Patent ID: 7408853

Claim:
A reproduction-only recording medium wherein blocks having a main data area and a linking area are continuous with each other to form a data track by embossed pits, the data track being divided into 32-bit physical sector numbers; and main data recorded in said main data area and linking data recorded in said linking area in each of said blocks are scrambled by a random sequence scrambling data of 8-bit scrambling bytes generated by an identical system including a 16-bit shift register being loaded with an initial value and generating the 8-bit scrambling bytes by taking an initial eight bits in the shift register as a first scrambling byte and performing an eight bit shift to generate subsequent scrambling bytes from the initial eight bits of the shift register, wherein a 15-bit cluster number in at least one of the 32-bit physical sector numbers in the data track and a bit of value 1 is preset as the initial value when said main data and linking data are scrambled by the random sequence.