List of Certificates the group holds - Selected certificates
are presented in a bitmap format.
Receiving order is as:
OCTET 1 OCTET 2 .....
xxxxxxxx xxxxxxxx .....
|| || |_ Cert 9
|| ||
|| ||___ Cert 4
|| |____ Cert 3
|| . . .
||_________ Cert 2
|__________ Cert 1
where x : 1 - The represented certficate is selected
0 - The represented certificate is not selected.