SAS Interface
30 C141-C013
1.2.2 Hashed SAS address SSP frames include a hashed version of the SAS address to provide an additional
level of verification of proper frame routing.
The code used for the hashing algorithm is a cyclic binary Bose, Chaudhuri, and
Hocquenghem (BCH) (63, 39, 9) codes. Table 1.2 lists the parameters for the
code.
Table 1.2 Hashed SAS address code parameter
Parameter Value
Number of bits per codeword 63
Number of data bits 39
Number of redundant bits 24
Minimum distance of the code 9
The generator polynomial for this code is:
G(x) = (x 6 + x + 1) (x 6 + x 4 + x 2 + x + 1) (x 6 + x 5 + x 2 + x + 1) (x 6 + x 3 + 1)
After multiplication of the factors, the generator polynomial is:
G(x) = x 24 + x 23 + x 22 + x 20 + x 19 + x 17 + x 16 + x 13 + x 10 + x 9 + x 8 + x 6 + x 5
+
x 4 + x 2 + x + 1