Patent Application
20090210714
The present application hereby claims priority under 35 U.S.C. §119 on European patent application number EP 08001230 filed Jan. 23, 2008, the entire contents of which is hereby incorporated herein by reference.
Embodiments of the invention are generally related to supporting easy signature by authors, e.g. medical professionals, who want to authenticate authorship of or validate electronic documents and for verification of such signatures by readers who want to validate content of such electronic documents.
In a classical “offline” scenario according to the prior art based on conventional paper, authors ink-sign documents after validating them. Such documents may then be stored locally or sent to parties trusting that signature. Trust of ink-signatures decreases in a larger community, because some ink-signature typically is not well-known in a large community. Currently, according to another prior art, secure “smartcards” with keys and algorithms on-card are being designed to allow for electronically signing documents on the client-side. Specialized trusted hardware at the client side is needed to maintain end-to-end-security in the smart-card scenario.
In at least one embodiment, the present invention aims at an improvement of this situation.
According to at least one embodiment of the present invention, established device(s)/method(s) of communication (e.g. mobile phones) used for secure communication replace dedicated client -side IT-systems for the authentication of validated documents. It is assumed that e.g. a medical professional—acting as an author of medical documents—operates a mobile phone which is serviced by some mobile phone service provider, such that the medical professional is a registered client of the mobile phone service provider. Instead of mobile phones, similar mobile communication devices can be used by our scheme. A standardized resource locator, i.e. e.g. a storage address or a so called “uniform resource locator” (URL), used e.g. in the http-protocol, may be used to identify and locate a document.
In cases where these electronic documents are stored decentrally, an example embodiment of the invention suggests to store document references and signatures together in a central registry.
At least one embodiment of the proposed invention suggests to use a communication device—preferably a mobile communication device—for signing electronic documents and makes use of the trust that is already established between the corresponding communication service provider and the e.g. medical authors being clients of such a provider.
According to an example embodiment of the invention, a trusted central or centralized registry is used to verify the signatures instead of the reader, who is just given a “confirm/deny” information on his verification requests.
In the following, the invention is described in more detail by help of some figures and example embodiments.
Various example embodiments will now be described more fully with reference to the accompanying drawings in which only some example embodiments are shown. Specific structural and functional details disclosed herein are merely representative for purposes of describing example embodiments. The present invention, however, may be embodied in many alternate forms and should not be construed as limited to only the example embodiments set forth herein.
Accordingly, while example embodiments of the invention are capable of various modifications and alternative forms, embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that there is no intent to limit example embodiments of the present invention to the particular forms disclosed. On the contrary, example embodiments are to cover all modifications, equivalents, and alternatives falling within the scope of the invention. Like numbers refer to like elements throughout the description of the figures.
It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of example embodiments of the present invention. As used herein, the term “and/or,” includes any and all combinations of one or more of the associated listed items.
It will be understood that when an element is referred to as being “connected,” or “coupled,” to another element, it can be directly connected or coupled to the other element or intervening elements may be present. In contrast, when an element is referred to as being “directly connected,” or “directly coupled,” to another element, there are no intervening elements present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between,” versus “directly between,” “adjacent,” versus “directly adjacent,” etc.).
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments of the invention. As used herein, the singular forms “a,” “an,” and “the,” are intended to include the plural forms as well, unless the context clearly indicates otherwise. As used herein, the terms “and/or” and “at least one of” include any and all combinations of one or more of the associated listed items. It will be further understood that the terms “comprises,” “comprising,” “includes,” and/or “including,” when used herein, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
It should also be noted that in some alternative implementations, the functions/acts noted may occur out of the order noted in the figures. For example, two figures shown in succession may in fact be executed substantially concurrently or may sometimes be executed in the reverse order, depending upon the functionality/acts involved.
Spatially relative terms, such as “beneath”, “below”, “lower”, “above”, “upper”, and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, term such as “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein are interpreted accordingly.
Although the terms first, second, etc. may be used herein to describe various elements, components, regions, layers and/or sections, it should be understood that these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are used only to distinguish one element, component, region, layer, or section from another region, layer, or section. Thus, a first element, component, region, layer, or section discussed below could be termed a second element, component, region, layer, or section without departing from the teachings of the present invention.
At least one embodiment of the present invention uses, for example, established encryption schemes, either symmetric or asymmetric. A typical scenario could be like this:
A medical professional registers himself with the trust center (TC) or trusted registry (TR) acting on behalf of and/or operated by the mobile communication service provider. According to an embodiment of the present invention, the trust center (TC) or trusted registry (TR) generates a pair of keys (“private key, public key”) and associates the private key with the mobile-phone identity (IMEI, SIM-chip-number or phone number) in a secret table stored at the TC or TR. The TC or TR also associates the public key with the medical author's name (plus office address) as an entry into a directory.
As shown in
According to one example embodiment of the present invention, an example embodiment of the invention may be implemented in a method for electronically signing electronic documents comprising the following steps:
A) a first communication device (comdev1) is used to
A1) select an existing document (e-doc) to be signed, the document being stored on a storage device (stodev) or to
A2) upload a document (e-doc) to be signed to a storage device (stodev) and to
A3) submit or cause the storage device or a processor unit associated with that storage device to submit a resource locator (RL) uniquely identifying this document (e-doc) to a trust center (TC), where the user (USER) of a second communication device (comdev2) is registered;
B) this second communication device (comdev2)—which may be identical to the first communication device (comdev1)—is then used to
B1) authenticate the user (USER) as authorized to electronically sign at least some electronic documents and to
B2) cause the trust center (TC) to sign the selected or uploaded document with the electronic signature of this user;
C) a signature (sigdoc) of this document (e-doc) is then created by the trust center (TC) by help of a key associated with this user;
D) by the trust center, the signature (sigdoc) is then associated with the document (e-doc) to be signed as the user's signature of this document.
According to another example embodiment of the present invention, an example embodiment of the invention may be implemented in a method for electronically signing electronic documents comprising the following steps:
A) a first communication device (comdev1) is used to
A1) select an existing document (e-doc) to be signed, the document being stored on a storage device (stodev) or to
A2) upload a document (e-doc) to be signed to a storage device (stodev) and to
A3) submit or cause the storage device or a processor unit associated with that storage device to submit a resource locator (RL) uniquely identifying this document (e-doc) to a trust center (TC), where the user (USER) of a second communication device (comdev2) is registered;
B) this second communication device (comdev2)—which may be identical to the first communication device (comdev1)—is then used to
B1) authenticate the user (USER) as authorized to electronically sign at least some electronic documents and to
B2) cause the trust center (TC) to create a digest (docdig) of the document (e-doc) to be signed and to
B3) send the generated digest to the second communication device (comdev2);
C) a signature (sigdoc) of this digest (docdig) is then created by the second communication device (comdev2) by help of a key associated with this user, stored locally on this second communication device (comdev2);
D) the signature (sigdoc) is then sent back to the trust center (TC) and there associated with the document (e-doc) to be signed as the user's signature of this document.
As shown in
A) a third communication device (comdev3)—which may be identical to the first communication device (comdev1) and/or the second communication device (comdev2)—is used to
A1) select an existing document (e-doc), the signature of which is to be verified, and to
A2) submit a signature verification request command (svrc) to a trust center (TC) where the owner of the signature to be verified is registered;
B) the signature is then decrypted by the trust center and
C) information (verinf) is submitted to the originator (orig) of the request (svrc) allowing the originator to verify the signature.
The process of generating table entries with signature keys is shown in
According to an alternative embodiment of the present invention the author's mobile phone is used to hold his private key: Instead of managing a secret table with private keys, the TC or TR might as well send back the generated private key to the mobile communication device of the medical author. In that case, the security requirements for the TC or TR are lowered and the list of “Keys and Authors” may be a public directory. This embodiment is illustrated in
At another (e.g. later) instance in time, the registered (e.g. medical) author may want to upload a document to the storage location accessible to other (not necessarily registered) readers. For this purpose, as shown in
At any later instance in time, the medical author may want to view the uploaded document and eventually validate the content. This situation is illustrated in
At any later instance in time, the registered medical author may want to authenticate authorship/reviewership of some centrally or decentrally stored document which he validated. He therefore—according to an example embodiment of the present invention—sends the document (i.e. uses e.g. a URL to instruct the central storage to send the document on his behalf) to the trust center (TC). There a digest—a number specifically depending on the content of the document—is generated and encrypted using the private key of the medical professional and—in encrypted form—sent back to the central storage where it will be attached to the document as a signature (together with specifications of the trust center (TC) and the algorithms used). This situation is illustrated in
At any (possibly) later instance in time, the registered medical author may want to “sign a document”, i.e. state his authorship/reviewership of some identified/located document which he validated and therefore sends the document′ RL (i.e. a URL) to the trusted registry (TR), which loads that document and creates a digest—a number specifically depending on the content of the document—and asks the client's mobile device to encrypt that digest using the private key of the medical professional and registers a new record (consisting of the URL, the encrypted digest as well as the plaintext (i.e. unencrypted) digest plus possibly some useful search attributes) to be inserted into the registry's reference list.
Registered (medical) authors may (
Therefore there are at least two alternative implementations of embodiments of the present invention, one using the author's mobile phone to hold his private key. In this case, instead of encrypting the digest using the author's private keys, the TC or TR will send the generated digest to the mobile communication device of the medical author, which then responds with the encrypted form of the digest using the private key stored locally on the mobile communication device.
According to another alternative implementation, even the digest creation algorithm may be operated on the mobile device, e.g. in cases where the document is available locally (at the medical author's site) and its whole signature is generated (by creating a digest and encrypting that digest) by the mobile device, which then sends the signed document together with its URL (or another suitable identifier/locator or address) to the (e.g.) central storage. This situation is illustrated in
At any later instance of time and at the discretion of the trusted registry (TR), the records in the registry may be used to verify the signature against the document storage, in order to exclude a compromised communication link or a compromised decentralized storage. For that purpose, as e.g. shown in
At any later instance in time, some reader may want to verify authorship/reviewership of the specified, named author/reviewer of some registered or centrally stored document and therefore
sends the documents resource locator (e.g. the URL) to the trusted registry (TR)
or
sends the document (i.e. uses the URL to instruct the central storage to send the document on his behalf) to the trust centre,
where a digest—specifically depending on the content of the document—is generated and compared to the
the digest (i.e. the plain text form of the signature) also attached to the document referenced by the registry
or
the decrypted form of the signature (using the public key of the specified medical author for decryption) attached to the document returned by the central storage. This situation is shown in
The TC or TR will report (confirm/deny), whether the signature is valid, which is true if and only if the decrypted (decrypt) signature (docsig) matches the digest (docdig). Any reader may perform this sequence of steps as a single command on any identified/located document with such a signature.
According to another embodiment of the invention, there is an alternative using symmetric keys: Since the TC never releases the public keys of registered medical authors, they may as well be identical to the private key used for encryption. Thus, symmetric encryption—with the same key used for encrypting and decrypting—may be used as well in this scheme. The only difference to the trust center (described above) will be, that a single key is generated and inserted into the only table of keys in the TC. Both generation and verification of the signature is done within the TC and with the same key. The “symmetric” scheme does, however, exclude the “private key on mobile device” variant, because the trust center has anyway the highest security requirements in this case. Brute force attacks against the keys have, however, to be avoided using dedicated measures in the TC, since attacking the “decryption key” in this scheme harms the “encryption key” at the same time.
Some embodiments of this invention are especially suitable for cases, in which the data stored (e.g. in some decentralized storage) or the data uploaded, i.e. the document, is not authored by the one who signs it, but is authored by some third party (e.g. assistant, nurse, patient, other person) or by some automatic sender that stores or uploads unvalidated (“raw”) data. In some of these cases, the invention proposes that the (medical) “authorizer” just validates the content of the data by looking at it as it is already stored on the (central or decentralized) storage server and then signs it using the methods proposed above.
At least one embodiment of the invention also covers the case, where—instead of mobile phones—other IT-devices with sender/receiver-functionality are used by the (medical) author or signer, provided these devices have a unique communication identity (such as IP internet address, SIM chip number, telephone ENUM or, IMEl or similar address) and provided this communication identity is linked to a registered entity (as owner or User: “medical author”).
It can be easily inferred from the above disclosure of embodiments of the present invention, that important advantages of at least one embodiment of the present invention or at least some respective embodiments of this invention are as follows:
a medical professional's identity is provided without extra hardware (cell phone/SIM access provider);
only few assumptions are necessary about client's information technology equipment;
simple and existing software can be used to implement the invention, hardware and protocols are combined to support esignature;
higher availability may be achieved when compared to complex telematics IT-systems and health cards;
storage Server(s) may be separated from signature generation/verification;
content source(s) may be separated from the communication service provider;
content source(s) may be separated from signature generation/verification;
a central registry may be used for managing decentralized storage of documents;
only secure places for the generation of a digest are needed;
each private key may be restricted to be always kept with the (medical) client;
the technical signature-to-documents verification will be separated from the reader's signature request.
Further, elements and/or features of different example embodiments may be combined with each other and/or substituted for each other within the scope of this disclosure and appended claims.
Still further, any one of the above-described and other example features of the present invention may be embodied in the form of an apparatus, method, system, computer program and computer program product. For example, of the aforementioned methods may be embodied in the form of a system or device, including, but not limited to, any of the structure for performing the methodology illustrated in the drawings.
Even further, any of the aforementioned methods may be embodied in the form of a program. The program may be stored on a computer readable media and is adapted to perform any one of the aforementioned methods when run on a computer device (a device including a processor). Thus, the storage medium or computer readable medium, is adapted to store information and is adapted to interact with a data processing facility or computer device to perform the method of any of the above mentioned embodiments.
The storage medium may be a built-in medium installed inside a computer device main body or a removable medium arranged so that it can be separated from the computer device main body. Examples of the built-in medium include, but are not limited to, rewriteable non-volatile memories, such as ROMs and flash memories, and hard disks. Examples of the removable medium include, but are not limited to, optical storage media such as CD-ROMs and DVDs; magneto-optical storage media, such as MOs; magnetism storage media, including but not limited to floppy disks (trademark), cassette tapes, and removable hard disks; media with a built-in rewriteable non-volatile memory, including but not limited to memory cards; and media with a built-in ROM, including but not limited to ROM cassettes; etc. Furthermore, various information regarding stored images, for example, property information, may be stored in any other form, or it may be provided in other ways.
Example embodiments being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the present invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 08001230 | Jan 2008 | EP | regional |
| EP08001229 | Jan 2008 | EP | regional |
