The following is a brief report from the Hcash team regarding recent events and miscellaneous news. The document itself is comprised of information on international developments, breakthroughs in research and development from the Monash University and the Hong Kong Polytechnic University Research Labs, and information regarding the UBTC mobile wallet airdrop.

Hcash would like to thank all invested members for their tireless efforts.

International Development:

Andrew, our business development manager and other members of Hcash have been making substantial progress in South Korea. So far Korean language support for the mobile wallet has been launched, new offices and a Korean support team are being established, discussions regarding partnerships and listings have been furthered and fan support is growing stronger by the day.

The development team in the US has been making progress (details of development progress in the last developer update) in community building, refining and coding. This in unison with help from the Hybrid Network is ensuring the gradual transition from the placeholder chain to the Main Chain.

The Team in Australia has been busy with coordinating the efforts of all related teams, particularly in allocating new marketing efforts to the development of post-Main Chain activities, liaising with exchanges to enable a smooth swap from placeholder to Main Chain token, and implementing a strategic direction.

Technical Research and Development:

Monash University Research Laboratory

Current Progress:

After receiving a recent progress report from Monash University, we are happy to say that the lab has developed a lattice-based (post-quantum secure) linkable ring signature scheme, and the resulting Ring Confidential Transaction (RingCT) protocol. This will be the first step in creating and implementing a privacy-preserving protocol for Hcash. By the end of April 2018, the lab will public a primitive version of this, online.

Future Objectives:

In the future, the team aim to develop a post-quantum secure RingCT protocol that can support a large number of public keys (i.e. millions) for mix-in.

Hong Kong Polytechnic Research Laboratory

New Staffing:

The lab recently recruited two new researchers. A Ph.D student Ms Xiao Yang, who has received a Masters of Science with Distinction in Information Security from Royal Holloway, University of London — and a post-doctorate student, Dr. Dongqing Xu, currently a Ph.D. candidate at the School of Mathematics and Statistics at Wuhan University. The pair will join the lab in July of this year.

Current Progress:

Cross-Chain Transactions:

In relation to cross-chain transactions, the lab will develop a decentralised anonymous credentials system. The system will allow users to prove their identity in a privacy-preserving manner. Feedback from the counterparty will also be stored on the Blockchain. The end goal is that users will be able to choose whether to conduct the transaction with an anonymous user based on his ‘reputation’ in the system.

So far the labs manuscript, ‘Decentralized Blacklistable Anonymous Credentials with Reputation’ has been accepted for publication in the 23rd Australasian Conference on Information Security and Privacy (ACISP 2018).

Privacy-Preserving Cryptographic Techniques:

The lab aims to provide full transaction privacy for transactions on the Blockchain, including sender privacy, receiver privacy and transaction amount. Additionally, they have presented a universal accumulator with efficient non-membership. This allows a prover to demonstrate that a value is not inside a set of elements in a short proof. An application of their primitive is a dynamic group signature, which enables a group manager to enrol and revoke users continuously.

A manuscript for this has also been published in the 23rd ACISP, under ‘Lattice-Based Universal Accumulator with Efficient Zero-Knowledge Arguments’.

Future Objectives:

After continually analysing the improved design of their decentralized anonymous payment system, the lab expects it could be much faster than the current system in ZCash. Since improvements in the system mainly came from a smaller circuit design, their result could serve as an immediate step when the underlying zero-knowledge proof system (zk-SNARK) is replaced with a version that is quantum-resistant. They aim to continue focusing on this.

UBTC Airdrop Information:

After dealing with discussions and delays, the team at Hcash is happy to say that UBTC airdrops have begun for mobile wallet users. Users who were part of the snapshot, which takes place at the 1st of each month at 12:00 UTC until January 1st, 2022 are reminded that they can still participate by holding HSR in their wallet during a future snapshot.

Users interested in redeeming UBTC from their mobile wallet will need to enter the Hcash mobile wallet application, select the UB tab and enter their registered HyperPay email address (users will need to download and register a HyperPay account to redeem their tokens).

After users have completed this process, UBTC tokens will be distributed to their nominated HyperPay account within 24 hours.