System for and method of verifying a document

The invention relates to a method of carrying an information object. A typical information object is an electronic document transferred to authorized recipients.

Paper documents are traditional evidence of meetings and agreements between the parties in commercial or other transactions. Financial and real estate transactions are protected by paper-based collateral. Signatures or secure documents (such as pre-printed checks) make it easier to detect any unauthorized change of information regarding a commercial transaction. Important documents can also be secured with a "third person" by certifying the signatures by both a seal and a notary.

However, the ways of doing business have changed dramatically and are constantly evolving. A clear example of this is the replacement of traditional paper means of communication with electronic means. Security features for paper-based communications do not exist in electronic transaction procedures. Standard electronic communication using open systems does not have the same ability to ensure the authenticity, privacy and integrity of the information transmitted. By "authenticity" is meant the verification of the identity of the signatory of the document; "privacy" should be understood as securing the information contained in a document against unauthorized access; and by "integrity" is meant the ability to detect any change in the content of the document.

Signatures or seals verifying the sender's identity do not exist when communication takes place with the use of electronically reproduced documents such as e-mail, facsimile devices, imitation, electronic data exchange or electronic capital transfer. Traditional legally accepted means of verifying the identity of the document issuer, such as physical presence or occurrence, ink signature, personal endorsement or notary certification, are not applicable.

The continuous development of computer and telecommunications technology is unfortunately accompanied by the inventing of more and more sophisticated ways of intercepting and changing information transmitted electronically, including the widespread phenomenon of remote hacking into computer systems through telecommunications links. It is especially easy to intercept messages transmitted over the air. A method and device for providing privacy and authenticity in wireless networks is disclosed in US 5,371,794. Messages transmitted between the fixed base and mobile stations of the wireless network are in this solution verified with the public and private keys of the base and the mobile stations.

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Some of the ways of introducing secure electronic transaction technology by means of cryptography provide the user with a verification mechanism to authorize or secure the document against unauthorized access that is controlled by the user and does not include an anti-forgery component. In some cases, the use of encoding for information protection purposes can help detect document changes to ensure document integrity. This is not a general case, however, an additional mechanism may be introduced to ensure integrity.

Currently, there is no widespread electronic document verification system that can introduce verification such as written or printed documents in a way that cannot be forged. None of the commercial systems introduce signature-based electronic document verification that could not be forged, although some such attempts will be described. See, for example, D. Chaum, "Achiving Electronic Privacy," Scientific American, vol. 247, no 8, pages 96-101 (Aug 1992); CR Merrill, "Cryptography for Commerce beyond Clipper", The Data Law Report, vol 2, no 2, pages 4-11 (September 1992).

A system of additional verification that prolongs the credibility of a digitally signed message despite possible misappropriation of the private key or advances in computer technology has been disclosed in U.S. Patent No. 5,373,561. Corresponding time and date stamps entered into the system are described in U.S. Patent Applications No. 5,136,646. and No. 5,136,647 by Stuart A. Habef and WS Stometta, Jr., and further commercially available.

Well-known certificates and certification networks are described in cited publications by C. RMerrill and in ITU-T Recommendation Χ.509 (1993) IISO / IEC 9594-8: 1995 Information Technology Open Systems Interconnection The Directory: Authentication Framework (including all with amendments), which are are incorporated herein by reference. The infrastructure and certificate definitions used in these applications are based on these documents.

Apart from DES, no government organization or other standardization body has been able to introduce a standard (regarding cryptographic robustness of processes, and the like) that could be released for general use. The techniques described in this application are synergistic and introduce sufficient security to meet the security requirements of a typical transaction.

Various aspects of Public Key Cryptography (PKC) coding systems are described in the literature, including works by R. L Riversf and others, "Method for Obtaining Digital Signatures and Public-Key Cryptosystems", Communications of ACM vol 21, pages 120-126 (February 1978); ME Hellman, "Mathematics of Public-Key Cryptography," Scientific American, Vol. 234, No. 8, pp. 146-152, 154-157 (August 1979); and in. Diffie, "The First Ten Years of Public-Key Cryptography," Proceedings of the IEEE, vol 76, pages 560-577 (May 1988). Popular PKC systems take advantage of the fact that finding great primes is computationally easy, but the factorization of the result of multiplication of two great primes is computationally complex. The PKC system is an asymmetric coding system. This means that it uses two keys, one for encoding and one for decoding. Asymmetric systems follow the assumption that the knowledge of one key (public key) does not allow the calculation of the second key (private key). Thus, PKC allows the user of the private key to be sent publicly (for example, in a directory or public service) without fear of finding the user's private key on this basis.

A pair of appropriate public and secret private keys are used in the digital signature algorithm disclosed in U.S. Patent No. 5,231,668. The issuer of the document generates, using said key pair, a second pair of numbers which, upon processing with a known hash function, appends to the transmitted message. The recipient checks that the sent numbers are in the correct relationship.

Besides the PKC method, another encoding method is a symmetric algorithm. An example of which is the Data Encryption Standard DES (Data Encryption Standard) which it describes

182 163 is in the Data Encryption Standard, Federal Information Processing Standards publication 46 (1977) ("FIPS PUB 46", re-published as FIPS PUB 46-1 (1988)) and DES Modes of Operation, FIPS PUB 81 (1980), which are available from the US Department of Economics. See also W. Dieffie et al., "Privacy and Authentication: An Introduction to Cryptography," Proc IEEE vol. 67, pages 397-427 (March 1979). Generally, a symmetric coding system is a set of instructions, implemented either in hardware, software, or both, that can transform plain text (unencoded information) into cryptotext or vice versa in many ways using specific keys that are known to users but are kept secret from others.

In both symmetric and PKC systems, message security is highly dependent on key length, as described in CE Shannon's "Communication Theory of Secrecy Systems", Bell Sys. Tech. J. vol. 28 pages 665-715 (October 1949).

The method of carrying the information object, in which the information object encodes and secures with a digital signature, according to the invention is distinguished by that the information object is signed with a first digital signature of the first entity, a first certificate is attached to the information object by the first entity, the first certificate being associated with a cryptographic key. with the identity of the first individual, the signed information object with attached first certificate is sent and the transmitted, signed information object with attached first certificate is verified.

Preferably, the information object is digitally encoded, the identity of the first entity is certified, a public key and a private key are generated, and at least one of the private or public keys is used to digitally encode the information object while maintaining the integrity and acceptability of the transmitted information object.

During certification, preferably a personal identification number and at least one of the private and public keys are provided to the creator of the information object.

During verification, the integrity block and the date and time stamp are preferably incorporated into the transmitted, encoded and signed information object.

Preferably, when verifying, a date stamp and a time stamp are included in the information object, the first digital signature and the first certificate of the first entity are checked, the information object is signed with a second digital signature, and the second certificate is attached to the information object signed with the second digital signature after the first digital signature has been checked. , where the second certificate binds the cryptographic key to the second digital signature and is archived, in the team identified by the second digital signature, the information object signed with a second digital signature and having a second certificate attached, and gives control of the document to the team.

For an information object in which a first certificate attached to the information object by a first entity associates at least an identity and a cryptographic key with a first entity, and the verification of the information object signed with the first digital signature with the attached first certificate is performed with the second entity, and a verified object is created, the first digital signature and the first certificate are good at the verification stage, a date stamp and a time stamp are appended to the information object signed with the first digital signature and having the first certificate, and after checking and appending the tags, the checked information object with the tags is checked by signing the information object with a second digital signature of the second entity, a second certificate is attached to the information object and the verified, tagged information object signed with a second digital signature is archived and has a second certificate attached as a verified object, while the second certificate binds at least the identity and cryptographic key of the second entity, and the verified object is sent to the entity according to the instructions , whereby the transaction is made by transmitting a verified information object with verifiable evidence history.

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During transmission, the stored verified object is preferably retrieved and the retrieved verified object is made available to the entity. The found verified object is preferably made available to each of a plurality of entities.

When signing, preferably a hash function is applied to the information object to obtain the message set, and the message set with the secret cryptographic key of one of the first and second entities, respectively, is used to determine the corresponding digital signature.

The checking preferably uses a digital signature along with the public cryptographic key of the first entity along with the next set of messages determined by applying a hash function to the information object. Furthermore, a verified object register is preferably maintained to identify at least one further information object associated with the transaction operation.

Preferably, the further information object is signed with a third digital signature of the third entity.

The document verification system DAS (Document Authentication System) according to the invention provides the expected level of security and protection of electronic transactions. Most importantly for financial and economic institutions, the inventive DAS takes risk and responsibility for the authenticity of documents. The DAS document verification system of the invention uses an asymmetric coding system known as the public key system to ensure that the issuing party is electronically identifiable as such.

The solution according to the invention comprises means for identifying the issuer of an electronic document, aimed at ensuring the undisputed document of transmission integrity of the electronic document, and means for eliminating the situation in which the issuer of the document denies being its issuer, i.e. document falsification.

The subject of the invention is explained in more detail on the basis of the drawing, in which fig. 1 shows a block diagram of the allocation of the authentication used for verification in the DAS, fig. 2 - description of the functions of the DAS document verification system related to document transmission, verification and security, fig. 3 - simple diagram of the DAS architecture. 6 - a diagram illustrating the application of DAS in the area of ​​mortgage loans, where the Representatives are the company / agent finalizing the loan, Fig. 7 general course of the document certification process, Fig. 8 - a block diagram of the digital signature production process, Fig. 9 - a block diagram of the document digital signing process and Fig. 10 for the format of a certificate used by the user or certifier, Fig. 11 for checking certificates, and Fig. 12 shows a block diagram of the certificate generation process.

The present invention can be implemented using commercially available technologies and computer systems to form an integrated closed system for the verification of electronic documents.

Referring to Figure 1, which shows the authentication allocation block diagram used in the applicant's DAS, the DAS uses a network of certifying issuers by which the public / private key that is used to encode / decode and / or digitally sign the document is provided to the issuer. document by established and verifiable means.

As described below, the public / private key is preferably transferred in a material form such as an electronic circuit card conforming to the standards of the PC Memory Card Interface Association (PCMCIA card or PC card) for use on the document issuing computer. In general, a physical form can be defined as any portable transportation device that is used to carry keys or parts of keys. It is understood that PC Cards are only one of the public / private key delivery mechanisms in the applicant's DAS; Other kinds of physical forms such as ela disks may be used

182 163 tangents or smart cards. To ensure reliable delivery, services such as courier services commonly used to transport secret correspondence between parties to deliver the medium to the issuer of the document may be used.

Advantageously, there are many carriers available in the market that have a built-in encryption mechanism generating public / private key pairs on the cards, and the private key never leaves the card unencrypted. Public keys are exported to the Inclusion Certification Authority, along with the identity of the specified recipient and applied user attributes among other items for certification. The essential elements of the DAS security system are the correct operations of the certifying issuer network, the close association of the user's identity and attributes with the public key in the certificate, and the reliable delivery of the PC card to the authorized recipient.

In additional aspects of the applicant's invention, a public / private key is effective when used in conjunction with a certificate and personal identifying information such as recipient's biometric information (e.g., eye retinal pattern, fingerprints and voice analysis) or a Personal Identification PIN (Personal Identification Number). Number), which is assigned to the card recipient by the certifying issuer and which can be provided independently by the card issuer. It may be entered, with the appropriate card and personal identifying information, on any other intermediate body carrying the document that is required to electronically sign or encode the document.

In Figure 1, the issuer of the document and each of the following intermediaries I call representatives, it is obvious that the Representative is identified in the DAS document verification system by having and using a validated certificate and validated PIN. In issuing the key and PIN to the Representative, the DAS preferably stores one or more attributes or characteristics of the Representative in association with the key and PIN. For example, a Representative may be authorized to only carry out transactions of a certain type and / or transactions of less than a predetermined value.

The issuance of a digitally signed certificate by the certifying authority ensures the verifiability of the identity of each of the intermediaries of a digitally signed or encrypted document. The certifying issuer retains the ability to withdraw the public / private key or reissue the public / private key electronically. The certifying issuer can also handle the rights management according to the settings for the system. For example, the Certifying Authority may set financial or other types of limits on the permissions granted to an Intermediary by passing those permissions or restrictions as attributes of the certificate. These attributes can be extracted from the certificate and used by other elements in the system.

In an important aspect of the applicant's invention, the DAS is a document verification system by using digital signature encoding technology in the electronic transmission of documents. As used herein, the term "verification" means identifying and verifying the identity of a party that uses, secured, or transmitted original documents, and verifying that the received encoded document is a document posted by that party. DAS uses a certifying issuer to implement screening or evidence proceedings for applications that require such procedures, starting from the original use of the issued or encoded or secured document through all subsequent transmissions.

The certificate issuer may use physical security measures, which are security centers with a 24/7 surveillance system, an alarm system, and a "closed" structure. From the point of view of its security, the security measures may advantageously include two-person supervision, so that a single person does not have access to the key generation or key management system. All personnel related to the cryptographic key management operations and the transmission of electronic documents are checked for plausibility as strictly as possible, e.g. personal interview, background checks

182 163 past, lie detector test, and the like. Moreover, the managing system of the certifying issuer may have procedures implemented that prevent the occurrence of one-way errors, the removal of which requires cooperation. In this way, one person cannot get complete access to the key generation and key management system.

Another aspect of applicant's DAS verification, unlike previously known systems, is the use of an integrity block and date and time "stamps" on each forwarded document. The integrity block, that is, a digital signature, and time and date stamps that are placed by the certifying issuer eliminate the possibility of unauthorized alteration or forgery of the document by signing parties subsequent to the original publisher. The certifying issuer integrity block for the document received from the Representative is generated using several known encoding algorithms. The integrity block ensures that the document cannot be altered unnoticed. Moreover, the use of the digital signing algorithm by the Verification Center can advantageously ensure identity verification, that is, prevent the issuer from disavowing the document. The applicant's combination of an integrity block, time and date stamps, and control ensures that any attempt to change or replace, even by the issuer of the document, is noticed and recorded when such an attempt is made after issue.

According to the applicant's invention, each transaction and each document is verified by sending from the Representative's terminal to the Verification Center. The Representative enters the document in a digital form, such as a conventional word processor file, into his PCMCIA card as described below. Optionally, a handwritten signature digitizing device may be introduced, the handwritten signature in digital form may also be attached to the digital document. The digital document is digitally signed and / or encoded by the DAS PCMCIA card, and the digitally signed and / or encoded version is sent to the Verification Center (for example via modem or computer network). Other means of transmitting a digitally signed and / or encoded document may be used (for example, transmitting a floppy disk containing the document), but the great advantage of electrical communication is speed. The Verification Center verifies the identity of the Representative and the authenticity of the documents, then attaches a digital signature and date and time stamps to the document, so that each transaction is established in a manner that cannot be forged. The combination of these functions, in conjunction with a protected security investigation, may be used in the future to prove that the party initiated the transaction.

In particular, the applicant's invention introduces the verification of documents in a way that prevents the issuer from issuing the document, and introduces an indisputable proof of authenticity. Verified, digitally signed and / or encrypted documents are stored by the third party Verification Center in an appropriate form, such as on optical and / or magnetic disks. When a transaction is closed and the digitally signed document or documents are uploaded and verified by the Verification Center, each of the authorized parties may access the Verification Center through an electronic device such as a modem to receive or forward the verified document. All transmissions of electronic documents from the issuer are made to the Verification Center, which performs verification as described above, and stores the verified documents to be sent to and with the authorization of verified parties whose identities and entitlements are similarly verified by the Verification Center. Verification on the grounds of right of access may be restricted to a single document or group of documents.

According to the applicant's invention, the DAS system verifies and ensures that documents that have been sent, stored or retrieved have not been accidentally or intentionally altered. The DAS can determine at any stage at any time whether the document is accurately

182 163 to the last bit, a document that was issued and sent by the issuer, and that the document has not been altered or damaged in any way. This element of integrity combined with a digital signature and date and time stamps makes the DAS ensure that the document is not fabricated, is not a counterfeit issued by persons pretending to be the issuer or is unauthorizedly replaced by a document that was not originally issued or secured by the issuer. When issuers of documents sign and / or code documents such as loan or mortgage documents, documents of economic importance and other securities, property rights or leasing documents, and the like, it should be possible to carry out their transactions from different locations, DAS it transfers the heart of the cryptographic process to the PCMCIA encoding card belonging to the appropriate authorized representative. This allows individual use of any available DAS computer at any location that is connected to the network or connected to the Verification Center.

As described above, coding cards and certificates are issued and supervised by a certifying issuer. The certificates can also be checked by including the "validity period" field, which ensures periodic replacement, if necessary, of the certificates belonging to the Representatives. Only those fields which are essential for understanding the operation of the invention will be described herein.

Figure 2 outlines the document transmission, verification and security functions of the DAS. The functions of the Representative's PC Card are shown in the left column; the central column shows the functions performed by the Representative's transmission device; and in the right column there are functions of the DAS system. Fig. 3 is a diagram showing the interrelationships between the three Representatives' terminals and the server subsystem and the security subsystem in the Verification Center in the DAS architecture. Fig. 4 is a block diagram of the functional relationship between the Representative and the Verification Center.

The coding card includes components such as a microprocessor and electronic memory devices for carrying out the steps of a PKC algorithm as well as a symmetric coding algorithm such as DES. In addition, the card should be secured against access by third parties, which can be ensured by removing certain critical keys and / or algorithms with any attempted break-in or alteration. The National Institute of Standards and Technology has been asked to certify suppliers of coding cards that will perform the verification and that can be used by the DAS. According to the applicant's invention, each transaction and each its document are verified using the public key contained in the Representative's certificate. Hardware and software with which confidentiality, signature and / or integrity can be ensured are available from many known sources.

The Verification Center uses its own secret key to re-sign transactions in a way that cannot be forged. The combination of signatures of the Representative and the Verification Center (in conjunction with a physically secured screening procedure) may be used in the future to ultimately prove that the agent, employee or company (Representative) initiated a specific transaction. In addition, it is possible to use the notarization function as described below.

An employee or agent registered at the Representative Terminal is secured by the personal identification information and coding functions of the coding card held by the Representative. The combination of these elements uniquely identifies the agent or employee, which makes the DAS possible. In addition, the agent or employee verification information may be stored in a certificate or PCMCIA card memory in a secure form as described above. DAS uses this information in conjunction with the PIN to set the privileges, access rights, sizes and limits of available funds.

The DAS introduces a distributed verification capability using a "signature" that cannot be forged. The strategy uses PKC to reduce the burden of key management and to introduce a digital signature for everyone

182 163 documents and transactions that cannot be falsified. Coding is used to protect the confidentiality of the PIN and other transaction details as described above. The control functions of the DAS are summarized in Fig. 5.

Moreover, the DAS system is compatible with the full range of modern applications, distributed based on client / server transactions. It works effectively in LAN, WAN and Dial up networks. DAS makes good use of modern database tools and thus the server can use relational technology in conjunction with an SQL interface (for example SYBASE). DAS can use many technological tools, the groups of which are listed below. The security architecture can allocate credentials in a way that cannot be spoofed by industry standards. Specifically, ANSI Χ9.9 and X9.19, which are incorporated herein by reference, which may be used for verification. The DES standard can be used to encode documents and the triple encryption can be used to secure the encryption key. The session key management option from ANSI Χ9.24, Finacial Institution Retail Key Managment, which is incorporated herein by reference, can be used in conjunction with the security architecture. In one aspect of the applicant's invention, documents, transactions and other information may be secured using an ANSI cryptographic standard. PINs may be encoded using DES; selected message elements can be verified using the methods specified in ANSI Χ9.9, Financial Institution Message Authentication (in full); The encryption key management may refer to ANSI Χ9.17, Financial Institution Key Management (in its entirety), which is herein incorporated by reference. The technology specified in these standards protects the integrity of transactions against forgery and manipulation.

As shown in Fig. 4, the issuer of the electronic document or the Representative can implement the DAS document verification system on a typical office or laptop computer, having the DAS coding subsystem (PCMCIA card) installed and an electronic digital signature pad used to issue documents signed by hand. . For the operation of the DAS system it is not required to install a hand signature creation device when the digital structure of the document is sufficient. However, today it is typical for parties to a loan or other business transaction to submit laser-printed copies of documents that have been issued by hand. Other components and software typically found in the Representative's terminal are the communication subsystem supporting the transmission of encoded or digitally signed documents to the Verification Center via a modem telephone line or other suitable means of communication, PCMCIA card interface, message handling program, input / output interface, application enabling many messages.

The Verification Center is preferably organized as a server subsystem, a cryptographic security subsystem, and an archiving subsystem. As part of the server subsystem, which may be implemented on a Class 486 computer running a UNIX operating system, the communications subsystem includes a multiport driver (see also Fig. 3) that handles communication with the Representatives' terminals. In addition, in the server subsystem, there are cryptographic key management subsystems, a backup system, a relational database management system, input / output (I / O), and an administrative system. The PCMCIA card and the interface of the communication subsystem of the backup system, together with the backup subsystem mentioned above, can be implemented on a class 486 computer running under the control of a DOS operating system. Interfaces of the communication subsystem of the archiving system at the document archiving facilities or devices mentioned above.

The DAS could also introduce an additional function of the "notarized certification" type. This would require the third party present when issuing the document to have a coding card that it could ensure that in the transaction to be verified later

182 In order, the pages containing or certifying the document to be signed were in fact the correct pages. This additional notarization function is not required, but can be used to further verify the identity of the parties.

Figure 6 is a diagram illustrating a typical DAS application used in the mortgage area where the Representatives are the firm / agent finalizing the loan.

The following steps are performed in the next steps:

step 1. Generation of the complete Certification Issuer code and issue of the card to the parties submitting the documents, establishing a chain of evidence. The parties are equipped so that they can send and receive documents;

step 2. The Bank / Spółka Hipoteczna uploads and electronically sends the documents to the Verification Center, which sends them to the Company / Finalizing Agent;

step 3. The Verification Center sends the documents to the Company / Finalizing Agent;

step 4. The Company / Finalizing Agent has documents issued by the Buyer / Seller certified with an electronic signature;

step 5. The Company / Finalizing Agent provides the Buyer / Seller with a "paper copy" of the signed documents;

step 6. The Company / Finalizing Agent sends the documents to the Verification Center, which places date and time stamps on the issued documents, and then sends them to the Bank / Spółka Hipoteczna. Whenever the Bank / Spółka Hipoteczna needs verified documents, it can search for them immediately in the archives of the Verification Center;

step 7. Bank / Spółka Hipoteczna sends the verified documents to be sent by the certifying issuer to the investor on the secondary market;

step 8. Whenever the investor needs verified documents, he can obtain them immediately from the Verification Center.

In the first step, the certifying issuer finishes generating the code and issues PCMCIA cards for authorized parties, which are used to transfer documents and establish legal and evidence proceedings. Parties, which are basically not individuals but economic and financial institutions such as Banks / Mortgage Companies and Companies / Agents Finalizing the transaction, are equipped in a way that allows sending and receiving documents electronically. Step 2, - The Bank / Spółka Hipoteczna uploads and electronically sends the document to the Verification Center, which sends it to the Company / Finalizing Agent after adding integrity blocks and date and time stamps. In step three, the Verification Center sends the verified loan documents to the Company / Finalizing Agent.

In step four, the Company / Finalizing Agent has documents confirmed by the digital signatures of the Buyer / Seller. In step five, the Company / Finalizing Agent provides the Buyer / Seller with a "paper copy" of the signed documents. In the sixth step, the Company / Finalizing Agent sends the documents to the Verification Center, which adds integrity blocks and date and time stamps of the approved documents, sending the documents to the Bank / Mortgage Company, and stores the documents. Each time the Bank / Mortgage Company needs copies of authentic documents, they can be searched immediately in the archiving system of the Verification Center.

In step seven, the Bank / Spółka Hipoteczna indicates that authentic documents are transferred by the authorizing issuer to Bank Hipoteczny / Investor operating on the secondary market. In step eight, each time the Investor needs authentic documents, they can be found immediately in the Verification Center.

Figure 7 illustrates an example of a document certification process. In the first step, an electronic document is designed that reflects the agreement of the parties, such as the technological operations shown in Fig. 7 by the factory. The electronic document is then entered into the Representative's terminal, which is shown as a laptop having a verified PCMCIA card, optionally, a pad with a pen for registering handwritten signatures. A typical configuration of the Representative's terminal is an office computer or laptop, with a high-resolution display, a PC card reader and a shim with

182 163 with a pen for registering handwritten signatures. As shown in Fig. 7, an electronic document that can be created locally or remotely is displayed on this terminal.

In the second step, the parties to the agreement place their signatures on the document using the pad and the appropriate pen. These signatures are recorded and placed in the appropriate places on the electronic document. After all parties have signed the document, the Representative confirms the completion of the document issuing operation by attaching his or her digital signature and attaching his or her certificate using a PC Card. Should a paper document be needed, the electronic document would be printed first. The paper document would be placed on the clipboard and the terminal cursor would be placed in the right place on the electronic document. This allows handwritten signatures to be uploaded and sent when actually signing the paper document. The electronic version is then an exact duplicate of the paper document.

After local certification, the Representative sends the electronic document to the Verification Center in the third step of the procedure. The Verification Center preferably includes a well-equipped server computer with adequate data storage and backup capability, and is secure and closely guarded. The Verification Center has the ability to digitally sign independently, one or more PC Cards, and the appropriate time pattern. When a digital document is received, the Verification Center checks its authenticity and the authorization of the Representative (step 4). If authentic, the electronic document is time and date stamped (step 5), digitally signed (step 6), registered (step 7), and stored at the Verification Center. Certified copies of the electronic document can then be distributed as instructed by the relevant party, such as the document benefit holder (owner) identified by the document.

The Verification Center maintains an electronic document and a record or history of all transactions, such as requests for copies, and the like, associated with that document. It should be noted that the register is a useful instrument used in many management functions that affect the usability of the system. For example, the use of a register identifying subsequent electronic operations related to the transaction has an impact on the limitations related to the liability of the Verification Center. In addition, the registry is also useful as documentation of a document ownership change chain.

The Verification Center also controls access to the document by following the authorization instructions provided by the owner of the document. Authorization instructions may be updated or changed in line with changes (for example, attachments) to the document's ownership.

Figure 8 illustrates the process of digitally signing a document, shown generally as an "information object", by using a hash function. Generally, a hash function is a real one-way coding function that is performed over the entire length of the information object to be protected. The hash function creates a "message file" such that two different information objects cannot form the same "message file". Since the hash function creates different message sets for information objects that differ by even one bit, it is a powerful tool for checking the integrity of the information object. According to the invention, the message set is encoded using the secret key of the signatory. The combination of the hash function and the coding in this way ensures system integrity (i.e. the ability to detect changes) and traceability (i.e. the ability to determine the identity of the signatory or the relevant party). A digital signature (the encoded message file) is attached to the readable information object (see steps 2 and 6 of Figure 7).

Of the many different hash functions that are known, it is now believed that designated MD4 and MD 5, which are embedded in the systems widely available in the market of the aforementioned vendors, and the published US government hash security algorithm, are

182 163 appropriately strong algorithms that can be used in the applicant's DAS. Of course, other suitable hash functions may emerge over time.

The steps of digitally signing an electronic document (step 2 and 6 of Fig. 7) and verifying the digital signature (step 4 in Fig. 7) are further illustrated in Fig. 9. The electronic document has one or more digital signatures attached to it. using the signing algorithm and the secret key (s) of the signer (s) as described with reference to Figure 8, and the certificate (s) of the signer (s). As described above, each certificate includes the signer's identity information, the signer's public signature / verification key, predetermined additional information about the signer, and a digitally signed certificate message file. The format of the constituent parts of such an X.509 specification certificate that can be used by the user or the Verification Center is shown in Figure 10.

The signature checking step, which is normally but not necessarily performed by the Verification Center, includes decoding the message set attached to the document, reapplying a hash function to the document to obtain the next message set, and comparing the obtained message set with the decoded message set. The public signature / verification key found in the certificate signed by the certifying authority and attached to the document is used to decode the attached message file. If the values ​​of the two message files match, the identity of the person named in the certificate can be considered as the signatory identity of the document or other information object, and the integrity of the document is confirmed and guaranteed. The Verification Center certifies this result by digitally signing the document.

As illustrated in Figure 11, the user (Representative) or even certification issuer certificate is preferably digitally signed in substantially the same way electronic documents are digitally signed, except where the certificate is signed by issuers authorized to create certificates. . Checking digital signatures on documents includes checking the public signatures of all certifying issuers along the path between the signer and the original certifier, who is the highest authority of the certifying issuers. Signatures of certifying issuers are transferred to the signatory's PC card and attached to documents prepared with the use of this card.

As shown in Fig. 12, the path from the signatory to the original certifier may be considered as part of the verification tree. The signer (user) certificate is digitally signed by a Certification Authority whose own certificate (Certification Authority Certificate) is signed by the original Certification Authority. When multiple certifiers are located in different branches of the certification tree, simply search for certifier certificates along both branches until a common node is found to validate the digital signature for an entity in different branches of the verification tree and validate the certificates up to the common node.

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<td>PC CARDS</td><td>TERMINAL SOFTWARE</td><td>SERVICES OF THE DOCUMENT VERIFICATION SYSTEM</td>

<td>THIRD PARTY ACCESS CRYPTOGRAPHY PROVIDES CRYPTOGRAPHY WORKING FOR: PIN CARD ACTIVATION AND RELEASE OF SECRET CRYPTOGRAPHIC MATERIALS, KEY REPLACEMENT THE SET OF MANAGEMENT KEYS CODE. THE MIXER CODING AND AUTHORIZING KEYS ARE STORED BY: INFORMATION CHARACTERIZING THE CARD CERTIFICATES AND KEYS MACRO COMMANDS FOR THE PROGRAM ATTRIBUTE TABLES</td><td>SOFTWARE MANAGING CARD RESOURCES PARTICIPATING IN CARD VERIFICATION AND ACTIVATION FORMATTES DATA AND PERFORMING ENTRY / EXIT OPERATIONS WITH THE CARD. CALLS THE SERVICES ASSOCIATED TO THE CARD</td><td>PIN VERIFICATION INTEGRAL VALUE CALCULATION SYMBOL VERIFICATION SIGNATURE VERIFICATION OF INTEGRITY TIME STAMP ENCODING / DECODING, KEY MANAGEMENT VERIFICATION STORAGE AND AUTHENTICATION ALLOCATION</td>

FIG. 2

182 163

DOCUMENT VERIFICATION SYSTEM

ARCHITECTURE OF THE DOCUMENT VERIFICATION SYSTEM

<img file="PL182163B1_D0001.tif" />

WASH PAD-

<img file="PL182163B1_D0002.tif" />

<img file="PL182163B1_D0003.tif" />

WASHER WASHER-

<img file="PL182163B1_D0004.tif" />

LETTERS OF SIGNATURES

<img file="PL182163B1_D0005.tif" />

<img file="PL182163B1_D0006.tif" />

SIGNATURE FRAME

<img file="PL182163B1_D0007.tif" />

SUBSYSTEM

TERMINAL *

SERVER SUBSYSTEM

CRYPTOGRAPHIC SERVER SECURITY SUBSYSTEM

MPC - MULTIPORT CONTROLLER

PCR - CARD READER PCM / CIA ♦ - LAPTOP COMPUTERS CAN BE USED

CLASS 486/50

FIG. 3

182 163

FUNCTIONAL RELATIONS OF THE DOCUMENT VERIFICATION SYSTEM

DOCUMENT VERIFICATION SYSTEM

CRYPTOGRAPHIC SECURITY SUBSYSTEM

SECURITY SUBSYSTEM

CODING SUBSYSTEM

CODING_ COMMUNICATION SUBSYSTEM__ {PORTO DIAMETER SPEED?

COMMUNICATION SUBSYSTEM

I / O fPORT LOW? TffJLYMO-I MEDIUM SHAFT-I _JB1QWA_

L_K0sa__i

P0DSYS1EMCOMMUNICATION SUBSYSTEM IMMNDNDT KACIA SYSTEM FOR ---------------- ^ LELOPORT CRYPAD SECURITY 'CONTROLLER'

OBSPCM / MESSAGE CIA INTERFACE

<img file="PL182163B1_D0008.tif" />

'CODING SUBSYSTEM [_KĄRTADES_J

THE TERMINAL COMMUNICATION SUBSYSTEM

Jtographic

THE MESSAGE HANDLING PROGRAM SUBSYSTEM

CYCLE ARCHIVING SUBSYSTEM i ---------- I --- 1

I__J. ARCHIVING

AN APPLICATION TO ENTER MULTIPLE MESSAGES

<td>SUBSYSTEM ZA-</td><td>MANAGEMENT SYSTEM</td><td>SUBVS-</td><td>IN</td>

<td>SAFETY</td><td>RELATIONSHIP DATABASE</td><td>ΈΜΚ0Ν CONTROLLING</td><td>Y</td>

<td colspan="3">ADMI SYSTEM SUBSYSTEM-</td><td>D R</td>

<td colspan="3">NISTRATIVE MANAGEMENT</td><td>Π</td>

<td>KEY</td><td colspan="2">1 ENTRY / EXIT</td><td>at K.</td>

TERMINAL SUBSYSTEM

TERMINAL 486/50 PC

MS / DOS

WINDOWS

CUSTOMER PERFORMING CUSTOMER APPLICATIONS

SECURED COMMUNICATION FUNCTIONS

FIG. 4

SERVER SUBSYSTEM

SERVER · 486/50 SYSTEM PRO Dodge

BUILTING AROUND A POWERFUL MULTI-USER RDBMS, PROVIDING COMMUNICATION WITH MULTIPLE TERMINALS WITH FULL CONTROL AND ADMINISTRATION. Sys ™ server ·¹

CRYPTOGRAPHIC 486/50 PC MS / DOS PROVIDES ENCODING

182 163

CONTROL FUNCTIONS OF THE DOCUMENT VERIFICATION SYSTEM CONTROL FUNCTIONS

<td rowspan="2">CONFIDENTIALITY</td><td rowspan="2">INTEGRITY</td><td colspan="2">IRREGULAR (SIGNATURE)</td><td rowspan="2">USER MANAGEMENT RESTRICTIONS</td>

<td>USER1K</td><td>VERIFICATION SYSTEM</td>

<td>PUBLIC PIN KEY AND KEY MATERIAL TRANSACTION DES CODING</td><td>DIGITAL SIGNATURE PROVIDES INTEGRATED SECURITY</td><td>THE DIGITAL SIGNATURE OF THE USER / CUSTOMER SIGNS THE TRANSACTION IN A WAY THAT CANNOT BE REJECTED</td><td>THE DIGITAL SIGNATURE OF THE VERIFICATION SYSTEM SIGNS THE TRANSACTIONS ^ METHOD THAT CANNOT BE REJECTED INTEGRITY BLOCK</td><td>RESTRICTIONS ON USER PROFILE STORED IN THE PCM / CIA CARD</td>

<td></td><td></td><td></td><td>IDATE TIME MARKER</td><td>PIN CARD VERIFICATION, PCM / CIA FOR THE TERMINAL AND DOCUMENT VERIFICATION SYSTEM</td>

FIG. 5

182 163

DOCUMENT VERIFICATION SYSTEM

LOAN TRANSACTION DOCS VERIFICATION SYSTEM

<img file="PL182163B1_D0009.tif" />

182 163

<img file="PL182163B1_D0010.tif" />

TOWED

DOCUMENT

DOC- / / CONFIRM- /

MENT k WASHER FOR \ DONE \ mmiiu

ELECTRO- \ SIGNATURE \ DOCUMENT - NO MANUAL FT MENT

DESIGN-

<img file="PL182163B1_D0011.tif" />

FOR INTRODUCTION

DOCUMENT [OF HAND SIGNATURES

CARD _{3 SPEED}.

MENTU __.___ FOOT FOOTER ιχ)_Κϋ-

<img file="PL182163B1_D0012.tif" />

DIGITALLY SIGNED

<img file="PL182163B1_D0013.tif" />

4. VERIFY SIGNATURE

5. I ADD AND TIME

6. SIGN THE DOCUMENT DIGITALLY

7. SAVE EVENTS IN THE CONTROL LOG

FIG. 7

<img file="PL182163B1_D0014.tif" />

FIG. 8

182 163

<img file="PL182163B1_D0015.tif" />

FIG. 9

CA CERTIFICATE ^WITH PUBLIC KEY ^ | CERTIFICATE * ζ --------- H SIGNATURE ALGORITHM / USER OR PRICE · '^^ | / TRUM VERIFICATION * | VERIFIED IDENTITY |

<td>IDENTITY</td><td>PUBLIC KEY</td><td>SIGNED VALUE</td>

ESTABLISHING AN EVIDENCE PROCESS

FIG. 11

182 163

<img file="PL182163B1_D0016.tif" />

ESTABLISHING THE IDENTITY OF THE PARTY THAT GENERATES A DIGITAL SIGNATURE

FIG. 12

PRESENTATION OF THE CERTIFICATE Χ509 OF THE CERTIFYING USER OR EXHIBITOR

<td>IDENTITY SURNAME / ORGANIZATION</td><td>VARIOUS ATTRIBUTES</td><td>PUBLIC KEY DECODING INFORMATION</td><td rowspan="2">VALUE SIGNED DIGITALLY SIGNED MESSAGE COLLECTION CERTIFICATES- FICATES</td>

<td colspan="3"></td>

FIG. 10

182 163

DOCUMENT VERIFICATION SYSTEM (DA S)

AUTHENTICATION ALLOCATION BY PCM / CIA CARD AND DATA CODING STANDARD (DES)

<img file="PL182163B1_D0017.tif" />

FIG. 1

Publishing Department of the Polish Patent Office. Circulation of 60 copies

Price PLN 4.00.