# Central-Ledger Services
The central ledger is a series of services that facilitate clearing and settlement of transfers between DFSPs, including the following functions:
- Brokering real-time messaging for funds clearing
- Maintaining net positions for a deferred net settlement
- Propagating scheme-level and off-transfer fees
# 1. Central Ledger Process Design
# 1.1 Architecture overview
# 2. Transfers End-to-End Architecture
# 2.1 Transfers End-to-End Architecture for v1.1
# 2.2 Transfers End-to-End Architecture for v1.0
# 3. Database Design
The tables Grey colored tables are specific to the transfer process. The Blue and Green color tables are used for reference purposes during the Transfer process.
Summary of the tables specific to the transfer process;
transfer- stores data related to the transfer;
transferDuplicateCheck- used to identify duplication during the transfer requests process;
transferError- stores information on transfer errors encountered during the transfer process;
transferErrorDuplicateCheck- used to identify duplication error transfer processes;
transferExtensions- stores information on the transfer extension data;
transferFulfilment- stores data for transfers that have completed the prepare transfer process;
transferFulfilmentDuplicateCheck- used the identify duplicate transfer fulfil requests;
transferParticipant- participant information related to the transfer process;
transferStateChange- use to track state changes of each individual transfer, creating and audit trail for a specific transfer request;
transferTimeout- stores information of transfers that encountered a timeout exception during the process;
ilpPacket- stores the ilp package for the transfer;
The remaining tables in the below ERD are either lookup (blue) or settlement-specific (red) and are included as direct or indirect dependencies to depict the relation between the transfer specific entities and the transfer tables.
The Central Ledger database schema definition Central-Ledger Database Schema Definition.
# 4. API Specification
Refer to Central Ledger API in the API Specifications section.