2-Dimensional Key (2D key) and Multihash Key
Purpose of this File:
This file promotes the 2D key and multihash key.
To go back to the guide, click here.
 Patent licensing of 2-dimensional key (2D Key).
 Patent licensing of multihash key.
 Copyrighted software and copyright licensing of 2-dimensional key (2D Key).
 Copyrighted software and copyright licensing of multihash key.
2D Key is a method and system to create big and yet memorizable secret beyond the current prior art technologies using the single-line password/key input field at 128 bits to 256 bits or more. Multihash Key uses key strengthening (aka hash iteration) and hash truncation to create multiple unique slave keys from a master key for both the offline and online accounts. The slave key from bigger hash iteration round has stronger security than the slave key from smaller hash iteration round. Consequently, the security, usability generally and memorizability particularly, can be improved by the hybrid combination of 2D Key and Multihash Key. For more information, please refer to the manual of this software. For a list matching the hash round/iteration number with the offline/online accounts, download here.
For private key optimization of 192-bit Mobile ECC software, when this software is used together with 2D key input method, there is a memory optimization to minimize the memorizable size of private key. Firstly, a 128-bit 2D secret is created using 2D key to act as the token password in the 2-factor multimedia key method. Secondly, an at least 192-bit multimedia data file can be used as software token to be encrypted and stored in a USB flash drive as token ciphertext. The token password (i.e. 2D key secret) and token plaintext, after the optional processes of multihash key, can generate a secret to act as a 192-bit private key secret in the 192-bit Mobile ECC. Whenever there is a need, get the USB flash drive storing the token ciphertext, decrypt it using the token password (i.e. 2D key secret), and select the hash iteration of multihash key to create a slave key.
To know more about its operations, please download and read the user manual.
Advantages & Disadvantages:
 Memorizability/Mnemonic problem of multiple passwords for multiple accounts has been solved.
 Mobility is another added good feature.
 Up to 128 replacers for password changing per slave key.
 Weaknesses are its possible threats subject to keylogging, hacking, and shoulder-surfing attacks, just like the current password technologies in the present days.
 There exists a one-step error from version 3.0 to version 4.0. Hash round (N) in version 3.0 is equivalent to hash group (N ?1) in version 4.0. For example, hash round 10 in version 3.0 is equivalent to hash group 9 in version 4.0. In other words, the range of hash round from 1 to 100 in version 3.0 has been moved under mapping to the range of hash group number from 0 to 99 in version 4.0. As a simple and fast adjustment, just relocate the hash round 100 in every YinYang element group in version 3.0, to the hash group number 0 in the same YinYang element group in version 4.0, by updating the relevant account for password change.
To promote sale, agent(s), who can realize any sale contract and licensing agreement for the products and services in this business, will be compensated by a minimum commission rate of 2% throughout the validity of the business.
Kok-Wah Lee. (2008, July 25). Methods and systems to
create big memorizable secrets and their applications
in information engineering.
 Kok-Wah Lee. (2008, December
18). Methods and systems to create big memorizable
secrets and their applications in information engineering. PCT Patent
Application [No.: PCT/IB2008/055432], PCT International Publication [No.: WO
2010/010430], WIPO (World Intellectual Property Organization),
 Kok-Wah Lee. (2009, March 14). Memorizable Public-Key Cryptography (MePKC) & Its Applications, First Edition (Version 1.0). Online public listing for archival on 14 March 2009. URL: http://www.archive.org/details/MemorizablePublic-keyCryptographymepkcItsApplications : <Click here> <Errata Sheet>
IP Notice of 2D Key Software:
IP = Intellectual Property
 All rights reserved.
Patent pending in
Novel copyright archived and protected in UN WIPO,
The intellectual properties (IP) in this software application, like patent,
copyright, and trade secret, are protected in
 This is not a sale, but copyright licensing of a software application.
 No web hosting of this software is allowed by an end user in the local area network or Internet.
User Categories under the Software License:
 A first version is a freeware version opened to public for trials, evaluations, and reviews.
 A second version is a shareware version, which is free for certain user types and majority-wise chargeable over the others.
 These software licenses, both for Freeware Edition and Shareware Edition, are free to one or more of the following groups:
(a) User of software "2D Key PW100 4.0 Freeware Edition";
(b) Primary school student;
(c) Secondary school student till pre-university (pre-U) class attached to a secondary school;
(d) Natural person not more than 18 years old;
(e) Public servant of
(f) Public military from
(g) Police officer from China PRC,
(h) Public and private medical service provider from the Earth planet for matters related to medical care done with ownself or a patient; or
(i) Others, if any, as approved by the Author via a written application letter.
 To enjoy the complimentary software licenses, Freeware Edition can be downloaded as it is, but Shareware Edition requires a collection of at least 10 eligible persons and this form has to be sent or email to the software owner.
 To know more about the license, one can download here.
Download the Software:
 2D Key PW5 2.0 Free Edition
5 Slave Keys / 1 Master Key
To be withdrawn from Internet by 31 Dec. 2010
 2D Key PW100 4.0 Freeware Edition
10*10 Slave Keys / 1 Master Key
2 Replacers / 1 Slave Key
 2D Key PW1000 4.0 Shareware Edition
10*100 Slave Keys / 1 Master Key
128 Replacers / 1 Slave Key
for 5 computers / License
Created on 09 July 2008
Updated on 12 September 2009