US6061789A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Secure anonymous information exchange in a network
Assignee: Google LLC
•
Filing: 1996-01-12
•
Granted: 2000-05-09
•
Expires: 2016-01-12
Abstract
Abstract PCT No. PCT/IB96/00025 Sec. 371 Date Jul. 2, 1998 Sec. 102(e) Date Jul. 2, 1998 PCT Filed Jan. 12, 1996 PCT Pub. No. WO97/25801 PCT Pub. Date Jul. 17, 1997Computer network management for electronic commerce requires technical implementations of business processes. The process addressed here is a technical method for a communication in which two or more parties legitimately want to communicate anonymously, often before discussing a deal or closing a business, e.g. for anonymous bidding or auctioning in electronic commerce. Essentially, the invention is a method, described by a protocol, for safely exchanging data in a network that provides a public key infrastructure and an anonymous communication possibility between network users. It consists of a sequence of steps in which both sender (e.g. customer) and addressee (e.g. merchant) compose data sets (i.e., requests and replies) that are based on received data and/or prior knowledge. The data sets are enciphered to provide anonymity, and digitally signed to provide proof of the partner. The invention is also a system designed to implement the invented method.
Inventors
- 👤 Ralf Ch. Hauser
- 👤 Gene Tsudik
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 21:37
CPC Classifications
G; G06; G06Q; G06Q20/00; G06Q20/38; G06Q20/388; G06F; G06F21/00; G06F21/60; G06F21/606; G06Q20/08; G06Q20/12; H; H04; H04L; H04L9/00; H04L9/32; H04L9/3247; H04L9/3263; H04L9/3271; H04L9/3273; G06F2221/00; G06F2221/21; G06F2221/2103; H04L2209/00; H04L2209/42
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
210 words
A method for anonymous, provable information exchange between a sender and an addressee in a computer network, the computer network providing a public key infrastructure, preferably with certification, and an anonymous communication channel available between network users, said method comprising the following steps: said sender C composes an offer request REQ with a subject or merchandise description MD and a digital signature SIG-c of C, REQ=(MD,SIG-c), said REQ is transmitted via said anonymous communication channel to at least one addressee M, said addressee M composes a reply REP with an offer description OD and its digital signature SIG-m, said digital signature SIG-m being computed over a selection of quantities comprising at least one of MD, OD, SIG-c, REP=(OD, SIG-m), and further including M's public key PK-m or public key certificate Cert-m, said sender C, upon receiving said reply REP, uses M's public key PK-m, known, transmitted, or extracted from said public key certificate Cert-m, to encrypt said received SIG-m, thus determining a first temporary value TMP-1, TMP-1=PK-m(SIG-m), said sender C computes a concatenation of said selection of quantities on which said signature SIG-m is based, thus determining a second temporary value TMP-2 TMP-2=H(SIG-c/MD/OD), said sender C compares said temporary values TMP-1 and TMP-2, a match indicating genuineness of said offer.
Claim 2
Independent Claim
210 words
A method for anonymous, provable information exchange between a sender and an addressee in a computer network, the computer network providing a public key infrastructure, preferably with certification, and an anonymous communication channel available between network users, said method comprising the following steps: said sender C composes an offer request REQ with a subject or merchandise description MD and a digital signature SIG-c of C, REQ=(MD,SIG-c), said REQ is transmitted via said anonymous communication channel to at least one addressee M, said addressee M composes a reply REP with an offer description OD and its digital signature SIG-m, said digital signature SIG-m being computed over a selection of quantities comprising at least one of MD, OD, SIG-c, REP=(OD, SIG-m), and further including M's public key PK-m or public key certificate Cert-m, said sender C, upon receiving said reply REP, uses M's public key PK-m, known, transmitted, or extracted from said public key certificate Cert-m, to encrypt said received SIG-m, thus determining a first temporary value TMP-1, TMP-1=PK-m(SIG-m), said sender C computes a concatenation of said selection of quantities on which said signature SIG-m is based, thus determining a second temporary value TMP-2 TMP-2=H(SIG-c/MD/OD), said sender C compares said temporary values TMP-1 and TMP-2, a match indicating genuineness of said offer.
Claim 3
Dependent Claim
29 words
The method according to claim 1, wherein the digital signature SIG-c of the sender C is a hash function of the MD and/or a randomly generated nonce R-c, SIG-c=H(MD/R-c).
Claim 4
Dependent Claim
31 words
The method according to claim 1, wherein the digital signature SIG-c of the sender C is an encryption of the MD under a randomly generated nonce R-c as key, SIG-c=R-c(MD). 4.
Claim 5
Dependent Claim
35 words
The method according to claim 1, wherein the digital signature SIG-c of the sender C is a hash function of the MD and/or a randomly generated nonce R-c, encrypted under C's secret key SK-c, SIG-c=SK-c[H(MD/R-c)].
Claim 6
Independent Claim
62 words
The method according to any of the claims 2 to 4, wherein the nonce R-c of sender C is transmitted to the addressee M, the addressee M computes a hash function of said MD and R-c, thus determining a third temporary value TMP-3, TMP-3=H(MD, R-c), said addressee M compares said temporary value TMP-3 and SIG-c, a match indicating genuineness of said SIG-c.
Claim 7
Dependent Claim
47 words
A method according to claim 5, wherein the addressee uses PK-c, either known, received, or extracted from Cert-c, to encrypt the received SIG-c, thus determining a fourth temporary value TMP-4, TMP-4=PK-c(SIG-c), said addressee compares said temporary values TMP-3 and TMP-4, a match indicating genuineness of said SIG-c.
Claim 8
Dependent Claim
53 words
The method according to claim 1, wherein the digital signature SIG-m of the addressee M is a hash function of the chosen selection of quantities of MD, OD, SIG-c, SIG-m=H(SIG-c/MD/OD), and the concatenation to derive TMP-2 is a hash function of said same selection of quantities used to compute said SIG-m, TMP-2=H(SIG-c/MD/OD). 8.
Claim 9
Independent Claim
41 words
The method according to any of the claims 2 to 4, wherein the digital signature SIG-m of the addressee M is a hash function of the chosen selection of quantities of MD, OD, SIG-c, encrypted under M's secret key SK-m, SIG-m=SK-m(H(SIG-c/MD/OD)).
Claim 10
Dependent Claim
40 words
The method according to claim 1, wherein, the sender has an a priori knowledge of the addressee's public key PK-m, and the addressee M encrypts the offer description OD with its secret key SK-m and transmits a reply REP=(SK-m(OD), SIG-m).
Claim 11
Dependent Claim
23 words
The method according to claim 1, wherein the sender C further transmits its user identification ID-c to the addressee M as identity proof.
Claim 12
Independent Claim
36 words
The method according to any of the claims 2 to 4, wherein the sender C further transmits the nonce R-c to the addressee M, enabling identification of said sender C by verification of its signature SIG-c.
Claim 13
Dependent Claim
31 words
The method according to claim 1, wherein the sender C and/or the addressee M are keeping state in that at least one of them stores incoming requests REQ and/or replies REP.
Claim 14
Independent Claim
228 words
A system for anonymous, provable information exchange between a sender and an addressee in a computer network, the computer network providing a public key infrastructure, preferably with certification, and an anonymous communication means between network users, said system comprising: means in said sender C for composing an offer request REQ=(MD, SIG-c) with a subject or merchandise description MD and a digital signature SIG-c of C, means for making said offer request REQ anonymous, means for transmitting said anonymous offer request to at least one addressee M, means in said addressee M for composing a reply REP=(OD, SIG-m) with an offer description OD and a digital signature SIG-m of M, said digital signature SIG-m being computed over a selection of quantities comprising at least one of MD, OD, SIG-c, and further including M's public key PK-m or public key certificate Cert-m, means in said sender C, upon receiving said reply REP, for encrypting said received SIG-m and determining a first temporary value TMP-1=PK-m(SIG-m), using M's public key PK-m, known, transmitted, or extracted from said public key certificate Cert-m, means for computing a concatenation of said selection of quantities on which said signature SIG-m is based and determining a second temporary value TMP-2=H(SIG-c/MD/OD), means in said sender for comparing said first and said second temporary values TMP-1 and TMP-2, a matching of TMP-1 and TMP-2 indicating genuineness of said offer.
Claim 15
Independent Claim
228 words
A system for anonymous, provable information exchange between a sender and an addressee in a computer network, the computer network providing a public key infrastructure, preferably with certification, and an anonymous communication means between network users, said system comprising: means in said sender C for composing an offer request REQ=(MD, SIG-c) with a subject or merchandise description MD and a digital signature SIG-c of C, means for making said offer request REQ anonymous, means for transmitting said anonymous offer request to at least one addressee M, means in said addressee M for composing a reply REP=(OD, SIG-m) with an offer description OD and a digital signature SIG-m of M, said digital signature SIG-m being computed over a selection of quantities comprising at least one of MD, OD, SIG-c, and further including M's public key PK-m or public key certificate Cert-m, means in said sender C, upon receiving said reply REP, for encrypting said received SIG-m and determining a first temporary value TMP-1=PK-m(SIG-m), using M's public key PK-m, known, transmitted, or extracted from said public key certificate Cert-m, means for computing a concatenation of said selection of quantities on which said signature SIG-m is based and determining a second temporary value TMP-2=H(SIG-c/MD/OD), means in said sender for comparing said first and said second temporary values TMP-1 and TMP-2, a matching of TMP-1 and TMP-2 indicating genuineness of said offer.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-05-09 | 2003-11-08 | 2004-05-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-05-09 | 2007-11-08 | 2008-05-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-05-09 | 2011-11-08 | 2012-05-09 | $7700.00 | Window Closed / Lapsed |