Based on the national natural fundkey project "Intrinsic security optical communication theory and technology research", three prior art solutions for physical layer key distribution are described in detail. In order to achieve high-rate physical layer key distribution compatible with existing communication devices, this paper proposes a physical layer key distribution technology based on fibre channel features. The transmitter and the receiver extract the quantized generation key by using the double-ended loopback measurement bit error rate method based on the fiber channel transmission bit error rate characteristic and key distribution technique. The research results show that the optical fiber transmission rate is 10 Gb/s and the transmission distance is over 200 km. When the physical layer secure key generation rate reaches 400 kb/s, the bit error rate of secure keys does not exceed 2%.