(12) INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT)
`
`(19) World Intellectual Property Organization
`International Bureau
`
`11111111111111 II 11111111111 IIIII II 111111111111111111111111111111111111111 II II 11111111
`
`(43) International Publication Date
`18 July 2002 (18.07.2002)
`
`PCT
`
`(10) International Publication Number
`WO 02/056536 AI
`
`(51) International Patent Classification7:
`
`H04L 9/06
`
`(21) International Application Number: PCT/NLOl/00008
`
`(22) International Filing Date: 9 January 2001 (09.01.2001)
`
`(25) Filing Language:
`
`(26) Publication Language:
`
`English
`
`English
`
`(71) Applicant (for all designated States rncept US): TELE(cid:173)
`FONAKTIEBOLAGET LM ERICSSON [SE/SE]; Tele(cid:173)
`fonvagen 30, S-126 25 Stockholm (Sil).
`
`(81) Designated States (national): AE, AG, AL, AM, A'C AU,
`AZ, BA, BB, BG, BR, BY, BZ, CA, CH, CN, CR, CU, CZ,
`DE, DK, DM, DZ, EE, ES, PI, GB, GD, GE, Gil, GM, HR,
`HU, ID, IL, IN, IS, JP, KE, KG, KP, KR, KZ, LC, LK, LR,
`LS, L:T, LU, LV, MA, MD, MG, MK, MN, MW, MX, MZ,
`NO, NZ, PL, PT, RO, RU, SD, SE, SG, SI, SK, SL, TJ, TM,
`TR, 'IT, TZ, UA, UG, US, UZ, VN, YU, ZA, ZW.
`
`(84) Designated States (regional): ARIPO patent (GH, GM,
`KE, LS, MW, MZ, SD, SL, SZ, TZ, UG, ZW), Eurasian
`patent (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), European
`patent (AT, BE, CH, CY, DE, DK, ES, FI, PR, GB, GR, IE,
`IT, LU, MC, NL, PT, SE, TR), OAPI patent (BF, BJ, CF~
`CG, Cl, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG).
`
`(72) Inventor; and
`(75) Inventor/Applicant (for US only): WEINANS, Erwin Published:
`[NLINL]; Vechtvoorde 96, NL-7772 VC Harden berg (NL).
`with international search report
`
`(74) Agent: VANDER AREND, A., G., A.; Exter Polak &
`Charlouis B.V., P.O. Box 3241, NL-2280 GE Rijswijk
`(NL).
`
`For two-letter codes and other abbreviations, refer to the "Guid(cid:173)
`ance Notes on Codes and Abbreviations" appearing at the begin(cid:173)
`ning of each regular issue of the PCT Gazette.
`
`--
`iiiiiiii ---iiiiiiii
`iiiiiiiiiiiii -iiiiiiiiiiiii
`
`iiiiiiii
`
`--- --------------------------------------------------------------------------------------
`
`(54) Title: METHOD AND SYSTEM FOR BONDING TWO BLUETOOTH DEVICES
`
`(57) Abstract: Method and system for bonding a llrst Blue(cid:173)
`tooth device (5, 8) to a second Bluetooth device (1, 15, 22),
`with both devices placed in a bonding mode, by having the llrst
`devcic to generate a random passkey and transmitting it in a
`manner which is descernible by a user (2) of the devices, or by
`sensor means (11, 19) of a reader unit (10, 18), or by sensor
`means (23) of the other device (22). The reader unit (10) may
`convert a received signal carrying a passkey which is undis(cid:173)
`cernible by the user (2) into a presentation which is discernible
`by user (2). Upon discerning the password the user (2) may en(cid:173)
`ter the password in the other device (1) in the usual way. Said
`other Bluetooth device (15, 22) may have sensor means (16, 23)
`for sensing a signal carrying a password transmitted by a reader
`unit (18) or by the Bluetooth device (8).
`
`BNSDOCID: <WO 02056536A1 I >
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`Page 1 of 14
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`Unified Patents Exhibit 1013
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`wo 02/056536
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`1
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`PCT /NLO 1/00008
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`Title: Method for bonding two Bluetooth devices and system suitable
`for applying the method.
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`The invention relates to a method for bonding two Bluetooth
`devices as described in the preamble of claim 1. The invention also
`relates to a system which is suitable for applying the method as
`described in the preamble of claim 6.
`The Bluetooth technology provides for a short range connection
`between devices based on 2.4 GHz radio technology. The range is
`about 10 meters and the devices do not have to be in line of sight
`to communicate. The maximum bandwidth for data traffic is 1 Mb per
`second. Bluetooth is operating in the free ISM band, which is also
`used by many other devices. Bluetooth prevents disturbance by other
`devices by hopping over 79 frequencies every 1/1600 second.
`When a communication cable between two devices is replaced by
`the use of radio signals for communication there will be a need to
`prevent eavesdropping and falsifying transmitted messages. Therefore
`the Bluetooth technology has built-in functionality for
`authentication and encryption. Authentication is used to prevent
`unwanted access to data and to prevent falsifying of message
`originator. Encryption is used to prevent eavesdropping. These two
`techniques combined with the frequency hopping technique and the
`limited transmission range for a Bluetooth unit give the technology
`higher protection against eavesdropping. Dependent on the
`application which is to be executed the Bluetooth concept provides
`three levels of security:
`1.
`non-secure; this mode bypasses functionality for
`authentication and encryption.
`2.
`service-level security; security procedures on this level
`have not been fully established yet.
`3.
`link-level security; secuLlty procedureB are initiated
`before the link set-up upon completion of a Link Manager Protocol
`(LMP) which is responsible for link set-up between Bluetooth
`devices.
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`The link-level security mode is based on the concept of link
`keys. These keys are secret 128 bit random numbers stored
`individually for each pair of devices in a Bluetooth connection.
`Each time two Bluetooth devices communicate the link key is used for
`authentication and encryption. Both devices contain the same link
`key which is generated locally in each device based on a passkey .
`which is common for both devices or common information derived from
`such passkey. The link key is kept secret in each device.
`If one wants to use two Bluetooth devices with secure
`communication between the devices it is necessary to firstly create
`a trusted relationship between the devices by the user. To that end
`the user puts the devices in a bonding mode upon which the devices
`ask the user to enter a passkey, which may be selected arbi tra·rily
`by the user. Upon entering the passkey in a device the device will
`generate a piece of information based on the passkey. The piece of
`information will be identical for both devices. From then on the two
`devices are bonded and there is no need to keep the passkey by the
`user or the devices any longer. In a second stage the passkey based
`piece of information is used by each device to generate and store a
`common link key. From that moment on the two devices are paired. The
`next time the devices get connected the stored link key on both
`sides will be checked. If the link keys match no request for
`entering a passkey will be generated. If the link keys do not match
`the above bonding and pairing procedures must be carried out again.
`If the Bluetooth devices which are to be bonded are both
`equipped with display means and manual input means, in particular a
`keyboard, there will be no difficulty to enter the passkey by a user
`of the devices for the bonding procedure.
`If one device is not equipped with such an input device the
`device presently needs to contain a factory programmed passkey.
`There are two common ways of handling stored passkeys. Firstly the
`passkeys may be default identical for all manufactured devices of a
`specific type. Secondly the passkeys may be unique per device.
`A drawback of the first solution of handling a factory
`programmed passkey is that the Bluetooth security is weakened. Since
`the value of the passkey is essential for creating the link key and
`the passkey being identical for all devices of the same type a
`Bluetooth connection between them cannot be considered secure.
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`PCT /NLO 1/00008
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`A drawback of the second solution is that the manuf·acturer
`must maintain a logistic system for handling the many different
`passkeys, each unique passkey must be communicated to its ultimate
`user individually, e.g. printed on a box containing a specific
`5 Bluetooth device in which the passkey is stored, and the
`manufacturer must provide a way to restore devices for which the
`passkey is lost. There must be a support organisation for handling
`lost passkey requests. Such a logistic and supporting system will be
`very complex and expensive to maintain.
`It is an object of the invention to solve the above mentioned
`drawbacks.
`Therefore the invention provides a method as described in
`claim 1.
`With the method according to claim 1, for entering a passkey
`in a Bluetooth device, the device needs not to be equipped with a
`keyboard or such type of physical interface, but any other non-radio
`communication interface can be used. In particular such non-radio
`communication. interface is part of the device in the first place for
`normal use of the device. The device may present the randomly
`generated passkey in several ways, such as by transmission of sound
`or light.
`When applying the method according to the invention the
`manufacturer may make all Bluetooth devices generic. Still, the
`devices are able to support Bluetooth encryption in a secure way.
`There are no logistical costs attached to the method. Since the
`passkey is uniquely generated every time the device needs to be
`bonded with another device and on demand by a user of the devices,
`loosing a passkey is not longer an issue and therefore does not
`impose costs for retrieving same.
`The above mentioned drawbacks are solved also by a system as
`described in claim 6.
`The invention will be described in further detail with
`reference to the accompanied drawings .in which:
`fig. 1 shows schematically a system in which a prior art
`35 method is applied for entering a passkey into two Bluetooth devices
`by a user thereof;
`figs. 2, 3, 4 and 5 show first to fourth examples respectively
`of a system according to the invention in which the method according
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`PCT /NLO 1/00008
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`to the invention for entering a passkey into two Bluetooth devices
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`is applied.
`The prior art method shown schematically in fig. 1 is suitably
`for manually entering a passkey into two Bluetooth devices 1 by a
`user 2. The devices 1 may comprise a display means 3 and an input
`means 4, such as a keypad.
`The arrows shown in fig. 1-5 indicate the entering or
`transmission of a passkey.
`Although indicated as Bluetooth devices, the devices 1 and
`those to mention may in fact be larger or complexer pieces of
`equipment containing a pure Bluetooth device integrated therewith.
`For simplicity the devices as a whole are called Bluetooth device.
`The user 2 may choose any suitable passkey arbitrarily. Upon
`putting the devices 1 in a bonding mode the user 2 may enter the
`passkey into both devices 1 by using their input means 4. Upon
`completion thereof each device 1 will use the passkey to generate a
`link key which will be identical for both devices 1. With every
`communication session between the devices 1 the devices 1 will check
`the identity of their link keys by transmitting data which is
`encrypted by the link key and by analysing a similar received
`transmission for its validity or identity with the locally stored
`link key.
`The method exemplified by fig. 2 may be applied for providing
`a common passkey to two Bluetooth devices, such as devices 1, 5, of
`25 which one device 5 does not comprise the input means 4 and possibly
`not the display means 3 of the device 1. Instead, device 5 is
`provided with some kind of transmission means 6. The transmission
`means 6 may be an acoustic or optical transducer for transmitting a
`sound signal or light signal respectively which is discernible by
`the user 2. The light signal may be of any type, such as light
`flashes or the display of readable characters.
`Bluetooth device 5 contains a random number generator (not
`shown) for generating a random passkey upon putting the device 5 in
`bonding mode by user 2. Device 5 will transmit the randomly
`generated passkey, such that the user 2 can hear, read or otherwise
`discern the passkey. Then, user 2 may enter the passkey discerned
`from device 5 into the other device 1 in the same way as with the
`prior art method shown in fig. 1.
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`PCT/NLOl/00008
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`Preferably the transmission means 6 of device 5 consist of
`means which are incorporated in device 5 anyway for normal use of
`device 5, that is apart from said bonding.
`The method exemplified by fig. 3 differs from the method shown
`by fig. 2 in that Bluetooth device 5 is replaced by Bluetooth device
`8 having transmission means 9, and comprising in addition a reader
`unit 10. Reader unit 10 comprises a sensor 11 which is suitable for
`sensing a signal transmitted by the transmission means 9 of device
`8. In addition reader unit 10 comprises transmission means 12 which
`are suitable for transmitting a signal which is discernible by the
`user 2, such as a signal transmitted by
`transmission mea'ns 6 of
`device 5 of fig. 2.
`The
`transmission means 9 of device 8 of fig. 3 may be of a
`type which transmits a signal which is undiscernible by user 2.
`15 Reader unit 10 may be used to convert a signal transmitted by
`transmission means 9 into a transmission signal which is.discernible
`by user 2. Yet, the example of fig. 3 is also applicable for a case
`in which a signal transmitted by
`transmission means 9 is
`discernible by user 2, but which is possibly difficult to discern.
`For example, the signal transmitted by
`transmission means 9 may
`consist of a series of light flashes with short intervals, while
`transmission means 12 may provide a converted presentation of a
`passkey carried by the light flashes, such as a spoken or readable
`message.
`The method exemplified by fig. 4 differs from the method sho~n
`by fig. 3 in that Bluetooth device 1 is replaced by a Bluetooth
`device 15, which comprises a sensor means 16 instead of the input_
`means 4 of device 1, and reader unit 10 is replaced by a reader unit
`18 having sensor means 19 and transmission means 20.
`Reader unit 18 differs from reader unit 10 of fig. 3 basically
`in that a signal carrying a passkey transmitted by transmission
`means 20 need not to be discernible by user 2 but must be suitable
`to be sensed by sensor means 16 of device 15.
`Preferably, sensor means 16 consist of means which are already
`present for normal operation of device 15.
`The method exemplified by fig. 5 differs from the method shown
`by fig. 4 in that Bluetooth device 15 is replaced by Bluetooth
`device 22 having sensor means 23 which are suitable for sensing a
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`PCT /N LOl/00008
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`signal carrying a passkey transmitted by transmission means 9 of
`device 8 directly. The user 2 only needs to bring devices 8 and 22
`in proper proximity of each other.
`As described herein before the method and system according to
`the invention and as exemplified with reference to figs. 2-5 make it
`possible for a manufacturer to only manufacture identical Bluetooth
`devices not containing passkeys and not having passkeys allocated
`thereto, while preserving the possibility of secure communications
`between two Bluetooth devices offered by Bluetooth technology,
`against very reduced costs.
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`PCT/NLOl/00008
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`7
`
`C L A I M S
`
`1. Method for bonding a first Bluetooth device (5, 8) to a second
`Bluetooth device (1, 15, 22) comprising:
`a) placing the devices in a bonding mode;
`
`5
`
`b) providing a passkey which is identical for both devices;
`c) storing the passkey in each device;
`d) generating identical passkey based information in both
`devices;
`e) leaving the bonding mode while further ignoring the
`
`password;
`characterized in that:
`the step of providing a passkey includes:
`b1) generating a random passkey by the first device;
`b2) presenting the random passkey by the first device to its
`outside by non-radio transmission;
`b3) sensing the random passkey from the outside of the first
`device;
`b4) providing the sensed passkey to the second device.
`
`2. Method for bonding two Bluetooth devices (1, 5) according to
`claim 1, characterized in that the sensing of the passkey and
`providing the sensed passkey to the second device (1) are carried
`out by a user (2) of the devices (1, 5) only.
`
`3. Method for bonding two Bluetooth devices (1, 8) according to
`claim 1, characterized in that the sensing of the passkey is carried
`out by a reader unit (10) which is separate from the first device
`(8), the reader unit presents the sensed passkey to its outside by
`non-radio transmission and discernable to a user of the devices, and
`the passkey discerned from the reader unit by the user (2) is
`entered by the user into the second device {1).
`
`4. Method for bonding two Bluetooth devices (8, 15) according to
`claim 1, characterized in that the sensing of the passkey is carried
`out by a reader unit (18) which is separate from the first device
`(8) and the reader unit presents the sensed passkey to its outside
`by non-radio transmission and discernable to a sensor (16) of the
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`PCT/NL01/00008
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`second device (15) to thereby provide the second device with the
`
`passkey.
`
`5
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`5. Method for bonding two Bluetooth devices (8, 22) according to
`claim 1, characterized in that the sensing of the passkey is carried
`out by a sensor (23) of the second device (22) to provide the second
`device with the passkey.
`
`System of a first Bluetooth device (5, 8) and a second
`6.
`10 Bluetooth device (1, 15, 22), the devices comprising:
`a) mode selection means for placing the devices in a bonding
`
`mode;
`
`b) means for providing a passkey to the devices, the passkey
`being identical for both devices;
`c) storage means for storing the respective passkey in each
`device;
`-
`d) generator means for generating identical passkey based
`information;
`e) reset means for leaving the bonding mode and for clearing
`the passkey;
`characterized in that:
`the means for providing the passkey includes:
`b1) generator means of the first device for generating a random
`
`passkey;
`b2) output means (6, 9) of the first device for outputting the
`random passkey by non-radio transmission.
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`System according to claim 8, characterized in that the output
`7.
`means (6} of the first device (5} outputs the passkey in a manner
`30 which makes it discernible by a user (2) of the devices (1, 5) .
`
`SyRtem according to claim 8, characterized by a reader unit
`8.
`(10) having sensor means (11) for sensing the passkey outputted by
`the output means (9) of the first device (8) and having output means
`(12) for outputting the sensed passkey by non-radio transmission and
`discernable to a user (2) of the devices (1, 8).
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`System according to claim 8, characterized by a reader unit
`9.
`(18) having sensor means (19) for sensing the passkey outputted by
`the output means (9) of the first device (8) and having output means
`(20) for outputting the sensed passkey by non-radio transmission and
`discernable to sensor means
`(16) of the second device (15) to
`thereby provide the second device with the passkey.
`
`5
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`System according to claim 8, characterized in that the output
`10.
`means {9) of the first device (8) outputs the passkey in a manner
`10 which makes it discernable to sensor means (23) of the second device
`{22) to thereby provide the second device with the passkey.
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`Fig 1
`
`(PRIOR ART)
`
`Fig 2 ·
`
`9
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`15
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`Fig 3
`
`16
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`Fig 4
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`9
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`Fig 5
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`23
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`

`
`INTERNATIONAL SEARCH REPORT
`
`Inter
`Application No
`PCT/NL 01/00008
`
`A. CLASSIFICATION OfcUSJECT MATTER
`IPC 7 H04L9 06
`
`According to International Patent Classification (IPC) or to both national classification and IPC
`
`B. FIELDS SEARCHED
`Minimum documentation searched (classification system followed by classification symbols)
`IPC 7 H04L
`
`Documentation searched other than minimum documentation to the extent that such documents are Included In the fields searched
`
`Electronic data base consulted during the international search (name of data base and, where practical, search terms used)
`
`EPO-Internal, WPI Data, PAJ
`
`C. DOCUMENTS CONSIDERED TO BE RELEVANT
`
`Category o Citation of document, with Indication, where appropriate, of the relevant passages
`
`Relevant to claim No.
`
`X
`
`A
`
`A
`
`EP 1 024 626 A (IBM)
`2 August 2000 (2000-08-02)
`column 6, 1 i ne 15 -column 7, line 40;
`figure 1
`column 10, 1 i ne 25 - 1 ine 50
`column 13, 1 i ne 5 - 1 i ne 35
`---
`DE 199 24 232 A (GIESECKE & DEVRIENT GMBH)
`7 December 2000 (2000-12-07)
`abstract; figure 1 ---
`wo 97 36422 A (BATCHELOR STEVE ;INTEL CORP
`(US); PERRY BURT (US))
`2 October 1997 (1997-10-02)
`figure 1
`page 2·
`'
`---
`
`-1--
`
`1-10
`
`2,3,7,8
`
`4,9
`
`[]] Further documents are listed In the continuation of box C.
`
`[] Patent family members are listed in annex.
`
`o Special categories of cited documents:
`
`• A' document defining the general state of the art which is not
`considered to be of particular relevance
`'E' earlier document but published on or after the international
`filing dale
`'L' document which may throw doubts on priority clalm(s) or
`which Is cited to establish the publication date of another
`citation or other special reason (as specified)
`'0' document referring to an oral disclosure, use, exhibnlon or
`other means
`•p• document published prior to the international filing date but
`later than the priority date claimed
`
`'T' later document published after the International filing date
`or priority dale and not in conflict with the application but
`cited to understand the principle or theory underlying the
`invention
`'X' document of particular relevance; the claimed invention
`cannot be considered novel or cannot be considered to
`Involve an Inventive step when the document is taken alone
`•y• document of particular relevance; the claimed Invention
`cannot be considered to involve an Inventive step when the
`document is combined with one or more other such docu-
`menls, such combination being obvious to a person skilled
`in the art.
`'&' document member of the same patent family
`
`Date of the actual completion of the international search
`
`Date of mailing of the International search report
`
`28 August 2001
`
`Name and mailing address of the lSA
`European Patent Office, P.B. 5818 Patentlaan 2
`NL- 2280 HV Rijswijk
`Tel. (+31-70) 340-2040, Tx. 31 651 epo nl,
`Fax: (+31-70) 340-3016
`
`Form PCT/ISA/210 (second sheet) (July 1992)
`
`BNSDOCID: <WO 02056536A1 I >
`
`10/09/2001
`
`. Authorized officer
`
`Carnerero Alvaro, F
`
`page 1 of 2
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`Page 12 of 14
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`

`
`INTERNATIONAL SEARCH REPORT
`
`lnterr
`Application No
`PCT/NL 01/00008
`
`C.(Contlnuation) DOCUMENTS CONSIDERED TO BE RELEVANT
`
`Category o Citation of document, with lndlcatlon,where appropriate, of the relevant passages
`
`Relevant to claim No.
`
`1-10
`
`T
`
`"Generic Access
`
`THE BLUETOOTH FORUM:
`Profile"
`BLUETOOTH SPECIFICATION VERSION 1.1,
`'Online! 22 February 2001 (2001-02-22),
`XP002175814
`Retrieved from the Internet:
`<URL:http://www.bluetooth.com/developer/sp
`ecification/BLUETOOTH_l1_Profiles_Book.pdf
`> 'retrieved on 2001-08-24!
`cited in the application
`page 29
`page 43 -page 45
`page 53
`
`-----
`
`Fonn PCT/ISN21 o (continuation of second sheet) (July 1992)
`
`BNSDOCID: <WO 02056536A 1 I >
`
`page 2 of 2
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`Page 13 of 14
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`

`
`INTERNATIONAL SEARCH REPORT
`
`Intern;
`I Application No
`PCT/NL 01/00008
`
`I Publication
`
`date
`
`09-08-2000
`11-08-2000
`
`18-12-2000
`07-12-2000
`
`27-02-2001
`17-10-1997
`02-10-1997
`13-01-1999
`
`Patent document
`cited in search report
`
`EP 1024626
`
`A
`
`I
`
`Publication
`date
`
`02-08-2000
`
`I
`
`DE 19924232 A
`
`07-12-2000
`
`wo 9736422
`
`A
`
`02-10-1997
`
`Patent family
`member(s)
`
`1262563 A
`CN
`JP 2000224156 A
`
`AU
`wo
`us
`AU
`CA
`EP
`
`5809800 A
`0074003 A
`
`6195501 B
`2321097 A
`2250925 A
`0890260 A
`
`Fonn PCTilSN210 (patent famlly annex) (July 1992)
`
`BNSDOCID: <WO 02056536A1 I >
`
`Page 14 of 14