f494433cbf
In this commit, we introduce a new method to the channel router's config struct: QueryBandwidth. This method allows the channel router to query for the up-to-date available bandwidth of a particular link. In the case that this link emanates from/to us, then we can query the switch to see if the link is active (if not bandwidth is zero), and return the current best estimate for the available bandwidth of the link. If the link, isn't one of ours, then we can thread through the total maximal capacity of the link. In order to implement this, the missionControl struct will now query the switch upon creation to obtain a fresh bandwidth snapshot. We take care to do this in a distinct db transaction in order to now introduced a circular waiting condition between the mutexes in bolt, and the channel state machine. The aim of this change is to reduce the number of unnecessary failures during HTLC payment routing as we'll now skip any links that are inactive, or just don't have enough bandwidth for the payment. Nodes that have several hundred channels (all of which in various states of activity and available bandwidth) should see a nice gain from this w.r.t payment latency.
Lightning Network Daemon
The Lightning Network Daemon (lnd) - is a complete implementation of a
Lightning Network node and currently deployed on
testnet3 - the Bitcoin Test Network. lnd has several pluggable back-end
chain services including btcd (a
full-node), bitcoind, and
neutrino (a new experimental light client). The project's codebase uses the
btcsuite set of Bitcoin libraries, and also
exports a large set of isolated re-usable Lightning Network related libraries
within it. In the current state lnd is capable of:
- Creating channels.
- Closing channels.
- Completely managing all channel states (including the exceptional ones!).
- Maintaining a fully authenticated+validated channel graph.
- Performing path finding within the network, passively forwarding incoming payments.
- Sending outgoing onion-encrypted payments through the network.
- Updating advertised fee schedules.
- Automatic channel management (
autopilot).
Lightning Network Specification Compliance
lnd fully conforms to the Lightning Network specification
(BOLTs). BOLT stands for:
Basic of Lightning Technologies. The specifications are currently being drafted
by several groups of implementers based around the world including the
developers of lnd. The set of specification documents as well as our
implementation of the specification are still a work-in-progress. With that
said, the current status of lnd's BOLT compliance is:
- BOLT 1: Base Protocol
- BOLT 2: Peer Protocol for Channel Management
- BOLT 3: Bitcoin Transaction and Script Formats
- BOLT 4: Onion Routing Protocol
- BOLT 5: Recommendations for On-chain Transaction Handling
- BOLT 7: P2P Node and Channel Discovery
- BOLT 8: Encrypted and Authenticated Transport
- BOLT 9: Assigned Feature Flags
- BOLT 10: DNS Bootstrap and Assisted Node Location
- BOLT 11: Invoice Protocol for Lightning Payments
Developer Resources
The daemon has been designed to be as developer friendly as possible in order
to facilitate application development on top of lnd. Two primary RPC
interfaces are exported: an HTTP REST API, and a gRPC
service. The exported API's are not yet stable, so be warned: they may change
drastically in the near future.
An automatically generated set of documentation for the RPC APIs can be found at api.lightning.community. A set of developer resources including talks, articles, and example applications can be found at: dev.lightning.community.
Finally, we also have an active
Slack where protocol developers, application developers, testers and users gather to
discuss various aspects of lnd and also Lightning in general.
Installation
In order to build from source, please see the installation instructions.
IRC
- irc.freenode.net
- channel #lnd
- webchat