Quantum key distribution method and device, and storage medium

Abstract

This application discloses quantum key distribution methods and devices, and storage media. In an implementation, an ith node generates, based on a determined first quantum key corresponding to the ith node on a target routing path and a determined second quantum key corresponding to the ith node on the target routing path, a third quantum key corresponding to the ith node on the target routing path, and sends the third quantum key corresponding to the ith node on the target routing path to a destination node on the target routing path, or encrypts a received first ciphertext by using the third quantum key corresponding to the ith node on the target routing path, and sends an obtained second ciphertext corresponding to the ith node to an (i+1)th node on the target routing path.

1 . A method for quantum key distribution, comprising:
 determining, by an i th  node on a target routing path of N routing paths, a first quantum key corresponding to the i th  node, wherein the first quantum key is obtained by the i th  node for sharing between the i th  node and an (i−1) th  node on the target routing path;   determining, by the i th  node, a second quantum key corresponding to the i th  node, wherein the second quantum key corresponding to the i th  node on the target routing path is obtained by the i th  node for sharing between the i th  node and an (i+1) th  node on the target routing path;   generating, by the i th  node based on the first quantum key corresponding to the i th  node and the second quantum key corresponding to the i th  node, a third quantum key corresponding to the i th  node on the target routing path; and   sending, by the i th  node, the third quantum key corresponding to the i th  node to a destination node on the target routing path or a second ciphertext corresponding to the i th  node to a (i+1) th  node on the target routing path, wherein the second ciphertext is encrypted by the i th  node by using the third quantum key based on a first ciphertext received from the (i−1)  th  node.   
     
     
         2 . The method according to  claim 1 , wherein each node of the target routing path has a corresponding first quantum key and a corresponding second quantum key, a second quantum key corresponding to the (i−1) th  node is same as the first quantum key corresponding to the i th  node, and the second quantum key corresponding to the i th  node is same as a first quantum key corresponding to the (i+1) th  node. 
     
     
         3 . The method according to  claim 1 , wherein N is greater than 1, wherein a first quantum key corresponding to the i th  node on a first routing path is different from a first quantum key corresponding to the i th  node on a second routing path, and wherein the first routing path and the second routing path are in the N routing paths passing through the i th  node. 
     
     
         4 . The method according to  claim 1 , wherein the first quantum key corresponding to the i th  node is determined based on: (1) indication information received by the i th  node from a centralized controller or the (i−1) th  node, or (2) network topology information of a quantum communication system and a first preset rule. 
     
     
         5 . The method according to  claim 4 , wherein the first quantum key is further determined based on a ranking of the N routing paths passing through the i th  node, and wherein the ranking of the N routing paths is determined by the i th  node based on one or more of (1) a ranking relationship between N index numbers of the (i−1) th  node on the N routing paths, (2) a ranking relationship between the N index numbers of the (i+1) th  node on the N routing paths, and (3) a ranking relationship between N index numbers of the N routing paths. 
     
     
         6 . The method according to  claim 1 , wherein the second quantum key corresponding to the i th  node is determined based on: (1) indication information received by the i th  node from a centralized controller or the (i+1) th  node, or (2) network topology information of a quantum communication system and a second preset rule. 
     
     
         7 . The method according to  claim 6 , wherein the second quantum key is further determined based on a ranking of W routing paths passing through the i th  node and the (i+1) th  node, and wherein the ranking of the W routing paths is determined by the i th  node based on one or more of (1) a ranking relationship between W index numbers of W routing paths, (2) a ranking of the W routing paths, and (3) a ranking relationship between W index numbers of an (i+2) th  node on W routing paths. 
     
     
         8 . The method according to  claim 1 , wherein the first ciphertext is encrypted by using the third quantum key based on a first algorithm that satisfies:
 g(f E (K i−1, i−2 (L j ), K i−1, i (L j )), f E (K i, i−1 (L j ), K i, i+1 (L j )))=f E (K i'1, i−2 (L j ), K i, i+1 (L j )), wherein   L j  is an identifier of the target routing path;   K i−1, i−2 (L j ) is a first quantum key corresponding to the (i−1) th  node on the target routing path L j ;   K i−1, i (L j ) is the second quantum key corresponding to the (i−1) th  node on the target routing path L j ;   K i, i−1 (L j ) is the first quantum key corresponding to the i th  node on the target routing path L j ;   K i, i+1 (L j ) is the second quantum key corresponding to the i th  node on the target routing path L j ;   f E (⋅) is a function corresponding to a second algorithm used when the third quantum key is generated; and   g(⋅) is a function corresponding to the first algorithm.   
     
     
         9 . A device for quantum key distribution, comprising:
 at least one processor; and   a memory coupled to the at least one processor and storing programming instructions for execution by the at least one processor, the programming instructions instruct the device to perform operations comprising:   determining, by an i th  node on a target routing path of N routing paths, a first quantum key corresponding to the i th  node, wherein the first quantum key is obtained by the i th  node for sharing between the i th  node and an (i−1) th  node on the target routing path;   determining, by the i th  node, a second quantum key corresponding to the i th  node, wherein the second quantum key corresponding to the i th  node on the target routing path is obtained by the i th  node for sharing between the i th  node and an (i+1) th  node on the target routing path;   generating, by the i th  node based on the first quantum key corresponding to the i th  node and the second quantum key corresponding to the i th  node, a third quantum key corresponding to the i th  node on the target routing path; and   sending, by the i th  node, the third quantum key corresponding to the i th  node to a destination node on the target routing path or a second ciphertext corresponding to the i th  node to a (i+1) th  node on the target routing path, wherein the second ciphertext is encrypted by the i th  node by using the third quantum key based on a first ciphertext received from the (i−1) th  node.   
     
     
         10 . The device according to  claim 9 , wherein each node of the target routing path has a corresponding first quantum key and a corresponding second quantum key, a second quantum key corresponding to the (i−1) th  node is same as the first quantum key corresponding to the i th  node, and the second quantum key corresponding to the i th  node is same as a first quantum key corresponding to the (i+1) th  node. 
     
     
         11 . The device according to  claim 9 , wherein N is greater than 1, wherein a first quantum key corresponding to the i th  node on a first routing path is different from a first quantum key corresponding to the i th  node on a second routing path, and wherein the first routing path and the second routing path are in the N routing paths passing through the i th  node. 
     
     
         12 . The device according to  claim 9 , wherein the first quantum key corresponding to the i th  node is determined based on: (1) indication information received by the i th  node from a centralized controller or the (i−1) th  node, or (2) network topology information of a quantum communication system and a first preset rule. 
     
     
         13 . The device according to  claim 12 , wherein the first quantum key is further determined based on a ranking of the N routing paths passing through the i th  node, and wherein the ranking of the N routing paths is determined by the i th  node based on one or more of (1) a ranking relationship between N index numbers of the (i−1) th  node on the N routing paths, (2) a ranking relationship between the N index numbers of the (i+1) th  node on the N routing paths, and (3) a ranking relationship between N index numbers of the N routing paths. 
     
     
         14 . The device according to  claim 9 , wherein the second quantum key corresponding to the i th  node is determined based on: (1) indication information received by the i th  node from a centralized controller or the (i+1) th  node, or (2) network topology information of a quantum communication system and a second preset rule. 
     
     
         15 . The device according to  claim 14 , wherein the second quantum key is further determined based on a ranking of W routing paths passing through the i th  node and the (i+1) th  node, and wherein the ranking of the W routing paths is determined by the i th  node based on one or more of (1) a ranking relationship between W index numbers of W routing paths, (2) a ranking of the W routing paths, and (3) a ranking relationship between W index numbers of an (i+2) th  node on W routing paths. 
     
     
         16 . The device according to  claim 9 , wherein the first ciphertext is encrypted by using the third quantum key based on a first algorithm that satisfies:
 g(f E (K i'1, i−2 (L j ), K i−1, i (L j )), f E (K i, i−1 (L j ), K i, i+1 (L j )))=f E (K i−1, i−2 (L j ), K i, i+1 (L j )), wherein   L j  is an identifier of the target routing path;   K i−1, i−2 (L j ) is a first quantum key corresponding to the (i−1) th  node on the target routing path L j ;   K i−1, i (L j ) is the second quantum key corresponding to the (i−1) th  node on the target routing path L j ,   K i, i−1 (L j ) is the first quantum key corresponding to the i th  node on the target routing path L j ;   K i, i+1 (L j ) is the second quantum key corresponding to the i th  node on the target routing path L j ;   f E (⋅) is a function corresponding to a second algorithm used when the third quantum key is generated; and   g(⋅) is a function corresponding to the first algorithm.   
     
     
         17 . A non-transitory computer-readable medium storing one or more instructions executable by at least one processor to perform operations comprising:
 determining, by an i th  node on a target routing path of N routing paths, a first quantum key corresponding to the i th  node, wherein the first quantum key is obtained by the i th  node for sharing between the i th  node and an (i−1) th  node on the target routing path;   determining, by the i th  node, a second quantum key corresponding to the i th  node, wherein the second quantum key corresponding to the i th  node on the target routing path is obtained by the i th  node for sharing between the i th  node and an (i+1) th  node on the target routing path;   generating, by the i th  node based on the first quantum key corresponding to the i th  node and the second quantum key corresponding to the i th  node, a third quantum key corresponding to the i th  node on the target routing path; and   sending, by the i th  node, the third quantum key corresponding to the i th  node to a destination node on the target routing path or a second ciphertext corresponding to the i th  node to a (i+1) th  node on the target routing path, wherein the second ciphertext is encrypted by the i th  node by using the third quantum key based on a first ciphertext received from the (i−1) th  node.   
     
     
         18 . The non-transitory computer-readable medium according to  claim 17 , wherein each node of the target routing path has a corresponding first quantum key and a corresponding second quantum key, a second quantum key corresponding to the (i−1) th  node is same as the first quantum key corresponding to the i th  node, and the second quantum key corresponding to the i th  node is same as a first quantum key corresponding to the (i+1) th  node. 
     
     
         19 . The non-transitory computer-readable medium according to  claim 17 , wherein N is greater than 1, wherein a first quantum key corresponding to the i th  node on a first routing path is different from a first quantum key corresponding to the i th  node on a second routing path, and wherein the first routing path and the second routing path are in the N routing paths passing through the i th  node. 
     
     
         20 . The non-transitory computer-readable medium according to  claim 17 , wherein the first quantum key corresponding to the i th  node is determined based on: (1) indication information received by the i th  node from a centralized controller or the (i−1) th  node, or (2) network topology information of a quantum communication system and a first preset rule.