The Negative UNL is a feature of the XRP Ledger consensus protocol that improves liveness (the network's ability to make forward progress) during a partial outage. Using the Negative UNL, servers adjust their effective UNLs based on which validators are currently online and operational, so that a new ledger version can be declared validated even if several trusted validators are offline. The Negative UNL has no impact on how the network processes transactions or what transactions' outcomes are, except that it improves the network's ability to declare outcomes final during some types of partial outages. The feature was originally introduced with version **1.6.0** but it was only possible to manually enable this. If merged, this commit introduces the amendment associated with the feature so that server operators can vote on whether to enable this feature. For more details, please see https://xrpl.org/negative-unl.html This commit closes #3898.
rippled Source
Some of these directories come from entire outside repositories brought in
using [git-subtree][]. This means that the source files are inserted directly
into the rippled repository. They can be edited and committed just as if they
were normal files.
[git-subtree]: https://github.com/apenwarr/git-subtree
If you create a commit that contains files both from a subtree, and from the
rippled source tree, please use care when designing the commit message, since
it will appear in the subtree's individual repository when the changes are
pushed back to the upstream. Better yet, do not mix files from subtrees and
ripple in the same commit at all.
Source folders:
| Folder | Upstream Repo | Description |
|---|---|---|
beast |
N/A | legacy utility code that was formerly associated with boost::beast |
ed25519-donna |
https://github.com/floodyberry/ed25519-donna | Ed25519 digital signatures |
ripple |
N/A | Core source code for rippled |
secp256k1 |
https://github.com/bitcoin-core/secp256k1 | ECDSA digital signatures using the secp256k1 curve |
test |
N/A | Unit tests for rippled |
The following dependencies are downloaded and built using ExternalProject (or FetchContent, where possible). Refer to CMakeLists.txt file for details about how these sources are built :
| Name | Upstream Repo | Description |
|---|---|---|
lz4 |
https://github.com/lz4/lz4 | LZ4 lossless compression algorithm |
nudb |
https://github.com/vinniefalco/NuDB | Constant-time insert-only key/value database for SSD drives (Less memory usage than RocksDB.) |
snappy |
https://github.com/google/snappy | "Snappy" lossless compression algorithm. |
soci |
https://github.com/SOCI/soci | Abstraction layer for database access. |
sqlite |
https://www.sqlite.org/src | An embedded database engine that writes to simple files. |
rocksdb |
https://github.com/facebook/rocksdb | Fast key/value database. (Supports rotational disks better than NuDB.) |
protobuf |
https://github.com/google/protobuf | Protocol buffer data interchange format. Only downloaded/built if a suitable version is not found by find_package, or if the local_protobuf option is explicitly set |