Fujitsu MBA3147RC Manuel D’Utilisation
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.
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.
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
x
4
+ x
2
+ x + 1