second node and corresponds to the seed key; or determining a seed key from the first key pool and then releasing information corresponding to the seed key to the second node;
generating a first random string by applying, based on the seed key, a first algorithm predetermined with the second node, the first random string having a length equal to that of the first key; and
acquiring a second key by performing a preset first bit operation on the first key and the first random string.
2. The method according to claim 1 , wherein the first algorithm is an advanced encryption standard AES key expansion algorithm.
3. The method according to claim 1 , wherein the first random string is a pseudorandom string.
4. The method according to claim 1 , wherein the first bit operation is an Exclusive OR (XOR) operation, or Exclusive NOR (ENOR) operation.
5. The method according to claim 1 , wherein performing the preset first bit operation on the first key and the first random string comprises: performing the preset first bit operation on every certain number of bits in the first key and corresponding bits in the first random string.
6. The method according to claim 1 , wherein the seed key has a length less than that of the first key.
7. The method according to claim 1 , further comprising saving the second key to the first key pool.
8. The method according to claim 1 , wherein the relay node has an upper limit of computing power which is determined based on the first algorithm.
9. The method according to claim 1 , wherein the first node and the second node sharing the first key pool comprises: the first node and the second node each has a local backup of the first key pool; and
determining the seed key from the first key pool comprises: determining the seed key from the local backup of the first key pool.
10. An apparatus for enhancing security of a quantum key distribution quantum key distribution network, wherein the quantum key distribution network comprises a first node, a second node, and at least one relay node, by means of which the first node and the second node implement a first stage of quantum key distribution, the first node and the second node share a first key pool, which comprises at least one key, and the apparatus is implemented on the first node and comprises:
means for acquiring a first key obtained after the first stage of quantum key distribution;
means for determining a seed key from the first key pool according to information that is released by the second node and corresponds to the seed key, or determining a seed key from the first key pool and then releasing information corresponding to the seed key to the second node;
means for generating a first random string by applying, based on the seed key, a first algorithm predetermined with the second node, the first random string having a length equal to that of the first key; and
means for acquiring a second key by performing a preset first bit operation on the first key and the first random string.
11. A computing device, comprising a memory and a processor, wherein the memory stores an executable code, and the processor, when executing the executable code, implements a method for enhancing security of a quantum key distribution network, wherein the quantum key distribution network comprises a first node, a second node, and at least one relay node, by means of which the first node and the second node implement a first stage of quantum key distribution, the first node and the second node share a first key pool, which comprises at least one key, and the method is executed on the first node and comprises:
acquiring a first key obtained after the first stage of quantum key distribution;
determining a seed key from the first key pool according to information that is released by the second node and corresponds to the seed key; or determining a seed key from the first key pool and then releasing information corresponding to the seed key to the second node;
generating a first random string by applying, based on the seed key, a first algorithm predetermined with the second node, the first random string having a length equal to that of the first key; and
acquiring a second key by performing a preset first bit operation on the first key and the first random string.