Reference Manual
Prox–DU & Prox–SU
www.gemalto.com
DOC118569D
Public Use
Page 140/145
MIFARE
®
Memory Organization
Sector Trailer
The last block of every sector is the sector trailer. It contains the individual secret
authentication Key A, optional Key B and the access condition bits for the blocks of the
particular sector.
Sector Trailer Byte bit 8
MSB
bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1
LSB
Secret Key
0
Authentication Key A
1
2
3
4
5
Access Bits
6
C2
3
C2
2
C2
1
C2
0
C1
3
C1
2
C1
1
C1
0
7
C1
3
C1
2
C1
1
C1
0
C3
3
C3
2
C3
1
C3
0
8
C3
3
C3
2
C3
1
C3
0
C2
3
C2
2
C2
1
C2
0
Data 9
Secret Key
10
Authentication Key B
11
12
13
14
15
CXy: Access bit x for block y
CXy: Complement of CXy
Authentication Keys
Each sector contains a six-byte authentication Key A and a six-byte optional Key B. All
sectors are assigned to the different applications determined by different system providers.
The mutual authentication procedure is performed between the reader/writer and the
contactless card and is driven by the reader/writer. Access to the data stored in a sector is
only possible after a successful authentication.
The secret authentication keys are always read as logical "0". In applications using only one
authentication key, Key A, user can set the access bits where the memory space of the
optional authentication Key B can be used for data storage.
In this case when the authentication key, Key B can no longer be used for authentication,
Summary of Contents for Prox-DU
Page 4: ......
