Secure agent payments that produce evidence
A three layer defence stands in front of all four agent payment protocols, x402, MPP, AP2 and A2A. Every block is not just enforced, it is a Falcon-1024 signed, offline verifiable decision you can hand to an auditor. Self hosted, active by default, and built into the AV-RAILS Payment Rails bundle.
One defended edge for four protocols
The same defence sits in front of every protocol the gateway speaks, so you harden once, not four times.
An x402 request, an MPP per method charge, an AP2 signed mandate and an A2A task payment all pass through the same admission and edge controls, and all produce the same shape of signed decision record.
Three layers, active by default
Perimeter firewall
A fail2ban perimeter driven by runtime signals. Hosts that trip the gateway's own defences are banned at the edge before they reach the application.
Substrate Guard Pro
The input admission gate. Structural bounds and a byte size limit reject oversized and malformed requests before canonicalisation, each a signed ADMIT or REJECT.
Edge Sentinel
The runtime edge. IP, geo and ASN blocking, rate and velocity limits, identity allow and deny, and replay and nonce checks, each a signed edge decision.
On by default
All three ship active in a fresh AV-RAILS install. No separate purchase, no extra deployment step, no configuration required to be protected on day one.
Security that produces evidence
This is the difference. A conventional gateway blocks a request and writes a log line you have to trust. AlgoVoi blocks the request and emits a Falcon-1024 signed, content addressed decision that anyone can verify offline, without calling back to us and without trusting the operator.
- Every admission and edge decision carries its own signed reference, for example
edge_decision_ref: sha256:.... - The reason is categorical and machine readable, for example
BLOCK_IP_CIDR,BLOCK_GEO_COUNTRY,BLOCK_RATE_EXCEEDED. - A decision is recomputable from its disclosed fields, so a reviewer confirms what happened and why from the artefact alone.
- Signatures are post quantum by design, so a decision made today stays verifiable across a long retention horizon.
Security stops being a black box and becomes part of the same offline verifiable evidence estate as your settlement and compliance receipts.
Operator control, one switch
An operator security console in the control panel puts the whole defence under your hand. View banned addresses, and pause or resume each layer independently at runtime with no restart. Every change is audit logged.
Your keys, your funds
Custody stays with you. The gateway signs payouts with the operator's own key, held in your environment or your HSM or KMS, and that key never leaves the box. AlgoVoi never holds your funds and never takes custody. Every payout emits a Falcon-1024 signed, no PII receipt that binds the payment reference and a hashed payee, so a movement of funds is itself verifiable evidence.
Rate limiting and abuse controls
Fraud and abuse are stopped at the edge before they reach the engine. Edge Sentinel applies rate and velocity limits and identity allow and deny, and the perimeter firewall bans hosts that trip those defences. Each action is a signed decision, so an abuse block is auditable after the fact, not just dropped.
Is this a WAF?
It does the job a web application firewall does, and more. A conventional WAF blocks a request and writes a log line you have to trust. AV-RAILS blocks the request and emits a Falcon-1024 signed, offline verifiable decision, so the block is portable evidence rather than an opaque allow or deny. Security you can prove, not just security that happened.
Built into AV-RAILS
You do not bolt this on. It ships inside the AV-RAILS Payment Rails bundle, self hosted and air gap capable, active from the first install. The same two layer suite is also available on its own as the AlgoVoi Security Suite for existing deployments.
Full technical reference: docs.algovoi.co.uk/payment-rails-sqlite