ISO/IEC 7811-7:2014

Identification cards — Recording technique — Part 7: Magnetic stripe — High coercivity, high density

ISO/IEC 7811-7:2014 is one of a series of International Standards describing the characteristics for identification cards as defined in the definitions clause and the use of such cards for international interchange. It specifies requirements for a high coercivity magnetic stripe (including any protective overlay) on an identification card and encoding technique. It takes into consideration both human and machine aspects and states minimum requirements. Coercivity influences many of the quantities specified in ISO/IEC 7811-7:2014 but is not itself specified. The main characteristic of the high coercivity magnetic stripe is its improved resistance to erasure. This is achieved with minimal probability of damage to other magnetic stripes by contact while retaining read compatibility with magnetic stripes as defined in ISO/IEC 7811‑2. ISO/IEC 7811-7:2014 provides for a card capacity of approximately 10 times that of a card conforming to ISO/IEC 7811‑6. The number of tracks has been increased to six, each track being approximately half the width of tracks conforming to ISO/IEC 7811‑6, located so that readers designed to read these high density tracks will also be able to read cards conforming to ISO/IEC 7811‑2 and ISO/IEC 7811‑6. Data is encoded in 8 bit bytes using the MFM encoding technique. Data framing is used to limit error propagation and error correction techniques further improve reliability of reading. It is the purpose of this series of International Standards to provide criteria to which cards shall perform. No consideration is given within these International Standards to the amount of use, if any, experienced by the card prior to test. Failure to conform to specified criteria should be negotiated between the involved parties. ISO/IEC 10373‑2 specifies the test procedures used to check cards against the parameters specified in ISO/IEC 7811-7:2014.

Cartes d'identification — Technique d'enregistrement — Partie 7: Bandeau magnétique — Haute coercitivité, haute densité

General Information

• Status: Withdrawn
• Publication Date: 24-Aug-2014
• Withdrawal Date: 24-Aug-2014
• 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/WG 1 - Physical characteristics and test methods for ID-cards
• Current Stage: 9599 - Withdrawal of International Standard
• Completion Date: 07-Aug-2018

Relations

• Revised: ISO/IEC 7811-7:2018 - Identification cards — Recording technique — Part 7: Magnetic stripe: High coercivity, high density
• Effective Date: 29-Apr-2017
• Revises: ISO/IEC 7811-7:2004 - Identification cards — Recording technique — Part 7: Magnetic stripe — High coercivity, high density
• Effective Date: 10-May-2012

Standards Content (Sample)

INTERNATIONAL ISO/IEC
STANDARD 7811-7
Second edition
2014-09-01
Identification cards — Recording
technique —
Part 7:
Magnetic stripe — High coercivity,
high density
Cartes d’identification — Technique d’enregistrement —
Partie 7: Bandeau magnétique — Haute coercitivité, haute densité
Reference number
ISO/IEC 7811-7:2014(E)
©
ISO/IEC 2014

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ISO/IEC 7811-7:2014(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO/IEC 2014
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior
written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of
the requester.
ISO copyright office
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Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail [e-mail]
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Published in Switzerland
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ISO/IEC 7811-7:2014(E)

Contents Page
Foreword .iv
1 Scope .1
2 Conformance .1
3 Normative references .1
4 Terms and definitions . 2
5 Physical characteristics of the identification card . 4
5.1 Magnetic stripe area warpage. 4
5.2 Surface distortions . 4
6 Physical characteristics of the magnetic stripe .5
6.1 Height and surface profile of the magnetic stripe area . 5
6.2 Surface roughness . 7
6.3 Adhesion of stripe to card . 7
6.4 Wear of magnetic stripe from read/write head . 7
6.5 Resistance to chemicals . 8
7 Performance characteristics for the magnetic material .8
7.1 General . 8
7.2 Testing and operating environment . 8
7.3 Signal amplitude requirements for magnetic media . 8
8 Encoding technique .10
9 Encoding specification.11
9.1 Angle of recording .11
9.2 Nominal bit density .12
9.3 Flux transition spacing variation .12
9.4 Signal amplitude requirements .12
9.5 Bit configuration .12
9.6 Direction of recording .13
9.7 Leading and trailing clock bits.13
10 Data structure .13
10.1 Track format .13
10.2 Coding for error detection and correction .15
11 Decoding .18
12 Location of encoded tracks .19
Annex A (informative) Compatibility of magnetic stripes (ISO/IEC 7811-6 and ISO/IEC 7811-7) .20
Annex B (informative) Magnetic stripe abrasivity .21
Annex C (informative) Static magnetic characteristics .22
Annex D (informative) Reed-Solomon code references .25
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ISO/IEC 7811-7:2014(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. In the field of information technology, ISO and IEC have established a joint technical committee,
ISO/IEC JTC 1.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for
the different types of document should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject
of patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights.
Details of any patent rights identified during the development of the document will be in the Introduction
and/or on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the meaning of ISO specific terms and expressions related to conformity
assessment, as well as information about ISO’s adherence to the WTO principles in the Technical Barriers
to Trade (TBT) see the following URL: Foreword - Supplementary information
The committee responsible for this document is Joint Technical Committee ISO/IEC JTC 1, Information
technology, Subcommittee SC 17, Cards and personal identification.
This second edition cancels and replaces the first edition (ISO/IEC 7811-7:2004) of which it constitutes
a major revision with the following changes.
— The primary standard cards held by Q-Card are used to calibrate the manufacture of secondary
reference cards. Other primary standard cards held by PTB and Card testing International (CTI) are
used as backup to replace cards held by Q-Card as they wear out.
— Delete reference to character sets in the Scope since none are used in this International Standard.
— List of major differences has been moved from the Introduction to Annex A.
— The supplier of secondary reference cards has changed from PTB to Q-Card.
ISO/IEC 7811 consists of the following parts, under the general title Identification cards — Recording
technique:
— Part 1: Embossing
— Part 2: Magnetic stripe — Low coercivity
— Part 6: Magnetic stripe — High coercivity
— Part 7: Magnetic stripe — High coercivity, high density
— Part 8: Magnetic stripe — High coercivity of 51,7 kA/m (650 Oe)
— Part 9: Tactile identifier mark
Notes in this International Standard are only used for giving additional information intended to assist in
the understanding or use of the International Standard and do not contain provisions or requirements to
which it is necessary to conform in order to be able to claim compliance with this International Standard.
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INTERNATIONAL STANDARD ISO/IEC 7811-7:2014(E)
Identification cards — Recording technique —
Part 7:
Magnetic stripe — High coercivity, high density
1 Scope
This part of ISO/IEC 7811 is one of a series of International Standards describing the characteristics
for identification cards as defined in the definitions clause and the use of such cards for international
interchange.
This part of ISO/IEC 7811 specifies requirements for a high coercivity magnetic stripe (including any
protective overlay) on an identification card and encoding technique. It takes into consideration both
human and machine aspects and states minimum requirements.
Coercivity influences many of the quantities specified in this part of ISO/IEC 7811 but is not itself
specified. The main characteristic of the high coercivity magnetic stripe is its improved resistance to
erasure. This is achieved with minimal probability of damage to other magnetic stripes by contact while
retaining read compatibility with magnetic stripes as defined in ISO/IEC 7811-2.
This standard provides for a card capacity of approximately 10 times that of a card conforming to
ISO/IEC 7811-6. The number of tracks has been increased to six, each track being approximately half
the width of tracks conforming to ISO/IEC 7811-6, located so that readers designed to read these high
density tracks will also be able to read cards conforming to ISO/IEC 7811-2 and ISO/IEC 7811-6. Data is
encoded in 8 bit bytes using the MFM encoding technique. Data framing is used to limit error propagation
and error correction techniques further improve reliability of reading.
It is the purpose of this series of International Standards to provide criteria to which cards shall perform.
No consideration is given within these International Standards to the amount of use, if any, experienced
by the card prior to test. Failure to conform to specified criteria should be negotiated between the
involved parties.
ISO/IEC 10373-2 specifies the test procedures used to check cards against the parameters specified in
this part of ISO/IEC 7811.
NOTE Numeric values in the SI and/or Imperial measurement system in this part of ISO/IEC 7811 might
have been rounded off and therefore are consistent with, but not exactly equal to, each other. Either system can
be used, but the two should not be intermixed or reconverted. The original design was made using the Imperial
measurement system.
2 Conformance
A prerequisite for conformance with this part of ISO/IEC 7811 is conformance with ISO/IEC 7810.
An identification card is in conformance with this part of ISO/IEC 7811 if it meets all mandatory
requirements specified herein. Default values apply if no others are specified.
3 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
ISO/IEC 4287-1, Surface roughness — Terminology — Part 1: Surface and its parameters
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ISO/IEC 7811-7:2014(E)

ISO/IEC 7810, Identification cards — Physical characteristics
ISO/IEC 10373-1, Identification cards — Test methods — Part 1: General characteristics
ISO/IEC 10373-2, Identification cards — Test methods — Part 2: Cards with magnetic stripes
4 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/IEC 7810 and the following
apply.
4.1
primary standard
set of reference cards established by Physikalisch-Technische Bundesanstalt (PTB) and maintained by
PTB, Q-Card, and WG1 secretariat that represent the values of UR and IR designated RM7811-6
4.2
secondary standard
reference card designated RM7811-6 that is related to the primary standard as stated in the calibration
certificate supplied with each card
Note 1 to entry: Secondary standards can be ordered from Q-Card, 301 Reagan St., Sunbury, PA 17801, USA. The
source of secondary standards will be maintained at least until 2018.
4.3
unused un-encoded card
card possessing all the components required for its intended purpose, which has not been subjected
to any personalization or testing operation, and which has been stored in a clean environment with no
more than 48 h exposure to day-light at temperatures between 5 °C to 30 °C and humidity between 10 %
to 90 % without experiencing thermal shock
4.4
unused encoded card
card according to 4.3 that has only been encoded with all the data required for its intended purpose (e.g.
magnetic encoding, embossing, electronic encoding)
4.5
returned card
card according to 4.4 after it has been issued to the card holder and returned for the purpose of testing
4.6
flux transition
location of the greatest rate of change with distance of the magnetization
4.7
reference current
I
R
minimum recorded current amplitude under the given test conditions that causes, on the reference card,
a readback signal amplitude equal to 80 % of the reference signal amplitude U , at a density of 20 flux
R
transitions per mm (508 flux transitions per inch) as shown in Figure 6
4.8
reference flux level
F
R
flux level in the test head that corresponds to the reference current I
R
4.9
test recording currents
two recording currents defined by: I = recording current corresponding to 2,2 F and I = recording
min R max
current corresponding to 2,5 F
R
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ISO/IEC 7811-7:2014(E)

4.10
individual signal amplitude
U
i
base-to-peak amplitude of a single readback voltage signal
4.11
average signal amplitude
U
A
sum of the absolute values of the amplitude of each signal peak (U ) divided by the number of signal
i
peaks (n) for a given track over the length of the magnetic stripe area
4.12
reference signal amplitude
U
R
maximum value of the average signal amplitude of a reference card corrected to the primary standard
4.13
physical recording density
number of flux transitions per unit length recorded on a track
4.14
bit density
number of data bits stored per unit of length (bits/mm or bpi)
4.15
bit cell
distance for a data bit nominally the reciprocal of the bit density (see Figure 8)
4.16
average bit cell
B
a
product of bit cell length and sum of the actual distances for all flux transition intervals on a track
divided by the sum of the nominal distances for all flux transition intervals on the track
4.17
local average bit cell
B
a6
comparison reference for a given flux transition interval equal to the nominal L1 distance multiplied by
the sum of the actual distances for the previous six flux transition intervals divided by the sum of the
nominal distances for the previous six flux transition intervals
L1 × (Σ actual)/(Σ nominal)
4.18
demagnetization current
I
d
D C current value that reduces the average signal amplitude to 80 % of the reference signal amplitude
(U ) on a secondary reference card that has been encoded at a density of 40 ft/mm (1 016 ftpi) at a
R
current of I
min
4.19
L
1
short distance between adjacent flux transitions nominally equal to 1 times the bit cell
4.20
L
2
medium distance between adjacent flux transitions nominally equal to 1,5 times the bit cell
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ISO/IEC 7811-7:2014(E)

4.21
L
3
long distance between adjacent flux transitions nominally equal to 2 times the bit cell
4.22
FSC
frame synchronization character
4.23
CRC
cyclic redundancy check
4.24
CP
column parity
4.25
U
F
magnitude of the individual element at 20 flux transitions per mm frequency of the Fourier spectrum for
a given track over the length of the magnetic stripe area
5 Physical characteristics of the identification card
The identification card shall conform to the specification given in ISO/IEC 7810.
WARNING — The attention of card issuers is drawn to the fact that information held on the
magnetic stripe may be rendered ineffective through contamination by contact with dirt and
certain commonly used chemicals including plasticizers. It should also be noted that any printing
or screening placed on top of the magnetic stripe must not impair the function of the magnetic
stripe.
5.1 Magnetic stripe area warpage
Application of a 2,2 N (0.5 lbf) load evenly distributed on the front face opposite the magnetic stripe
shall bring the entire stripe within 0,08 mm (0.003 in) of the rigid plate.
5.2 Surface distortions
There shall be no surface distortions, irregularities or raised areas on both the front and the back of the
card in the area shown in Figure 1 that might interfere with the contact between the magnetic head and
magnetic stripe.
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ISO/IEC 7811-7:2014(E)

2,54 (0.100)
maximum
Top reference edge
Distortion-free
area
19,05 (0.750)
minimum
Figure 1 — Distortion-free area on card with magnetic stripe
If a raised signature panel area is located on the front or back of the card, then it shall be no closer to the
top edge of the card than 19,05 mm (0.750 in).
NOTE Raised areas and distortions on other areas of the card may cause card transport problems with
magnetic stripe processing equipment resulting in reading or writing errors.
6 Physical characteristics of the magnetic stripe
6.1 Height and surface profile of the magnetic stripe area
The magnetic stripe area is located on the back of the card as shown in Figure 2.
5,54 (0 .218 )
ma x
To p re fe re nce edg e
Minimu m m agnetic M agnetic stripe ar ea a
stripe width (W)
Figure 2 — Location of magnetic material
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ISO/IEC 7811-7:2014(E)

6.1.1 Surface profile of the magnetic stripe area
The maximum vertical deviation (a) of the transverse surface profile of the magnetic stripe area is
shown below. See Figures 3, 4 and 5. The slope of the surface profile curve shall be limited to: -4a/W <
slope < 4a/W.
When the bending stiffness value (see ISO/IEC 7810) for the card is 20 mm or more then the surface
profile limits are:
Minimum stripe width As shown in Figure 3A As shown in Figure 3B
W = 6,35 mm (0,25 in) a ≤ 9,5 μm (375 μin) a ≤ 5,8 μm (225 μin)
W = 10,28 mm (0,405 in) a ≤ 15,4 μm (607 μin) a ≤ 9,3 μm (365 μin)
When the bending stiffness value (see ISO/IEC 7810) for the card is less than 20 mm then the surface
profile limits are:
Minimum stripe width As shown in Figure 3A As shown in Figure 3B
W = 6,35 mm (0,25 in) a ≤ 7,3 μm (288 μin) a ≤ 4,5 μm (175 μin)
W = 10,28 mm (0.405 in) a ≤ 11,7 μm (466 μin) a ≤ 7,3 μm (284 μin)
W
W
a
a
Figure 3 — Surface profile
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ISO/IEC 7811-7:2014(E)

Ab ru pt dr op
Pe rm itte d No t pe rm itte d
Figure 4 — Surface profile examples
Figure 5 — Irregular surface profile examples
6.1.2 Height of the magnetic stripe area
The vertical deviation (h) of the magnetic stripe area relative to the adjacent surface of the card shall be:
-0,005 mm ( - 200 µin) ≤ h ≤ 0,038 mm (1500 µin)
Spiking in the profile caused by the material “squirt out” in hot stamping is not part of the stripe. It shall
not extend above the magnetic stripe area height (h) as defined above.
6.2 Surface roughness
The average surface roughness (R ) of the magnetic stripe area shall not exceed 0,40 µm (15.9 µin) in
a
both the longitudinal and transverse directions. Refer to ISO/IEC 4287 Part 1.
6.3 Adhesion of stripe to card
The stripe shall not separate from the card under normal use.
6.4 Wear of magnetic stripe from read/write head
Average signal amplitude (U ) and individual signal amplitude (U ) are measured before and after 2 000
A i
wear cycles and shall result in:
U ≥ 0,60 U and U ≥ 0,80 U
A after A before i after A after
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ISO/IEC 7811-7:2014(E)

6.5 Resistance to chemicals
Average signal amplitude (U ) and individual signal amplitude (U ) are measured before and after short
A i
term exposure (as defined in the referenced Test Method document) shall result in:
U ≥ 0,90 U and U ≥ 0,90 U
A after A before i after A after
Average signal amplitude (U ) and individual signal amplitude (U ) are measured before and after long
A i
term exposure (24 hours) to acid and alkaline artificial perspiration, as defined in the referenced Test
Method document.
U ≥ 0,90 U and U ≥ 0,90 U
A after A before i after A after
7 Performance characteristics for the magnetic material
The purpose of this section is to enable magnetic interchangeability between card and processing
systems. Media coercivity is not specified. The media’s performance criteria, regardless of coercivity, is
specified in clause 7.3.
7.1 General
This method uses a reference card whose material is traceable to the primary standard (see Clause
4). All signal amplitude results from the use of the secondary reference card must be corrected by the
factor supplied with the secondary reference card.
7.2 Testing and operating environment
The testing environment for signal amplitude measurements is 23 °C ± 3 °C (73 °F ± 5 °F) and 40 % to
60 % relative humidity. When tested under otherwise identical conditions, the average signal amplitude
measured at 40 ft/mm (1 016 ftpi) shall not deviate from its value in the above test environment by
more than 15 % after 5 minute exposure over the following operating environment range:
temperature -35 °C to 50 °C (-31 °F to 122 °F)
relative humidity 5 % to 95 %
7.3 Signal amplitude requirements for magnetic media
The requirements for recording characteristics of the card are shown in Table 1, and Figures 6 and 7.
The media’s performance requirements specified in section 7.3 shall be met in order to achieve improved
resistance to erasure, and to enable magnetic interchange between card and processing systems. The
properties in Annex C are intended as guidelines for magnetic material. Annex C is informative and shall
not be used as performance criteria for cards.
Table 1 — Signal amplitude requirements for unused unencoded cards
Description Density Test recording cur- Signal amplitude Requirement
ft/mm (ftpi) rent result
Signal amplitude 20 (508) I U 0,8 U ≤ U ≤ 1,2 U
min A1 R A1 R
Signal amplitude 20 (508) I U U ≤ 1,26 U
min i1 i1 R
Signal amplitude 20 (508) I U U ≥ 0,8 U
max A2 A2 R
The slope of the saturation curve shall never be positive between I and I .
min max
It is not permissible to combine the above requirements mathematically.
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ISO/IEC 7811-7:2014(E)

Table 1 (continued)
Description Density Test recording cur- Signal amplitude Requirement
ft/mm (ftpi) rent result
Signal amplitude 40 (1016) I U U ≥ 0,65 U
max i2 i2 R
Resolution 40 (1016) I U U ≥ 0,8 U
max A3 A3 A2
Erasure 0 I , DC U U ≤ 0,03 U
min A4 A4 R
Extra pulse 0 I , DC U U ≤ 0,05 U
min i4 i4 R
Demagnetisation 0 I , DC U U ≥ 0,64 U
d A5 A5 R
Demagnetisation 0 I , DC U U ≥ 0,54 U
d i5 i5 R
Overwrite 20 (508) I U U ≤ 0,03 U
max F6 F7 F6
40 (1016) I U
min F7
The slope of the saturation curve shall never be positive between I and I .
min max
It is not permissible to combine the above requirements mathematically.
NOTE 1 The density of 20 ftpmm converts to 508 ftpi in this standard and to 500 ftpi in ISO/IEC 7811 part 2
and part 6. These 2 are not different in principle. To ensure compatibility at the higher recording density the more
accurate conversion is used in this part of the standard.
NOTE 2 It has been observed that low resolution as measured per Table 1 can correlate with high flux transition
spacing variation as measured per Table 2.
U
A1
130
U
A2
120
Re ad ba ck
vo lt ag e
100
U
R
(%U )
R
80
60
40
20
Key
example curve
reference card curve corrected to the primary standard
Figure 6 — Saturation curve example showing tolerance area
NOTE The curve defines the primary standard response (on a card). The window parameters define a card
that will be functional in the machine readable environment.
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ISO/IEC 7811-7:2014(E)

lux tra ns itio ns lux tra ns itio ns
base line
Figure 7 — Waveform example
8 Encoding technique
The encoding technique for each track shall be Modified Frequency Modulation (MFM) recording for
which the conditions are:
— a flux transition shall be written at the centre of each bit cell containing a ONE,
— a flux transition shall be written at each cell boundary between adjacent bit cells containing ZEROS.
See Figure 8.
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ISO/IEC 7811-7:2014(E)

t t t t t t t t t t t
00 00 00000 0
11 11 11111 1
00 10 10101 1
Key
t indicates bit cell boundaries
Figure 8 — Examples of MFM encoding
The data shall be recorded as a synchronous sequence of characters without intervening gaps.
NOTE 1 Recording with a write current which is less than Imin may result in poor quality encoding.
NOTE 2 MFM is the same as the FM technique described in ISO/IEC 7811-6 except that clocking flux transitions
for 1 bits have been removed. This results in a loss of some of the self-clocking feature with FM encoding and
requires more accuracy for flux transition intervals. With this technique there may not be a flux transition at the
bit cell boundary.
9 Encoding specification
9.1 Angle of recording
The angle of recording shall be normal to the nearest edge of the card parallel to the magnetic stripe
with a tolerance of ± 20 minutes. The angle of recording (α) is determined by measuring the angle of the
head gap when the reading amplitude is maximum (see Figure 9).
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ISO/IEC 7811-7:2014(E)

Figure 9 — Angle of recording
9.2 Nominal bit density
The nominal bit density for each of the tracks shall be 40 bits/mm (1016 bpi).
9.3 Flux transition spacing vari
...