Public security network system

The invention discloses a public security network system, and belongs to the technical field of data transmission. According to the system, a virtual private network and a security access platform establish first communication connection by adopting a layer-3 switch, and the security access platform and a public security intranet establish second communication connection by adopting a gap technology; dumb terminal equipment accesses the virtual private network in a dialing connection way, accesses the security access platform through the first communication connection, and finally accesses the public security intranet through the second communication connection; mobile communication equipment or mobile computer equipment establishes a virtual private channel with the virtual private network in the dialing connection way, runs a security authentication program to establish a security authentication channel with the security access platform on the basis of the virtual private channel and the first communication connection, and accesses the public security intranet through the second communication connection; and fixed intelligent equipment accesses the public security intranet in an intercommunication connection way through the public security intranet. The support of a public security network to many kinds of terminal equipment is realized.