This shared secret may be directly used as a key, or to derive another key.
The key, or the derived key, can then be used to encrypt subsequent communications using a symmetric-key cipher.
An example of the derived key would be the shared secret between the ephemeral session key of a sender of an onion with the node's public key of a hop of the onion as described and used by the SPHINX Mix Format.
Via https://en.wikipedia.org/w/index.php?title=Elliptic-curve_Diffie%E2%80%93Hellman&oldid=836070673
digital signature::
A digital signature is a mathematical scheme for verifying the authenticity and integrity of digital messages or documents.
They can be seen as cryptographic commitments in which the message is not hidden.
A cryptographic hash function is a mathematical algorithm that maps data of arbitrary size to a bit string of a fixed size (a hash) and is designed to be a one-way function, that is, a function which is infeasible to invert.
The only way to recreate the input data from an ideal cryptographic hash function's output is to attempt a brute-force search of possible inputs to see if they produce a match.
From Wikipedia: https://en.wikipedia.org/w/index.php?title=Cryptographic_hash_function&oldid=868055371
hashlocks::
A hashlock is a Bitcoin Script spending condition that restricts the spending of an output until a specified piece of data is revealed. Hashlocks have the useful property that once any hashlock is revealed through spending, any other hashlock secured using the same key can also be spent. This makes it possible to create multiple outputs that are all encumbered by the same hashlock and which all become spendable at the same time.
@ -274,7 +271,6 @@ onion routing::
The encrypted data is transmitted through a series of network nodes called onion routers, each of which peels away a single layer, uncovering the data's next destination.
When the final layer is decrypted, the message arrives at its destination.
The sender remains anonymous because each intermediary knows only the location of the immediately preceding and following nodes.
From Wikipedia: https://en.wikipedia.org/w/index.php?title=Onion_routing&oldid=870849217
output::
The output of a Bitcoin transaction, also called an Unspent Transaction Output or UTXO.
@ -425,10 +421,9 @@ soft fork::
Soft fork, or soft-forking change, is a protocol upgrade that's forward- and backward-compatible so it allows both old nodes and new nodes to continue using the same chain.
SPHINX Mix Format::
A particular technique for Onion Routing used in the Lightning Network and invented by George Danezis and Ian Goldberg in 2009.
A particular technique for Onion Routing used in the Lightning Network and invented by https://cypherpunks.ca/~iang/pubs/Sphinx_Oakland09.pdf[George Danezis and Ian Goldberg in 2009].
With the SPHINX Mix Format, each message of the onion package is padded with some random data so that no single hop can estimate how far along the route it has traveled.
While the privacy of the sender and receiver of the payment is protected, each node is still able to return an error message along the path to the originator of the message.
The paper can be found at https://cypherpunks.ca/~iang/pubs/Sphinx_Oakland09.pdf[].
submarine swap::
A submarine swap is a trustless atomic swap between on-chain Bitcoin addresses and off-chain Lightning Network payments. Just as LN payments use HTLCs that make the final claim on funds conditional on the recipient revealing a secret (hash preimage), submarine swaps use the same mechanism to transfer funds across the on-chain/off-chain barrier with minimal trust. Reverse submarine swaps allow swaps in the opposite direction, from an off-chain LN payment to an on-chain Bitcoin address.
@ -460,7 +455,6 @@ wallet::
watchtower::
Watchtowers are a security service on the Lightning network that monitors payment channels for potential protocol breaches.
In the case that one of the channel partners goes offline or loses their backup, a watchtower keeps their own backups and can restore their channel information.
They also monitor the Bitcoin blockchain and can submit a penalty transaction in the case that one of the partners tries to "cheat" by broadcasting an outdated state.
+
Watchtowers can be run by the channel partners themselves, or as a paid service offered by a third party. Watchtowers have no control over the funds in the channels themselves.
They also monitor the Bitcoin blockchain and can submit a penalty transaction in the case that one of the partners tries to "cheat" by broadcasting an outdated state. Watchtowers can be run by the channel partners themselves, or as a paid service offered by a third party. Watchtowers have no control over the funds in the channels themselves.
Some contributed definitions have been sourced under a CC-BY license from the https://en.bitcoin.it/wiki/Main_Page[Bitcoin Wiki], https://en.wikipedia.org[Wikipedia], https://github.com/bitcoinbook/bitconbook[Mastering Bitcoin] or from other open source publications.
Andreas M. Antonopoulos
3 years ago