Source-linked AI summary
Decentralized Trusted Timestamping using the Crypto Currency Bitcoin
Bela Gipp, Norman Meuschke, André Gernandt
TL;DR
Trusted timestamping must prove that digital information existed and remained unaltered at a particular time, but centralized authorities create a single point of dependence. The paper implements a decentralized alternative that hashes content and records those hashes in the Bitcoin blockchain, enabling anonymous, persistent, tamper-proof timestamps without a central authority.
Problem
Existing timestamping approaches depend on a central authority, whose compromise can invalidate issued timestamps; decentralized alternatives are technically demanding and lack direct participant incentives.
Method
The paper implements decentralized timestamping by hashing digital content and embedding aggregated hashes in Bitcoin transactions and its distributed blockchain.
Results
The implemented service enables users to create and verify anonymous, persistent, tamper-proof timestamps without relying on a centralized timestamping authority.
Takeaways & Limitations
The service provides a non-commercial way for users to establish when digital content existed while keeping the underlying data private in recommended submission workflows.
Takeaways & Limitations
The security assumption is that blockchain manipulation becomes possible if more than 50% of participating nodes cooperate maliciously.
Abstract
from arXiv · showhide
Trusted timestamping is a process for proving that certain information existed at a given point in time. This paper presents a trusted timestamping concept and its implementation in form of a web-based service that uses the decentralized Bitcoin block chain to store anonymous, tamper-proof timestamps for digital content. The service allows users to hash files, such as text, photos or videos, and store the created hashes in the Bitcoin block chain. Users can then retrieve and verify the timestamps that have been committed to the block chain. The non-commercial service enables anyone, e.g., researchers, authors, journalists, students, or artists, to prove that they were in possession of certain information at a given point in time. Common use cases include proving that a contract has been signed, a photo taken, a video recorded, or a task completed prior to a certain date. All procedures maintain complete privacy of the user's data.
1 Introduction
The paper introduces decentralized trusted timestamping through a Bitcoin-based web service designed to preserve data integrity while reducing reliance on centralized authorities. It emphasizes decentralized validation, user simplicity, low operating cost, and privacy-preserving operation.
- The paper presents a decentralized trusted timestamping concept implemented as a web service using crypto currencies to authenticate data integrity.
- Its stated benefits are decentralized cryptographic validation, incentives for participating computing nodes, minimal user setup, and low operating cost.
- The service stores hashes rather than users’ digital content, allowing timestamps to be associated with data without transmitting the underlying data.
- The approach replaces a single ledger with a publicly accessible blockchain redundantly maintained by participating crypto-currency nodes.
- The concept applies to any crypto currency, while OriginStamp implements it using Bitcoin because Bitcoin has the largest market capitalization and most participating computing nodes.
- The security assumption is that blockchain manipulation is possible if more than 50% of participating nodes cooperate maliciously.
2 Trusted Timestamping
Established trusted timestamping relies on a central timestamping authority to sign and validate timestamps. The paper identifies this central dependency as a security and cost weakness motivating decentralized alternatives.
- Traditional timestamping requires a central time stamping authority to issue timestamps and ensure their validity.
- The process hashes the original data, combines the hash with a plaintext timestamp, hashes the combination again, and digitally signs it with the authority’s private key.
- Verification recreates the timestamp-generation process and compares the result with the trusted timestamp decoded using the authority’s public key.
- A compromised central authority can invalidate all timestamps issued with its single private key, while linked or transient key schemes reduce this weakness at greater technical and operational cost.
- Decentralized protocols can increase security through multiple-party validation, but their technical demands and lack of direct participant incentives have limited adoption.
3 Decentralized Trusted Timestamping using Crypto Currencies
The paper proposes embedding data hashes in cryptocurrency transactions so the blockchain provides decentralized trusted timestamps. OriginStamp implements this process through browser, email, and application integrations while transmitting hashes instead of content in its recommended workflows.
- Cryptocurrency blockchains can provide trusted timestamps when digital-data hashes are embedded in recorded transactions.
- OriginStamp accepts files or text through a browser, email, or plugins, with client-side or offline hashing ensuring that only hashes are sent to the server in the recommended workflows.
- The service aggregates submitted hashes and converts the aggregate into a Bitcoin address, reducing operating costs by recording one Bitcoin transaction per 24 hours.
- A transaction permanently embeds the aggregated hash and transaction timestamp in Bitcoin’s distributed blockchain, whose chained blocks are maintained through mining.
- Users can verify confirmed transaction timestamps and encoded data through OriginStamp, the Bitcoin blockchain, or emailed verification information.
4 Conclusion and Future Work
The paper concludes that OriginStamp enables anonymous, persistent, tamper-proof timestamps without a centralized authority. Future work focuses on broader application integration and bulk timestamp creation through its API.
- OriginStamp enables users to create anonymous, persistent, tamper-proof timestamps without relying on a centralized timestamping authority.
- Planned extensions include additional plugins, faster timestamp creation, and wider integration through the service’s bulk-timestamping API.
Citation for this Paper
The paper is titled “Decentralized Trusted Timestamping using the Crypto Currency Bitcoin” and is authored by B. Gipp, N. Meuschke, and A. Gernandt.
- B. Gipp, N. Meuschke, and A. Gernandt authored “Decentralized Trusted Timestamping using the Crypto Currency Bitcoin.”
- The paper appeared in the Proceedings of the iConference 2015 in Newport Beach, California, USA.
- The conference took place from March 24–27, 2015.