# Transactions
# Transaction Filtering
Clients running a light client may wish to filter for transactions on a separate server, in which case LDK will tell them about transactions to filter for.
LDK's Filter
API reference (opens new window)
More information is available in the Blockchain Data guide.
# Fee Estimation
LDK let's you decide your source for fee estimation. This could be Bitcoin Core's fee estimation through estimatesmartfee
RPC method or third-party fee-estimators (opens new window).
LDK's FeeEstimator
docs (opens new window)
LDK's sample node implementation uses Bitcoin Core's fee estimation API here. (opens new window)
# Transaction Broadcasting
You can broadcast transactions in a few ways, using Bitcoin core or other external API's (opens new window)
LDK's BroadcasterInterface
docs (opens new window)
LDK's sample node implementation uses Bitcoin Core's transaction broadcasting API here. (opens new window)