This scheme does not require that Alice and Bob choose between alternative measurements, therefore improving the generating rate of key bits. At the same time, in this scheme detecting Eve requires the comparison of fewer bits.

• 此方案不需要建立密钥的双方Alice、Bob进行测量基的选择，同时，检测偷听者需要对比更少的量子位，所以提高了产生密钥的效率。