Patent Application
20070104323
The invention disclosed herein relates generally to processing of mail pieces, and more particularly to methods and systems for maintaining the sender's address, i.e., return address, of a mail piece private from unauthorized parties.
The United States accounts for the largest domestic letter traffic in the world, handling almost 200 billion pieces of mail each year. Many companies and private concerns use the mailing system to provide advertising information to customers or potential customers, and solicit information and responses from customers or potential customers. A few examples of the way the mail system is utilized includes, for example, advertising catalogues, sales brochures, and the like, subscription or potential business solicitations, information request responses, proxy statement responses, remittance documents (invoices for payment due) and the like.
Mail pieces are typically provided with the name and address of the sender, i.e., a return address or origination address, in clear text such that the return address is easily readable. Thus, any party that handles the mail piece can easily determine the sender of the mail piece. In many instances, knowing the sender of the mail piece provides enough information to determine the likely contents of a mail piece, such as, for example, bills, payments, credit card information, bank account information, personal items, etc. Thus, if the mail piece is inadvertently delivered to an incorrect recipient and the contents of the mail piece can be discerned based on the sender, there is the potential for a loss of privacy for the intended recipient. Additionally, the ability to discern the contents of a mail piece based on the sender can allow potential thieves to selectively remove mail pieces that may have valuable or important information from mail boxes easily and quickly, without the need to carefully examine each mail piece or take every mail piece from the mail box. Of course, these problems could be avoided by not providing any sender information on mail pieces. This results, however, in the inability of mail pieces that are undeliverable as addressed to be returned to the sender, as well as negating other benefits of having an identified sender, and therefore is not an acceptable solution.
Thus, there exists a need for methods and systems for keeping information related to the sender of a mail piece private, while still allowing authorized parties, e.g., the intended recipient, the postal authority, etc. to easily obtain the sender information if desired.
The present invention alleviates the problems associated with the prior art and provides methods and systems for keeping information related to the sender of a mail piece private, while still allowing authorized parties to easily obtain the sender information if desired.
According to embodiments of the invention, the sender information for a mail piece is encrypted utilizing an identity-based encryption (IBE) scheme. The encryption key used to encrypt the sender information can be computed using recipient information, e.g., recipient address or some portion thereof, preferably combined with other information available to the recipient to contribute to uniqueness of each mail piece, e.g., date of mailing, etc. The resulting encrypted sender information is printed on the mail piece, preferably in a machine readable format. Thus, the sender information is kept private except for those parties capable of obtaining the corresponding decryption key required to decrypt the sender information. The corresponding decryption key can only be obtained from a trusted third party acting as a Private Key Generator (PKG). A party seeking to obtain a corresponding decryption key must first authenticate itself to the PKG, and upon proper authentication, the PKG will generate the corresponding decryption key based on the encryption key used to encrypt the sender information. If a party is unable to satisfactorily authenticate itself to the PKG, the PKG will not provide the corresponding decryption key. Thus, only those parties authorized to have access to the sender information will be provided with the corresponding decryption key. The corresponding decryption key can then be used to decrypt the sender information into human readable form.
Therefore, it should now be apparent that the invention substantially achieves all the above aspects and advantages. Additional aspects and advantages of the invention will be set forth in the description that follows, and in part will be obvious from the description, or may be learned by practice of the invention. Moreover, the aspects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
The accompanying drawings illustrate presently preferred embodiments of the invention, and together with the general description given above and the detailed description given below, serve to explain the principles of the invention. As shown throughout the drawings, like reference numerals designate like or corresponding parts.
In describing the present invention, reference is made to the drawings, where there is seen in
The sender system 12 prepares a mail piece 20 for sending to a recipient system 14 utilizing a control unit 22, such as a computer processor or the like, that utilizes code stored in the memory 24 to control operation thereof. An input/output device (I/O) 26 can be used to provide additional inputs for generating the mail piece 20. The mail piece 20 includes at least the encrypted name and/or address of the sender 12 (e.g., return or origination address) generated according to the present invention as described below, which is preferably printed by the printer 28 on the mail piece 20 or a label for affixing to the mail piece 20. Optionally, the address of the recipient can also be printed by the printer 28. A delivery system 18, such as, for example a postal authority or private carrier, delivers the mail piece 20 to the recipient.
The recipient system 14 preferably includes a device that will allow the recipient to decrypt the encrypted return address on the mail piece 20 if so desired. The device could be, for example, a personal computer or the like that includes a control unit 32, such as a processor or the like, that utilizes code stored in the memory 34 to control operation thereof. An input/output device (I/O) 36 can be used to provide input/output signals from/to the recipient system 14. Optionally, a scanner 38 can be provided to scan the mail piece 20 if information on the mail piece 20 is provided in a machine readable format.
The PKG 16 provides a public-key cryptosystem utilized to encrypt/decrypt the return address of the mail piece 20. PKG 16 is preferably a trusted party, such as, for example, a reliable and reputable commercial entity or governmental entity. PKG 16 can be, for example, the postal authority or other service provider that typically provides secure services for the postal authority. Public-key cryptosystems allow two people to exchange private and authenticated messages without requiring that they first have a secure communication channel for sharing private keys. In a public-key cryptosystem, each person has a unique pair of keys: a private key that is a secret and a public key that is widely known. This pair of keys has two important properties: (1) the private key cannot be deduced from knowledge of the public key and the message, and (2) the two keys are complementary, i.e., a message encrypted with one key of the pair can be decrypted only with the complementary key of the pair. In one particular type of public-key cryptosystem, a person's public key can be computed from a public identifier associated with the person, such as, for example, the person's name, street address, e-mail address, telephone number, office address, or any combination thereof. Because the public key is a function of only the person's pre-existing public identifier rather than a key produced from a random seed, this kind of public-key cryptosystem is called an identity-based encryption (IBE) scheme. One implementation of an IBE scheme is described in detail in U.S. Published Patent Application No. 2003/0081785 A1, the disclosure of which is incorporated herein by reference.
The present invention utilizes an identity-based encryption scheme to provide privacy of a mail piece sender's name and/or address. The preferred IBE scheme utilized to implement the present invention is described in detail in the aforementioned U.S. Published Patent Application No. 2003/0081785 A1, although other similar IBE schemes may also be used. The preferred IBE scheme utilizes public keys that each consists of an arbitrary string derived from one or more identity related parameters for the intended recipient of a mail piece 20. PKG 16 has knowledge of a secret master key and utilizes a control unit 42, such as a processor or the like, to generate a corresponding private key for each given public key as described below. The PKG 16 performs a setup procedure to generate a master secret parameter 46 and system parameters 48 associated with the specific encryption/decryption algorithm utilized to encrypt/decrypt information. The master secret parameter includes, for example, some integer known only to the PKG 16. The system parameters include, for example, elliptic curve parameters with specific points on the curve used in the encryption algorithm, and are made publicly available for use as described below. The master secret parameter 46 and system parameters 48 can be stored in the memory 44. The master secret parameter 46 and system parameters 48 are used by the control unit 42 of PKG 16 to generate corresponding decryption keys as described below. The system parameters 48 are also used by the sender 12 in encrypting the return address for the mail piece 20 as described below.
The operation of the system 10 will be described with respect to
In step 86, the key formed in step 84 is used to encrypt the return address information of the mail piece 20, e.g., the name and/or address of the sender. The encryption is preferably performed using a known public encryption algorithm that can be part of an application being run by the control unit 22, such as, for example, a mail piece preparation application. The encryption algorithm utilizes the key formed in step 84 along with the system parameters 48 generated by the PKG 16 to encrypt the return address information. Preferably, the system parameters 48 of the encryption algorithm used by the control unit 22 are stored in the memory 24 of the sender system 12 (as illustrated by the dotted line in
Since the return address information for the sender of mail piece 20 is encrypted, the return address information for the sender remains private except for those parties that can decrypt the information. Decryption of the return address information requires the use of a corresponding decryption key, also referred to herein as the private key.
In step 104, it is determined by the PKG 16 if authentication is successful. If not, then in step 106 a failed authentication message is returned to the recipient system 14, and no further action is taken by the PKG 16. If authentication is successful in step 104, then in step 108 the PKG 16 preferably provides an indication of successful authentication to the recipient system 14 and the recipient-based information, along with the salt (if used) that was used as the public key to encrypt the return address information is provided to the PKG 16 by the recipient system 14. This can be performed by scanning the mail piece 20, using the scanner 38, and reading the recipient-based information and salt (if used) used to encrypt the return address information. Alternatively, this information can be read from the mail piece 20 and manually input via the I/O device 36. The control unit 42 of the PKG 16, upon receiving the information in step 108, will then in step 110 generate the corresponding private key based on the recipient-based information and salt (if used) used to compute the public key used to encrypt the return address information utilizing the master secret parameter 46 and system parameters 48 stored in the memory 44. Since as noted above the public key used to encrypt the return address information is preferably different for every mail piece, the corresponding private keys that enable the return address information to be decrypted will also be different for every mail piece. Thus, the private key required for one mail piece will not be able to be used on any other mail pieces as long as the public keys are different.
Alternatively, if the information used as the encryption key is standardized and therefore can be predicted, e.g., the recipient's 11 digit zip code and date of mailing are always used as the encryption key, a user can obtain any number of decryption keys for future use, thereby removing the need to contact the PKG 16 each time it is desired to decrypt the return address information.
In step 112, the generated private key is sent to the control unit 32 of the recipient system 14. The generated private key can be sent using a secure channel, therefore protecting the confidentiality of the private key is desired. In step 114 the control unit 32 of the recipient system 14 uses the received private key to decrypt the return address information on the mail piece 20. The decrypted return address information, in human readable form, can then be output using the I/O device 36. Thus, although the return address information on the mail piece 20 is kept secret, a recipient using the recipient system 14 is able to determine the return address information if desired.
It should be noted that while
Thus, according to the present invention, a method and system for keeping information related to the sender of a mail piece private, while still allowing authorized parties to easily obtain the sender information if desired, is provided. While preferred embodiments of the invention have been described and illustrated above, it should be understood that these are exemplary of the invention and are not to be considered as limiting. Additions, deletions, substitutions, and other modifications can be made without departing from the spirit or scope of the present invention. Accordingly, the invention is not to be considered as limited by the foregoing description but is only limited by the scope of the appended claims.
