# Multipath payments ### Evolution over time - [[Atomic Multi-Path Payments]] came first, [proposed](https://lists.linuxfoundation.org/pipermail/lightning-dev/2018-February/000993.html) by [[Olaoluwa Osuntokun]] on [[2018-02-06]] - [[Multipath payments|Base AMP]] came second, [proposed](https://lists.linuxfoundation.org/pipermail/lightning-dev/2018-November/001577.html) by [[ZmnSCPxj]] on [[2018-11-13]] - "Local AMP" was last ( [[Bitcoin Optech]] mentions it as [possibly too optimistic](https://bitcoinops.org/en/newsletters/2018/11/20/#multi-path-payments)), [proposed](https://lists.linuxfoundation.org/pipermail/lightning-dev/2018-November/001626.html) by [[René Pickhardt]] on [[2018-11-16]] ## [Page](https://bitcoinops.org/en/topics/multipath-payments/) on [[Bitcoin Optech]] **Simplified Multipath Payments (SMPs)**, also called **Base AMP**, are LN payments that are split into two or more parts all sharing the same hash and preimage, and which are sent using a different path for each part. Although proposed after atomic multipath payments ([AMP](https://bitcoinops.org/en/topics/atomic-multipath/)), simplified multipath payments required fewer changes to the LN protocol to implement and preserved the ability for spenders to receive a cryptographic proof of payment, so they were the first to be deployed on the production network. The main downside of simplified multipath payments when using [HTLCs](https://bitcoinops.org/en/topics/htlc/) is that third-parties who see multiple payments all using the same hash can infer that they’re part of a larger true payment. Both AMP and SMP allow splitting higher value HTLCs into multiple lower value HTLCs that are more likely to individually succeed, so a spender with sufficient liquidity can use almost all of their funds at once no matter how many channels those funds are split across.