Lightweight and robust cross-domain identity authentication method based on master-slave block chain

The invention discloses a lightweight and robust cross-domain identity authentication method based on a master-slave block chain, and the method comprises the steps: dividing a whole block chain into a master block chain and a plurality of slave block chains, and enabling a cross-domain communication node to be responsible for the information interaction between the master block chain and the slave chains; and performing function matching on nodes with different functions in trust domains of different systems in a master-slave chain. Due to the decentration characteristic of the block chain, the centralized risk can be reduced, then local consensus different from previous whole chain consensus is used, data consensus sharing can be completed only by performing consensus on authentication related slave chains and main chains, the slave chains store specific certificates, and the main chains store hash values of the certificates, so that the number of consensus participating nodes is effectively reduced, and th