ISO/IEC 11694-4:2001

Identification cards — Optical memory cards — Linear recording method — Part 4: Logical data structures

Cartes d'identification — Cartes à mémoire optique — Méthode d'enregistrement linéaire — Partie 4: Structures de données logiques

General Information

• Status: Withdrawn
• Publication Date: 31-Oct-2001
• Withdrawal Date: 31-Oct-2001
• ICS: 35.240.15 - Identification cards. Chip cards. Biometrics
• Technical Committee: ISO/IEC JTC 1/SC 17 - Cards and security devices for personal identification
• Drafting Committee: ISO/IEC JTC 1/SC 17 - Cards and security devices for personal identification
• Current Stage: 9599 - Withdrawal of International Standard
• Completion Date: 25-Jun-2008

Relations

• Revised: ISO/IEC 11694-4:2008 - Identification cards — Optical memory cards — Linear recording method — Part 4: Logical data structures
• Effective Date: 15-Apr-2008
• Revises: ISO/IEC 11694-4:1996 - Identification cards — Optical memory cards — Linear recording method — Part 4: Logical data structures
• Effective Date: 15-Apr-2008

Standards Content (Sample)

INTERNATIONAL ISO/IEC
STANDARD 11694-4
Second edition
2001-10-15
Identification cards — Optical memory
cards — Linear recording method —
Part 4:
Logical data structures
Cartes d'identification — Cartes à mémoire optique — Méthode
d'enregistrement linéaire —
Partie 4: Structures de données logiques
Reference number
ISO/IEC 11694-4:2001(E)
©
ISO/IEC 2001

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ISO/IEC 11694-4:2001(E)
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ISO/IEC 11694-4:2001(E)
Contents Page
Foreword.iv
Introduction.v
1 Scope .1
2 Normative references.1
3 Terms and definitions .1
4 Reference points.2
5 Track layout.2
6 Track guides.2
7 Guard tracks.3
8 Data tracks .3
9 Track ID.3
10 Sectors.3
11 Data encoding .3
Annex A (normative) 8-10 NRZI modulation code, PWM recording method .4
Annex B (normative) MFM/NRZI-RZ modulation codes, PPM recording method .28
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ISO/IEC 11694-4:2001(E)
Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical Commission)
form the specialized system for worldwide standardization. National bodies that are members of ISO or IEC
participate in the development of International Standards through technical committees established by the
respective organization to deal with particular fields of technical activity. ISO and IEC technical committees
collaborate in fields of mutual interest. Other international organizations, governmental and non-governmental, in
liaison with ISO and IEC, also take part in the work.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.
In the field of information technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.
Draft International Standards adopted by the joint technical committee are circulated to national bodies for voting.
Publication as an International Standard requires approval by at least 75 % of the national bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this part of ISO/IEC 11694 may be the subject of
patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights.
International Standard ISO/IEC 11694-4 was prepared by Joint Technical Committee ISO/IEC JTC 1, Information
technology, Subcommittee SC 17, Identification cards and related devices.
This second edition cancels and replaces the first edition (ISO/IEC 11694-4:1996), which has been technically
revised.
ISO/IEC 11694 consists of the following parts, under the general title Identification cards — Optical memory cards
— Linear recording method:
 Part 1: Physical characteristics
 Part 2: Dimensions and location of the accessible optical area
 Part 3: Optical properties and characteristics
 Part 4: Logical data structures
Annexes A and B form a normative part of this part of ISO/IEC 11694.
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ISO/IEC 11694-4:2001(E)
Introduction
This part of ISO/IEC 11694 is one of a series of standards describing the parameters for optical memory cards and
the use of such cards for the storage and interchange of digital data.
The standards recognize the existence of different methods for recording and reading information on optical
memory cards, the characteristics of which are specific to the recording method employed. In general, these
different recording methods will not be compatible with each other. Therefore, the standards are structured to
accommodate the inclusion of existing and future recording methods in a consistent manner.
This part of ISO/IEC 11694 is specific to optical memory cards using the linear recording method. Characteristics
which apply to other specific recording methods shall be found in separate standards documents.
This part of ISO/IEC 11694 defines the logical data structures and the extent of compliance with, addition to, and/or
deviation from the relevant base document ISO/IEC 11693.
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INTERNATIONAL STANDARD ISO/IEC 11694-4:2001(E)
Identification cards — Optical memory cards — Linear recording
method —
Part 4:
Logical data structures
1 Scope
This part of ISO/IEC 11694 specifies the logical data structures for optical memory cards necessary to allow
compatibility and interchange between systems using the linear recording method.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of
this part of ISO/IEC 11694. For dated references, subsequent amendments to, or revisions of, any of these
publications do not apply. However, parties to agreements based on this part of ISO/IEC 11694 are encouraged to
investigate the possibility of applying the most recent editions of the normative documents indicated below. For
undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC
maintain registers of currently valid International Standards.
ISO/IEC 11693:2000, Identification cards — Optical memory cards — General characteristics
ISO/IEC 11694-1:2000, Identification cards — Optical memory cards — Linear recording method — Part 1:
Physical characteristics
ISO/IEC 11694-2:2000, Identification cards — Optical memory cards — Linear recording method — Part 2:
Dimensions and location of the accessible optical area
ISO/IEC 11694-3:2001, Identification cards — Optical memory cards — Linear recording method — Part 3: Optical
properties and characteristics
3 Terms and definitions
For the purposes of this part of ISO/IEC 11694, the terms and definitions given in ISO/IEC 11693,
ISO/IEC 11694-1, ISO/IEC 11694-2, ISO/IEC 11694-3 and the following apply.
3.1
data bit
area which represents data on an optical memory card; mark which has a different reflectivity and/or phase
difference from the background reflectivity
NOTE One mark can define one or two data transitions dependent on the modulation method selected.
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ISO/IEC 11694-4:2001(E)
3.2
data track
area located between adjacent track guides where data are written and/or read
3.3
error correction code (ECC)
code designed to correct certain kinds of errors in data
3.4
error detection and correction (EDAC)
family of methods in which redundancy is added to a message block, at the time the message block is recorded, in
known fashion; upon read back, a decoder removes the redundancy and uses the redundant information to detect
and correct erroneous channel symbols
3.5
modulation code
system for coding which transforms information bits into some physical representation for recording onto the optical
memory card
3.6
pitch
distance between corresponding points on adjacent data spots
3.7
sector
minimum unit of data that can be accessed on a card for any read and/or write command
4 Reference points
The reference track and reference edges defined in ISO/IEC 11694-2 apply unless otherwise specified.
4.1 First data bit
The first data bit shall be located on the reference track and is part of the track ID. The location may vary
dependent on the track layout selected. See annex A or annex B.
5 Track layout
Track layout information shall be preformatted on cards during manufacture and/or written to cards prior to use.
The total number of tracks may vary dependent on the application requirements; however, in all cases, tracks shall
be arranged in order, and numbered sequentially, beginning with the reference track. See annex A or annex B for
actual track layouts and numbering sequences.
5.1 Track layout options
See annex A or annex B for information concerning data structures that support the optional card layouts described
in ISO/IEC 11694-2.
6 Track guides
Track guides shall be uniformly spaced across the card and shall extend the length of the accessible optical area.
The accumulated tolerances across the width of all track guides shall be less than or equal to 0,01 % at 25 °C. See
annex A or annex B for specific dimensions.
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ISO/IEC 11694-4:2001(E)
7 Guard tracks
There shall be 20 guard tracks, ten located directly above and ten directly below the user data area to enable the
optics to locate the user data tracks and prevent the optical head from overrunning the accessible optical area if
auto-tracking is lost.
Guard tracks may contain data relating to card type, physical data format, specific application and/or card drive
autodiagnosis and calibration. See annex A or annex B.
8 Data tracks
Written and/or preformatted data shall be located within data tracks and centred between adjacent track guides to a
tolerance of ± 0,5µm in the y-axis. See annex A or annex B.
9 Track ID
Written and/or preformatted track ID shall identify the physical address of each data track. See annex A or annex B
for specific configuration and location.
10 Sectors
Sectors are defined by the amount of user data in bytes and the number of sectors which can be written to a single
data track. See annex A or annex B for specific types/sizes.
All sectors within a given track shall be identical in type and partially written tracks shall only be appended with
sectors of the same type as those previously written on the track unless otherwise specified in annex A or annex B.
NOTE Sector types/sizes have been defined to maximize the efficiency of data storage on a track and may vary by
modulation code.
11 Data encoding
To encode data requires the use of a modulation code. See annex A or annex B for acceptable modulation codes.
NOTE The user data on any single optical card shall only be encoded using one modulation code.
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ISO/IEC 11694-4:2001(E)
Annex A
(normative)
8-10 NRZI modulation code, PWM recording method
A.1 Scope
This annex defines the logical data structures specific to optical cards using a pulse width modulation recording
method and an 8-10 NRZI modulation code.
A.2 Terms and definitions
For the purposes of this annex, the following terms and definitions apply.
A.2.1
carrier/burst modulation code
form of FM modulation code which makes 1,0 information correspond to a different frequency
A.2.2
NRZI
non-return-to-zero-inverse; a specific modulation method to make 1 corresponding to inverse and 0 to non-inverse
A.2.3
Reed-Solomon code
byte error detection and/or correction code which is generally used in optical and magnetic storage
A.3 Reference points
The first bottom guard track (LPT9) is the reference track and shall be located 5,4 mm ± 0,3 mm from the horizontal
reference edge.
NOTE This dimension is tighter yet still falls within the tolerance range specified by dimension D of ISO/IEC 11694-2.
A.3.1 First data bit
The first data bit closest to the left edge of the card shall be located at 12,50 mm ± 0,40 mm in the x-axis. The
distance between the first data bit closest to the left edge of the card and the first data bit closest to the right edge
of the card shall be 60,6 mm ± 0,1 mm in the x-axis.
A.4 Track layout
Tracks shall be arranged in order beginning with the reference track and shall be numbered sequentially beginning
with track -10, the reference track.
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ISO/IEC 11694-4:2001(E)
Track Description Track No. Hex
Guard track LPT9 (first bottom)
-10 FFF6
:: :
:: :
Guard track LPT0(last bottom) -1 FFFF
First user data track 0 0000
::
::
Last user data track n
Guard track UPT0 (first top) n+1
::
::
Guard track UPT9 (last top) n+10
NOTE Because the total number of tracks may vary dependent on the application requirements, the last user data track
and the top guard tracks are expressed in parametric form.
A.5 Track layout examples
This section provides information concerning data structures that support the optional card layouts described in
ISO/IEC 11694-2.
A.5.1 Cards with moderate data capacity
This layout shall contain 2520 data tracks, of which 2500 shall be user data tracks. Tracks shall be numbered
sequentially beginning with track -10, the reference track.
NOTE This layout supports the inclusion of a magnetic stripe and/or signature panel.
A.5.2 Cards with small data capacity
This layout shall contain 1128 data tracks, of which 1108 shall be user data tracks. Tracks shall be numbered
sequentially beginning with track -10, the reference track.
NOTE This layout supports the inclusion of a magnetic stripe, IC chip with contacts, embossing and/or signature panel.
A.5.3 Cards with maximum data capacity
This layout shall contain 3593 data tracks, of which 3573 shall be user data tracks. Tracks shall be numbered
sequentially beginning with track −10, the reference track.
NOTE This layout supports the inclusion of a magnetic stripe and/or signature panel.
A.6 Track guides
The width of the track guides shall be 2,3µm ± 0,3µm. The distance from the centre of one track guide to the
centre of an adjacent track guide shall be 12,0µm ± 0,2µm.
No track guides shall have any breaks exceeding 180µm.
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ISO/IEC 11694-4:2001(E)
A.7 Guard tracks
All guard tracks shall contain preformatted track-ID and card-type data and/or card-ID field data. Cards shall not be
issued with these tracks left blank nor shall these tracks be made available to the application for writing.
Each guard track shall contain two track ID areas, one to the left, the other to the right of the card-type data and/or
card-ID field. See A.10.
NOTE It is expected that card drive units will have the ability to read guard tracks whether preformatted with card-type data
or pre-recorded with card-ID field data.
A.7.1 Card-type data
Card-type data are pre-set indicia that denote the physical data format, the number and location of tracks and/or a
specific type application. There shall be two blocks per track each containing the same card-type pattern repeated
eight times. See Figure A.1 and Table A1.
Card-type data shall be preformatted using a carrier/burst modulation code. These tracks shall not be made
available to the application for writing nor shall cards be issued with these tracks left blank.
The carrier/burst pattern shall consist of an L-pattern (denotes 0 data) and an S-pattern (denotes 1 data), the only
difference between patterns being the pattern-pitch. The L-pattern pitch shall be 240µm ± 5µm and the S-pattern
pitch shall be 120µm ± 5µm. See A.12.2, Figure A.1 and Table A.1.
The length, or x-axis dimension, of preformatted data bits shall be 6,0µm ± 0,6µm; the width, or y-axis dimension,
shall be 2,5µm ± 0,5µm; the bit pitch shall be 12,0µm ± 0,3µm.SeeFigure A.1.
The distance between the first data bit of the left track ID closest to the left edge of the card and the first data bit of
the card type pattern closest to the left edge of the card shall be 14,9 mm ± 0,1 mm in the x-axis.
A.7.2 Unique card identification (ID) field
For those applications requiring unique card serialization, guard tracks LPT1 (track -2) and LPT0 (track -1) shall be
used as a card-ID field. If using this option, information related to the application and other issuer information may
be included in these tracks along with the card serialization data.
Card-ID field data shall be pre-recorded during the manufacturing process. These tracks shall not be made
available to the application for writing nor shall cards be issued with these tracks left blank.
There are two types of card identification (ID) field data described in A.7.2.1.1 (card-type 0 to 14) and A.7.2.1.2
(card-type 15).
A.7.2.1 Content
Figure A.2 shows the structure and data content of the card-ID field. Data shall be pre-recorded using a type-2
sector as defined in A.11.1 and Table A.2. The same information shall be repeated in each sector of each track,
that is four times in two tracks.
NOTE 1 It is not permissible to set all data fields to 0FF hex.
NOTE 2 If no components of the card-ID field are used, these two tracks must be preformatted with card-type data. See
A.7.1.
Field components are described in both A.7.2.1.1 and A.7.2.1.2.
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ISO/IEC 11694-4:2001(E)
A.7.2.1.1 Card-type 0 to 14
 Application identifier (AID): The AID shall consist of 16 bytes of alpha/numeric data, which data shall be
agreed to by the card manufacturer and card issuer. If the AID is not implemented, these 16 bytes shall be
set to 0FF hex.
NOTE Card manufacturers shall have the responsibility to manage the information to ensure AID's are not duplicated
between different card issuers.
 Unique identifier (UID): The UID shall consist of six bytes, one byte containing the card manufacturer

identifier (CMID), and five bytes containing a unique card identifier (UCID). If the UID is not implemented,
these six bytes shall be set to 0FF hex.
NOTE 1 The card manufacturer shall have the responsibility to ensure only one UID is contained in their card products.
NOTE 2 Since different card manufacturers can use the same UCID, it is recommended that the entire UID (CMID +
UCID) be used.
 Number of issuer data bytes (NID): The NID shall consist of two bytes which specify the number of bytes
used in the ISSUER portion of the card-ID field. If the NID is not implemented, these two bytes shall be set to
0FF hex.
 Optional issuer data (ISSUER): The ISSUER shall consist of 488 bytes and shall be reserved for the

exclusive use of the card issuer. Any unused bytes in this area shall be set to 0FF hex.
NOTE Since card-ID field data are pre-recorded, the ISSUER data must be pre-recorded at the time of card
manufacture.
A.7.2.1.2 Card-type 15
 Application identifier (AID): Same with A.7.2.1.1.

 Unique identifier (UID): Same with A.7.2.1.1.
 Number of issuer data bytes (NID): Same with A.7.2.1.1.
 Format identifier (FID): The FID shall consist of six bytes of alpha/numeric data, which specify the format
classification. "SIOC01" shall be recorded for the current international standard.
 Card type (CTYPE): The CTYPE shall be one byte data which is same with the card-type data. In this case,
it shall be 0F hex.
 Track pitch (PITCH): The PITCH shall be one byte data, which is ten-times value of track pitch. For 12 µm
track pitch, it shall be 78 hex.
 Number of user track (NUMBER): The NUMBER shall consist of two bytes which specify the user track

number in the card. It shall be recorded the most significant byte first.
 Mediatype(MTYPE): The MTYPE shall be one byte which specifies the media type which is under control
of the card manufacturer.
 Contacts for IC chip (CONTACT): The CONTACT shall be one byte which specifies the presence/absence
of contacts for IC chip. This byte is optional, and 0FF hex shall be recorded in no use.
00 hex : No IC contacts
10 hex : Contacts on the same side with AOA (Accessible Optical Area)
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ISO/IEC 11694-4:2001(E)
20 hex : Contacts on the opposite side with AOA
others : Reserved
 Contactless IC chip (CLIC): The CLIC shall be one byte which specifies the presence/absence of
contactless IC chip. This byte is optional, and 0FF hex shall be recorded in no use.
00 hex : No IC chip
10 hex : Includes inductive coupling IC chip
20 hex : Includes capacitive coupling IC chip
others : Reserved
 Magneticstripe(MS): The MS shall be one byte which specifies the presence/absence of magnetic stripe.
This byte is optional, and 0FF hex shall be recorded in no use.
00 hex : No magnetic stripe
10 hex : Magnetic stripe on the same side with AOA
20 hex : Magnetic stripe on the opposite side with AOA
30 hex : Magnetic stripe on both sides
others : Reserved
 Embossing (EMBOSS): The EMBOSS shall be one byte which specifies the presence/absence of

embossing. This byte is optional, and 0FF hex shall be recorded in no use.
00 hex : No embossing
10 hex : With embossing
others : Reserved
 Optional issuer data (ISSUER): The ISSUER shall consist of 472 bytes and shall be reserved for the
exclusive use of the card issuer. Any unused bytes in this area shall be set to 0FF hex.
NOTE Since card-ID field data are pre-recorded, the ISSUER data must be pre-recorded at the time of card
manufacture.
A.8 Data tracks
Each data track can contain a maximum of 60,7 mm of written and/or preformatted data, including the gaps
between sectors.
A.8.1 Data bits
Use of the 8-10 NRZI modulation code requires that written and/or preformatted data bits consist of four different
sizes. The length, or x-axis dimension, shall be 3,0µm ± 0,6µm, 6,0µm ± 0,6µm, 9,0µm ± 0,6µm or
12,0µm ± 0,6µm; the width, or y-axis dimension, shall be 2,5µm ± 0,5µm.
The minimum distance from the centre of one data bit to the centre of an adjacent data bit shall be
6,0µm ± 0,3µm.
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ISO/IEC 11694-4:2001(E)
A.9 Track components
A.9.1 Preamble (PRE)
A series of 60 consecutive bits laid out from the left edge direction of the card. The PRE bit-pattern shall be
1010101010. or 0101010101. See Figure A.3.
NOTE The PRE generates the data clock required by the card drive's phase-lock-loop (PLL) circuit when an optical card is
read from left to right.
A.9.2 Sync marker
A specific 10-bit pattern which does not show up as a read-output signal when the 8-10 NRZI modulation code is
implemented on the track ID and/or user data.
NOTE When asynchronization occurs during reading, data can be re-synchronized after sensing successive sync markers.
The sync marker shall be set on the border of the data matrix, created when implementing the Reed-Solomon
code, to divide the user data into multiple blocks. See Figure A.4.
The first sync marker from the left edge of the card, in every sector and in both track ID's, shall be 1100010001
prior to NRZI modulation. All other sync markers shall be either 1100010001 or 0100010001 prior to NRZI
modulation.
Thus all written sync markers shall become either 1000011110 or 0111100001 after NRZI modulation.
A.9.3 Post-amble (PST)
A series of 60 consecutive bits laid out from the left edge direction of the card. The PST bit-pattern shall be
0101010101. or 1010101010. See Figure A.3.
NOTE The PST generates the data clock required by the card drive's PLL circuit when an optical card is read from right to
left.
A.10 Track ID
Track ID shall be preformatted at the right and left side of each data track. See Figures A.3 and A.5.
NOTE The structure allows the track ID to be read from either direction, that is from left to right or right to left.
A.10.1 Content
The track ID shall consist of 75 bytes of information and the length shall be 2,25 mm ± 0,02 mm. The track ID shall
consist of the PRE, sync markers, track numbers, ECC and the PST. See A.12.3 and Figure A.3.
The track number itself shall be repeated twice per track ID with the most significant bit (MSB) positioned closest to
the left edge of the card.
A.11 Sectors
Every sector shall contain a PRE, sync markers, user data, ECC and a PST and shall be separated from adjoining
sectors by a gap, that is an unrecorded area. See Figures A.4 and A.5.
User data shall be written within a sector and arranged from left to right regardless of the writing direction
implemented.
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ISO/IEC 11694-4:2001(E)
NOTE Sectors can be written in either direction, that is, from left to right, the forward direction, or from right to left, the
reverse direction.
The accumulated tolerances across any sector shall be less than ± 3 % of the sector length.
A.11.1 Types of sectors
Sector types shall be as defined in Figure A.6 and Table A.2.
NOTE The sector lengths shown in Figure A.6 are the maximum allowed when taking into consideration up to a 3 %
deviation in the velocity of the card drive mechanism which is anticipated in the actual use of optical card systems.
All sectors, regardless of sector type, shall be located relative to the first bit position of the left track ID. The MSB
shall always be placed at the edge of each sector closest the left edge of the card.
A.12 Data encoding
This section describes the method for encoding and storing data on optical cards using the various sector types.
A.12.1 Modulated data
All track ID's and user data along with their associated ECC shall be modulated using the 8-10 NRZI modulation
code. See Figures A.7, A.8, A.9 and Table A.3.
NOTE When encoding, ten bits are assigned to every eight bits of actual data using the 8-10 modulation table. When
reading, the original eight bits are retrieved/demodulated from the corresponding 10-bit data pattern.
A.12.2 Carrier/burst modulation code
All card-type data shall be preformatted using the carrier/burst modulation code. See A.7.1, Figure A.1 and
Table A.1.
NOTE In the read mode, this modulation code permits card-type information found in the guard tracks to be demodulated
with software, eliminating the influence from the variable velocity, if any, of the optical card drive.
A.12.3 Error correction code
Each track ID and every sector of written data shall be encoded using the Reed-Solomon ECC generated by the
following generator polynomial:
3 2
G(x) = (X - α )(X- α )(X- α)(X-1)
where
8 4 3 2
x +x +x +x +1 = 0
8
α is a primitive element of GF (2 ).
The Reed-Solomon code arranges every track ID and every sector of user data into a matrix as shown in
Figure A.10 and then applies the ECC based on the generator polynomial, resulting in the addition of four parity
bytes to the matrix.
EXAMPLE 1 Track ID are encoded using a C1 (6,2), C2 (5,1) Reed-Solomon code. As a result, 28 parity bytes are added to
the original two bytes which make up the track ID.
EXAMPLE 2 Encoding a sector type 7 using the Reed-Solomon ECC.
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ISO/IEC 11694-4:2001(E)
Write 16 bytes of data containing the following integer values in hexadecimal:
00 01 02
...