Title of Invention

"METHOD FOR SECURING AN ELECTRONIC CERTIFICATE"

Abstract Method for securing and verifying an electronic certificate (C) issued by an authority (AU) to an owner, said certificate (C) being stored in a memory of each user unit (PC) of a plurality of user units operated by the owner, each user unit (PC) being able to transmit all or part of the data of the certificate (C) to a server of the authority (AU), wherein, during an initialization phase, said method comprising: - determining by the authority (AU) for each user unit a network identifier (HID) based on hardware configuration parameters received from this user unit (PC), - storing the network identifiers (HID) in a database (BD) of the server of the authority (AU) by linking said network identifiers (HID) with the data of the certificate (C), said data of the certificate (C) having a plurality of links, each link pointing towards a distinct network identifier (HID) identifying in a unique way one of the user units (PC), - verifying during access to a service from a service supplier by the user unit (PC), - identifying the owner by the transmission of the certificate (C) to the service supplier (SP), - determining, by the service supplier (SP), a network identifier (HID) based on hardware configuration parameters of the user unit (PC), -transmitting the set formed by the certificate (C) and the network identifier (HID) to the authority (AU), -verifying said set by comparison with the data registered in the database (BD) during the initialization step, - transmitting the result of the comparison to the service supplier (SP) that authorizes the previously requested service to the connected user according to said result. Fig.l
Full Text The present invention relates to a method for securing and electronic certificate.
METHOD FOR SECURING AN ELECTRONIC CERTIFICATE
Introduction
The present invention concerns a method for securing an electronic certificate, in particular to avoid its copying and its use by a third party
An electronic certificate is a digital file that can be compared to a virtual passport.
Background art
Like a passport, it contains a certain number of personal data corresponding to its owner It is issued by a recognized authority that can guarantee the authenticity of the data contained in the certificate and its inseparable link with the owner.
This certificate is stored in the memory of a user unit such as the hard disk of a computer, the memory or the SIM card of a mobile phone, the security module of a digital pay television decoder or all other devices requiring on-line identification of the user The latter can thus securely communicate through a telecommunication network by adding the certificate with the transmitted data.
The certificate allows, for example, identification on the Internet, the generation of electronic signatures for transactions of high added values and to transmit sensitive data with complete confidentiality,
Today, it is possible for a third party to copy a certificate without the authorization of its owner with the help of an adequate program such as Trojan horse The third party can thus fraudulently take advantage of the same privileges as the owner when using on-line services When financial transactions or particular rights concerning the diffused products are concerned, the consequences of this type of fraud can be particularly disastrous for the owner
The document US2003/0084I72 describes a method for obtaining a service on a data communication network comprising a registration from an authority. The results of this registration are used to obtain a service from a supplier These results contain data pertaining to the user that the supplier is capable of verifying by requesting data from the authority. The drawback of this method is that it uses data linked to a user, data that can be picked up and reproduced by another user with the aim of obtaining services in a fraudulent way.
Brief description of the invention
The aim of this invention is to prevent the use of the certificate by any individual other than the owner and to avoid all damages to the owner in the case of theft or copying of the certificate.
This aim is achieved by a method for securing an electronic certificate issued by an authority to an owner, said certificate being stored in the memory of a user unit operated by the owner, said user unit transmits all or part of the data of the certificate to the authority, characterized in that, during an initialization phase, said method comprises the following steps:
determination by the authority of a network identifier based on hardware configuration parameters of the user unit,
storage by the authority of said identifier in connection with the data of the certificate.
These steps essentially concern the initialization step. During normal operation, a verification step is activated when the owner of the certificate operates its unit by using his certificate together with a predetermined service originating from a service supplier. It includes the following steps:
identification of the owner by the transmission of the certificate to the service supplier,
determination by the service supplier of a network identifier based on hardware configuration parameters of the user unit,
transmission of the set formed by the certificate and the network identifier to the authority,
verification of said set by comparing with the data registered in the database during the initialization step,
transmission of the result of the comparison to the service supplier who authorizes the previously requested service to the connected user according to said result.

The network identifier pertaining to the user unit consists of data serving to identify in a unique way the unit within a telecommunications network. This network serves to access successively the authority and the service supplier, this identifier not being transmitted as such by the user unit but rather being determined in an autonomous way by either the authority, or the supplier on the basis of physical parameters of the communication. According to the method of the invention, it is achieved a matching of the certificate with the physical parameters of the user unit or more precisely with the unit that uses on-line services in order to avoid the fraudulent copying of the certificate of the memory of a unit towards the memory of another.
In the case of the Internet connection, each computer transmits a number defining it in a unique way on the network. This number, called MAC (Media Access Control) address identifies the configuration of the material of a user and is automatically determined by the server of the service supplier. The certificate of a user unit connected to this server can be "personalized" in this way with the aid of this address. This address is thus not communicated as a parameter by the user unit but is the results of its capacity to transmit on a network. This address cannot be modified (at least easily) by the owner of the certificate or by a third party who has copied this certificate.
Within the scope of GSM mobile telephony, the unique number identifying each mobile telephone, called IMEI (International Mobile Equipment Identity), connected to the network can be used as an identifier of the unit being used.
In a similar way, a Pay-TV decoder disposing of a return channel can be identified by an operator by means of its unique number that characterizes its hardware or by means of the telephone number used by the modem of the return channel.
In general, all apparatus connected to a network have an address or a number specific to its hardware configuration that allows the apparatus to be identified by a server or by other apparatuses with which it communicates.
During the initialization phase, the user unit is directly connected to a server managed by the authority responsible on one hand for receiving data related to the certificate or the certificate in its entirety and on the other hand for determining a

network identifier relating to the user unit. The authority registers in a database this identifier by linking it with the corresponding certificate.
This initialization is preferably carried out once for a given certificate in order to avoid multiple registrations of network identifiers originating from several units for the same certificate.
It is also possible to limit initialization in a time period by fixing a maximum period length during which it is possible to register a certificate with the authority, for example starting from the transmission of the certificate to the user.
This procedure is preferably related to the setting up of the certificate in the user's apparatus. This procedure includes a call to the authority to establish and to add the network identifier of this apparatus to the data of the certificate. It is possible to render this connection obligatory, for example during the dialogue between the authority and the user apparatus, the authority transmits an instruction that validates the certificate and authorizes its use.
According to an embodiment of the method of the invention, a code or password can be used during the connection of the user to the authority's server. This code serves in a way to authorize the link between the network identifier and a certificate with the authority issuing the certificate. Said code is preferably transmitted to the user through a different channel from the one used for the certificate in order to preserve its confidentiality. For example, this password or PIN code can be sent to the user by post, as is the case with banking cards. Following the registration of the network identifier with the certificate, the password can be disabled in order to avoid the multiple registration of the same certificate by different units.
In this embodiment, the validity duration of the code can be fixed in the same way as in the previous embodiment in order to allow registration in a limited time period. In a case where this period was exceeded, it would be necessary to request a new code from the authority for an eventual supplementary cost.
According to another embodiment of the method according to the invention, several units belonging to a common user and each having a different network identifier can be registered in association with the same certificate. This situation could occur

during the use of a certificate on a removable support such as a smart card. The use of the certificate is then limited by the group of units whose identifier is duly registered in database of the authority. This type of registration could be carried out not only with a unique password but also with a list of different password for each unit.
Brief description of the figures
The invention will be better understood thanks to the following detailed description that refers to the annexed figures, illustrating the method according to the invention, given as a non-limitative example.
Figure 1 represents a block schematic illustrating the initialization step of a certificate on a user unit
Figure 2 represents a block schematic illustrating the verification step of a certificate on a user unit
Detailed description
The management center of the authority (AD) comprises a certificate-issuing center (Cl) responsible for producing and managing the certificates and a verification center (VE) linked to a database (BD) containing the certificates (C) accompanied by the data (HID) pertaining to units used by the owners of the certificates (C).
In the case of computers connected to the Internet, the services using the certificates consist for example in a secured connection for electronic trading, a privileged access to programs or to protected data.
During initialization or the acquisition of a certificate by a user, the latter receives a password that is usually in the form of a PIN code (Personal Identification Number) with his new certificate (C). The user can connect with the verification center VE and declare the characteristics of his certificate. This code allows the user to prove that he is the legitimate owner of this certificate and once introduced, the verification center VE reads the network identifier HID of the user and associates this identifier with the certificate C.

This initialization step can be carried out with several devices that can contain the certificate of the user if for example this certificate is on a removable support such as a smart card. All the network identifiers HID will be associated with this certificate thanks to the introduction of the password. In order to simplify the procedure at user level, it is not necessary, neither useful, for the identifier HID to be known to the user. The registration of this parameter with the certificate C is thus carried out automatically after the introduction of a valid PIN code.
The certificate C is thus activated and usable as long as the user conserves said certificate on the device whose identifier HID has been registered. The transfer of this certificate C to another computer remains possible, but said certificate becomes unusable because the MAC address of this second computer is not registered in the database BD of the authority AD. It is to be noted that the certificate is connected to a particular computer that is different from the others, in this example, by its MAC address.
Figure 2 shows the using step of such a certificate. The user accesses a service managed by a service supplier SP. The latter reads the certificate that is transmitted by the user and determines an identifier HID allowing the definition of the user's parameters PC on the network used to access the supplier SP.
In this example, the identifier corresponds to the computer's MAC address of the owner of the certificate C.
The service supplier SP determines the MAC address of the computer PC that is connected then transmits this address to the verification center VE with the certificate C.
The verification center can compare the data transmitted by the supplier SP with the data stored in the database BD. The result of the comparison will be transmitted to the supplier SP that authorizes the use of the service only if the current MAC address of the computer requiring a service corresponds to the address associated with the certificate C in the database BD.
According to an embodiment, a certificate (C) can be registered with several IP addresses belonging to computers managed by the same owner. In this case, the

certificate can be stored in the database of the authority with the links pointing towards the different addresses with which it has been activated.
A certificate, registered with the authority according to the method of the invention, can also be deactivated. In fact, it is desirable to allow an owner to be able to update the database of the authority when he changes his unit or wishes to cancel his certificate. Given that the authority has no direct control over the characteristics of the users' computers, the modifications are carried out in a similar way to the activation of a new certificate during the initialization step.
On request, the owner receives a new PIN code or password serving to reactivate a certificate predefined in a new computer and/or deactivate said certificate. In the case of a reactivation, during the access of the owner to the authority, the latter determines the new MAC address to be transmitted to the database in order to associate this new address with the certificate.
During a configuration modification such as a deactivation, in a first embodiment, the identification of the owner of a certificate is carried out by the determination of the network identifier HID. The owner transmits the certificate to the verification center and the latter determines the network identifier HID. The comparison with the data contained in the database allows the authentication of the user and the authorization to introduce modifications to his profile.
In another embodiment, the introduction of a PIN password is essentially required for each modification.









We Claim:
1. Method for securing and verifying an electronic certificate (C) issued by an
authority (AU) to an owner, said certificate (C) being stored in a memory of each user
unit (PC) of a plurality of user units operated by the owner, each user unit (PC) being
able to transmit all or part of the data of the certificate (C) to a server of the authority
(AU), wherein, during an initialization phase, said method comprising:
determining by the authority (AU) for each user unit a network identifier (HID) based on hardware configuration parameters received from this user unit (PC),
storing the network identifiers (HID) in a database (BD) of the server of the authority (AU) by linking said network identifiers (HID) with the data of the certificate (C), said data of the certificate (C) having a plurality of links, each link pointing towards a distinct network identifier (HID) identifying in a unique way one of the user units (PC),
verifying during access to a service from a service supplier by the user unit (PC),
identifying the owner by the transmission of the certificate (C) to the service supplier (SP),
determining, by the service supplier (SP), a network identifier (HID) based on hardware configuration parameters of the user unit (PC),
transmitting the set formed by the certificate (C) and the network identifier (HID) to the authority (AU),
verifying said set by comparison with the data registered in the database (BD) during the initialization step,
transmitting the result of the comparison to the service supplier (SP) that authorizes the previously requested service to the connected user according to said result.
2. Method as claimed in claim 1, wherein the storage of the network identifier (HID)
in connection with the data of the certificate (C) is subject to the introduction of a
password (PIN) by the owner.
3. Method as claimed in claim 2, wherein the password (PIN) associated with the
certificate is received by the owner of the certificate through a different channel from the
one used for transmitting the data of the certificate (C).
4. Method as claimed in claim 2, wherein the password (PIN) associated with the
certificate (C) is disabled after the linking operation of the data of the certificate (C) with
the network identifier (HID) in the database (BD) of the server of authority (AU).
5. Method as claimed in claim 1, wherein the network identifier (HID) consists of an
address or a number identifying in a unique way the unit on the network to wh|ch it is
connected.



Documents:

28-delnp-2006-abstract (granted).pdf

28-DELNP-2006-Abstract-(07-12-2009).pdf

28-delnp-2006-Abstract-(22-07-2011).pdf

28-delnp-2006-abstract.pdf

28-delnp-2006-claims (granted).pdf

28-DELNP-2006-Claims-(07-12-2009).pdf

28-delnp-2006-Claims-(22-07-2011).pdf

28-delnp-2006-claims.pdf

28-delnp-2006-Correspodence Others-(22-07-2011).pdf

28-DELNP-2006-Correspondence-Others-(04-06-2010).pdf

28-DELNP-2006-Correspondence-Others-(07-12-2009).pdf

28-DELNP-2006-Correspondence-Others.pdf

28-DELNP-2006-Description (Complete)-(07-12-2009).pdf

28-delnp-2006-description (complete).pdf

28-DELNP-2006-Drawings-(07-12-2009).pdf

28-delnp-2006-drawings.pdf

28-DELNP-2006-Form-1-(07-12-2009).pdf

28-delnp-2006-form-1.pdf

28-DELNP-2006-Form-18.pdf

28-delnp-2006-form-2.pdf

28-DELNP-2006-Form-3-(07-12-2009).pdf

28-delnp-2006-form-3.pdf

28-delnp-2006-form-5.pdf

28-DELNP-2006-GPA-(07-12-2009).pdf

28-delnp-2006-gpa.pdf

28-delnp-2006-pct-210.pdf

28-delnp-2006-pct-409.pdf

28-DELNP-2006-Petition-137-(07-12-2009).pdf

28-delnp-2006-petition-138.pdf


Patent Number 248666
Indian Patent Application Number 28/DELNP/2006
PG Journal Number 31/2011
Publication Date 05-Aug-2011
Grant Date 02-Aug-2011
Date of Filing 02-Jan-2006
Name of Patentee NAGRAVISION S.A.
Applicant Address ROUTE DE GENEVE 22, CH-1033 CHESEAUX-SUR-LAUSANNE, SWITZERLAND.
Inventors:
# Inventor's Name Inventor's Address
1 PHILIPPE STRANSKY CHEMIN DES GRANDS-CHAMPS, CH-1033 CHESEAUX-SUR-LAUSANNE, SWITZERLAND.
PCT International Classification Number H04L 9/32
PCT International Application Number PCT/IB2004/051129
PCT International Filing date 2004-07-06
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 01232/03 2003-07-14 Switzerland