The development and description of the PRB protocol as well as analysis of guessing the seed for PRNG (Secs. I and II and Appendix B) were supported by the grant of the Russian Science Foundation (RSF), Project No. 17-71-20146. The security analysis against the intercept-resend attack (Secs. III-V and Appendices A and C) was supported by the grant of the President of the Russian Federation (Project No. MK- 2815.2017.1).