The invention discloses a cross-domain
broadcast authentication method in a space information network. The method mainly solves the problems in the prior art that the
authentication efficiency is low, the
extensibility is low and the concurrence of multiple security domains in the space information network is not taken consideration when cross-domain
broadcast authentication is carried out. The realization scheme of the method comprises that in a
system deployment stage, the terminal and agent of each
security domain finish calculating signing work with relatively high costs; in a broadcast
information transmission stage, corresponding signatures only need to be taken out from a pre-calculated signature set; moreover, cross-domain transmission of the broadcast information is finished through the agent of each
security domain, wherein re-signing needs to be carried out each time when
one stage of agent is passed; and finally, a broadcast
receiver finishes information
authentication through the previous signatures. According to the method, through adoption of a pre-calculation mode, the efficiencies of signing and authenticating the
broadcast authentication are greatly improved; moreover, through arrangement of the
security domain agents, under a condition of not relating to the security systems of different security domains, the security transmission and cross-domain
authentication of the broadcast information are ensured.