Allow non-consecutive nonces

[preston-evans98]

Background

Currently, the module system requires users to use nonces exactly in order. The transaction with nonce 2 must be preceded by a transaction with nonce 1. Following Ethereum, we should accept transactions as long as the nonce is greater than the previous one. For example, if a user sends a tranaction with nonce 2 immediately followed by one with some distant nonce (like 10), we should accept both transactions.

Acceptance Criteria

• Transactions are accepted as long as the nonce is greater than the previous one

[preston-evans98]

On further thought, I think this is an anti-feature. It diverges from the behavior of existing chains and gives proposers a lot of extra powe. For example, if I send three txs with increasing nonces, a malicious proposer can ensure that only the last one can ever be included.

[preston-evans98]

cc @cemozerr, it doesn't look like Ethereum has this feature: https://docs.nethereum.com/en/latest/nethereum-managing-nonces/. Are you fine with dropping it?

[LukaszRozmej]

Ethereum allows nonce-gaps, it kind of has to as with network gossip you can get transactions in any order. There is a lot of extra logic to support it though. Ethereum allows also transaction replacement (same-nonce) as long as fee bump is satisfied (10% for normal transactions)