Cryptocurrency wallet
A cryptocurrency wallet is a device,[1] physical medium,[2] program or a service which stores the public and/or private keys[3] for cryptocurrency transactions. In addition to this basic function of storing the keys, a cryptocurrency wallet more often also offers the functionality of encrypting and/or signing information. Signing can for example result in executing a smart contract, a cryptocurrency transaction (see "bitcoin transaction" image), identification or legally signing a 'document' (see "application form" image).[4]
Technology
Private and public key generation
A crypto currency wallet works by a theoretical or random number being generated and used with a length that depends on the algorithm size of the cryptocurrency's technology requirements. The number is then converted to a private key using the specific requirements of the cryptocurrency cryptography algorithm requirement. A public key is then generated from the private key using whichever cryptographic algorithm requirements are required. The private key is utilised by the owner to access and send cryptocurrency and is private to the owner, whereas the public key is to be shared to any third party to receive cryptocurrency.
Up to this stage no computer or electronic device is required and all key pairs can be mathematically derived and written down by hand. The private key and public key pair (known as an address) are not known by the blockchain or anyone else. The blockchain will only record the transaction of the public address when cryptocurrency is sent to it, thus recording in the blockchain ledger the transaction of the public address.
Duplicate private keys
Collision (two or more wallets having the same private key) is theoretically possible, since keys can be generated without being used for transactions, and are therefore offline until recorded in the blockchain ledger. However, this possibility is negated because the theoretical probability of two or more private keys being the same is extremely low. The number of possible wallets in any cryptocurrency cryptography is slightly less number of than atoms in the universe[citation needed], a number so high that duplicating or hacking a certain key would be inconceivable.[5] [6]
Seed phrases
In modern convention a seed phrase is now utilised which is a 12 to 24 word and greater word phrase that is an unencrypted form of the private key in dictionary word format which is simpler to remember then a encrypted cryptographic key in another string format. When online, exchange and hardware wallets are generated using random numbers a seed phrase is asked to be recorded by the user, so that when access to the wallet becomes misplaced, damaged or compromised, the seed phrase can be used to re-access the wallet and associated keys and cryptocurrency.[7]
Wallets
A number of technologies known as wallets exist that store the key value pair of private and public key known as wallets. A wallet hosts the details of the key pair making transacting cryptocurrency possible. Multiple methods exist for storing keys or seeds in a wallet. [8]
Crypto wallets vis-à-vis dapp browsers
Dapp browsers are specialized software that sustains new generation decentralized applications. Dapp browsers are considered to be the browsers of Web3 and are the gateway to access the decentralized applications which are working based on blockchain technology. That means all dapp browsers must have a unique code system to unify all the different codes of the dapps.
While crypto wallets are focused on the exchange, purchase, sale of digital assets[9] and support narrowly targeted applications, the browsers support different kinds of applications of various formats, including exchange, games, NFTs marketplaces, etc.[10]
Technical specifications of different browsers may or may not include features such as:
- Full support for all modern Web2.0 technologies;
- Built-in Ethereum mainnet/testnet RPC, fully compatible with Web3.0;
- Built-in Ethereum wallet (using smart contracts);
- Dapp naming support
Characteristics
In addition to the basic function of storing the keys, a cryptocurrency wallet may also have one or more of the following characteristics.
Simple cryptocurrency wallet
A simple cryptocurrency wallet contains pairs of public and private cryptographic keys. The keys can be used to track ownership, receive or spend cryptocurrencies.[11] A public key allows others to make payments to the address derived from it, whereas a private key enables the spending of cryptocurrency from that address.[12]
The cryptocurrency itself is not in the wallet. In the case of bitcoin and cryptocurrencies derived from it, the cryptocurrency is decentrally stored and maintained in a publicly available distributed ledger called the blockchain.[11]
eID wallet
Some wallets are specifically designed to be compatible with a framework. The European Union is creating an eIDAS compatible European Self-Sovereign Identity Framework (ESSIF) which runs on the European Blockchain Services Infrastructure (EBSI). The EBSI wallet is designed to (securely) provide information, an eID and to sign 'transactions'.[4]
Multisignature wallet
In contrast to simple cryptocurrency wallets requiring just one party to sign a transaction, multisignature wallets require multiple parties to sign a transaction.[13] Multisignature wallets are designed for increased security.[14]
Smart contract
In the cryptocurrency space, smart contracts are digitally signed in the same way a cryptocurrency transaction is signed. The signing keys are held in a cryptocurrency wallet.
Key derivation
Sequential deterministic wallet
A sequential deterministic wallet utilizes a simple method of generating addresses from a known starting string or "seed". This would utilize a cryptographic hash function, e.g. SHA-256 (seed + n), where n is an ASCII-coded number that starts from 1 and increments as additional keys are needed.[citation needed]
Armory deterministic wallet
Bitcoin Armory, an open source, Python-based, wallet-management application for the Bitcoin network, utilized its own implementation the hierarchical deterministic scheme and served as inspiration for the BIP32 standard.[15]
Non-deterministic wallet
In a non-deterministic wallet, each key is randomly generated on its own accord, and they are not seeded from a common key. Therefore, any backups of the wallet must store each and every single private key used as an address, as well as a buffer of 100 or so future keys that may have already been given out as addresses but not received payments yet.[16][11]: 94
Concerns
Wallet access permissions
When choosing a wallet, the owner must keep in mind who is supposed to have access to (a copy of) the private keys and thus potentially has signing capabilities. In case of cryptocurrency the user needs to trust the provider to keep the cryptocurrency safe, just like with a bank. Trust was misplaced in the case of the Mt. Gox exchange, which 'lost' most of their clients' bitcoins. Downloading a cryptocurrency wallet from a wallet provider to a computer or phone does not automatically mean that the owner is the only one who has a copy of the private keys. For example, with Coinbase, it is possible to install a wallet on a phone and to also have access to the same wallet through their website.
Vulnerabilities
A wallet can also have known or unknown vulnerabilities. A supply chain attack or side-channel attack are ways of a vulnerability introduction. In extreme cases even a computer which is not connected to any network can be hacked.[17]
When using a software wallet for receiving cryptocurrency, access to the receiving wallet is not needed—the sending party only need know the destination address, thus anyone can send cryptocurrency to an address. Only the one who has the private key of the corresponding (public key) address otherwise has access.
See also
References
- ^ Roberts, Daniel (15 December 2017). "How to send bitcoin to a hardware wallet (url=https://finance.yahoo.com/news/send-bitcoin-hardware-wallet-140141385.html". Yahoo! Finance.
- ^ Divine, John (1 February 2019). "What's the Best Bitcoin Wallet?". U.S. News & World Report. Retrieved 12 March 2019.
- ^ Newman, Lily Hay (2017-11-05). "How to Keep Your Bitcoin Safe and Secure". Wired. ISSN 1059-1028. Retrieved 2019-03-10.
- ^ a b "European Blockchain Services Infrastructure (EBSI)". European Commission. Retrieved 24 July 2020.
- ^ Yadav, Nagendra Singh & Goar, Vishal & Kuri, Manoj. (2020). Crypto Wallet: A Perfect Combination with Blockchain and Security Solution for Banking. International Journal of Psychosocial Rehabilitation. 24. 6056-6066. 10.37200/IJPR/V24I2/PR2021078.
- ^ Guler, Sevil (2015). "Secure Bitcoin Wallet" (PDF). UNIVERSITY OF TARTU FACULTY OF MATHEMATICS AND COMPUTER SCIENCE Institute of Computer Science Computer Science Curriculum: 48 – via core.ac.uk.
- ^ Shaik, Cheman. (2020). Securing Cryptocurrency Wallet Seed Phrase Digitally with Blind Key Encryption. International Journal on Cryptography and Information Security. 10. 1-10. 10.5121/ijcis.2020.10401.
- ^ Jokić, Stevo & Cvetković, Aleksandar Sandro & Adamović, Saša & Ristić, Nenad & Spalević, Petar. (2019). Comparative analysis of cryptocurrency wallets vs traditional wallets. Ekonomika. 65. 10.5937/ekonomika1903065J.
- ^ Frankenfield, Jake (2021-08-16). "Blockchain Wallet".
{{cite web}}
: CS1 maint: url-status (link) - ^ Deepanshu, Bhatt (2019). "Best DApp Browsers to use in 2019".
{{cite web}}
: CS1 maint: url-status (link) - ^ a b c Antonopoulos, Andreas (12 July 2017). Mastering Bitcoin: Programming the Open Blockchain. O'Reilly Media, Inc. ISBN 9781491954386. Retrieved 14 September 2017.
- ^ "Bitcoin Wallets: What You Need to Know About the Hardware". The Daily Dot. 2018-11-20. Retrieved 2019-03-10.
- ^ "Bitcoin Startup Predicts Cryptocurrency Market Will Grow By $100 Billion in 2018". Fortune. Retrieved 2019-02-15.
- ^ Graham, Luke (2017-07-20). "$32 million worth of digital currency ether stolen by hackers". www.cnbc.com. Retrieved 2019-02-15.
- ^ Wuille, Pieter (11 February 2012). "BIP-0032: Hierarchical Deterministic Wallets". GitHub. Retrieved 17 October 2021.
- ^ Acharya, Vivek (30 June 2021). "How Ethereum Non-Deterministic and Deterministic Wallets Work". Oracle Corporation. Retrieved 17 October 2021.
- ^ Air-gap jumpers on cyber.bgu.ac.il