Throttling Tx Ingress

docs/tx-ingress-control/dd.md

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+# Intro
+
+For the first release of the network where we permit transactions, we want to retain some ability to moderate the rate of transaction ingress. This is difficult with a decentralised system and no solution can be perfect.
+
+But assuming the majority of nodes respect default implementation and behaviour there is some control that can be achieved.
+
+## Current Architecture
+
+Today, when an RPC node receives a transaction, after successful validation it immediately broadcasts the transaction onto the P2P network. The issue here is that we could end up with a flood of transactions and nodes could be overwhelmed.
+
+The knock on effect here could be nodes can't keep up with verifying ClientIVC proofs and/or transactions could be dropped causing diverging mempools.
+
+## Proposed Changes
+
+The only way to moderate the flow of transactions around the network is to control their ingress at source. Once a tx is being propagated it can't be impeded, to do so would exacerbate the problem of divergent mempools.
+
+So the proposed changes are to track the average rate of transaction delivery at the p2p network, say over the last `N` seconds where `N` is configurable. If this goes beyond a configured threshold, transactions will be rejected at the RPC layer until it reduces.