Inbound Liquidity 入站容量

Channel Capacity Diagram

Your Node              Channel Capacity 1 BTC           Peer Node

  Your Balance <-------------------------> Peer Balance

  [=============================]..........
  0.8 BTC                                    0.2 BTC

  Outbound capacity: 0.8 BTC    Inbound capacity: 0.2 BTC

When opening new channel (you fund 1 BTC):

  [===============================================]..
  1.0 BTC                                    0 BTC

  Outbound capacity: ~1 BTC     Inbound capacity: 0
  -> Can send payments          -> Cannot receive payments

Passively Acquiring Inbound Capacity

When other nodes open channel to you:
Peer funds 0.5 BTC to open channel

  ..........................[==================]
  0 BTC                                    0.5 BTC

  Your inbound capacity: 0.5 BTC (can receive)
  Your outbound capacity: 0 BTC (need to receive first)

How to Attract Inbound Channels:
• Run a reliable node (high uptime)
• Set reasonable routing fees
• Connect to network hub nodes
• Announce node in forums/communities
• Provide valuable services (routing, liquidity)

Converting Capacity Through Payments

Initial state:
  [===============================================]..
  1.0 BTC                                    0 BTC

After you send 0.3 BTC payment:
  [================================]..............
  0.7 BTC                                    0.3 BTC

  Outbound capacity: 0.7 BTC     Inbound capacity: 0.3 BTC

Methods:
• Buy goods/services
• Bitrefill gift cards
• Loop Out to on-chain
• Pay to your other channels (circular payment)
• Purchase inbound capacity service

Dual-Funded Channels

Both parties fund when opening channel:
You fund 0.5 BTC + Peer funds 0.5 BTC = 1 BTC channel

  [======================]........................
  0.5 BTC                                    0.5 BTC

  Outbound capacity: 0.5 BTC     Inbound capacity: 0.5 BTC

Advantages: Have bidirectional liquidity from the start
Requires: Both support option_dual_fund

Liquidity Ads:
Nodes can advertise liquidity they're willing to provide and pricing

Ad contents:
• Min/max amount
• Lease duration (in blocks)
• Rate (per sat per block)
• Base fee

CLN Support:
lightning-cli funderupdate ...

Loop Out (Off-chain -> On-chain)

Convert Lightning balance to on-chain Bitcoin while gaining inbound capacity:

Initial state:
  You --(1 BTC)--> Loop Node
  Outbound capacity: 1 BTC

After Loop Out 0.5 BTC:
  You <--(0.5 BTC)-- Loop Node
  + 0.5 BTC on-chain (minus fees)

  Inbound capacity: 0.5 BTC

Service Providers:
• Loop by Lightning Labs
• Boltz Exchange
• Deezy
• Breez (integrated in wallet)

Lightning Service Provider Provides Instant Inbound Capacity

JIT (Just-In-Time) Channels:
1. You receive a payment request
2. LSP intercepts payment
3. LSP instantly opens channel to you
4. Payment completes through new channel
5. LSP deducts channel opening fee from payment

User experience: No pre-setup needed, automatically get inbound capacity

Common LSPs:
• Phoenix (ACINQ)
• Breez
• Blixt
• Zeus (Olympus)
• Mutiny (Mutiny LSP)

Cost Considerations:
• JIT channel fees usually deducted from payment
• Zero-conf channels reduce waiting time
• Suitable for small users; large users save by self-managing

Recommended Strategies for Different Scenarios

Individual Users (primarily receiving):
• Use LSP wallets (Phoenix, Breez)
• Let LSP auto-manage inbound capacity
• Costs deducted from received payments

Small Merchants:
• Purchase inbound capacity from large nodes
• Use Loop Out for periodic conversion
• Consider Lightning Pool rental
• Maintain multiple inbound channels for risk distribution

Routing Nodes:
• Prioritize dual-funded channels
• Use liquidity ads
• Actively balance channels
• Mutually open channels with other routing nodes
• Monitor and optimize inbound/outbound ratio

Large Merchants/Exchanges:
• Professional liquidity management
• Build own liquidity infrastructure
• Establish relationships with multiple large nodes
• Consider running multiple nodes