Flashbots Protect, private bundles, and the public mempool
These terms describe related but different parts of transaction delivery. The right comparison depends on what is submitted, which provider receives it, and the chain-specific workflow.
Understand the route before comparing it
Public mempool submission
A transaction sent through a public mempool may be visible to network participants before it is included. Visibility, propagation, ordering, and fees depend on the chain and network conditions; public submission does not by itself describe a single auction mechanism.
Private transaction submission
A private transaction endpoint sends a transaction to a provider rather than broadcasting it through the public mempool. The provider’s documented sharing, builder, inclusion, and failure policies matter. Private submission does not guarantee inclusion or eliminate every execution risk.
Bundles are a distinct format
On Flashbots Auction, a bundle is an ordered group of signed transactions submitted for consideration by block builders. Bundle behavior and supported options are defined by the provider API; do not treat every private transaction as a bundle.
Where FRB fits
FRB is a non-custodial Windows execution assistant. It keeps signing keys local and provides a simulation-first review workflow with private-bundle workflows on supported routes. It is not a relay, managed routing service, automatic failover system, or guarantee of privacy, inclusion, or profitability.
Review the supported product workflow
Check the current feature description and setup documentation before configuring a route.