DepChain — Stage 2

Requirements: Java 21 (Besu EVM / bytecode), Maven 3.6+

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Demos

1. Automatic multi-JVM demo

From the project root:

./run-multijvm-demo.sh

It runs mvn compile, builds a runtime classpath, creates depchain-multijvm.keys if missing, starts four member processes in the background (consensus UDP 30000–30003, client-facing UDP 30100–30103), then runs the batch client in the foreground. That client submits three fixed native DepCoin transfers (Hardhat account 0 → account 1, nonces 0–2) and prints the decided chain indices. Finally it stops the members. Logs: member-0.log … member-3.log.

2. Manual multi-JVM (five terminals)

You must use Maven’s full classpath (Stage 2 depends on web3j, Besu, etc.). Plain java -cp target/classes … alone will fail with NoClassDefFoundError (e.g. org.web3j.crypto.Credentials).

Once — generate keys (writes depchain-multijvm.keys at the repo root):

cd /path/to/DepChain
mvn -version   # must show Java 21.x
mvn -q clean compile
mvn -q exec:java -Dexec.args="genconfig"

Four terminals — one member each:

mvn -q exec:java -Dexec.args="member 0"
mvn -q exec:java -Dexec.args="member 1"
mvn -q exec:java -Dexec.args="member 2"
mvn -q exec:java -Dexec.args="member 3"

Wait until all show Member X running (consensus port …, client port …).

Fifth terminal — choose one:

Mode	Command	Purpose
Batch client	mvn -q exec:java -Dexec.args="client"	Sends the same 3 scripted DepCoin txs as the shell script; binds UDP 30200.
Interactive REPL	mvn -q exec:java -Dexec.args="interactive"	IST / DepCoin commands (see next section); binds UDP 30217 by default.

Interactive REPL (interactive)

Use this after the four members are up.

Startup: waits ~4s, prints the derived IST contract address (from genesis deployer + nonce 0), then accepts input.

Signing identity: genesis includes two Hardhat-style EOAs. Use use 0 or use 1 to sign as that account (new DepChainClient with the matching private key). Only 0 and 1 are valid.

Commands:

Command	Meaning
help	Short built-in help.
use 0 / use 1	Switch active signer (account 0 or 1).
balance dep <addr>	Native DepCoin balance (integer, genesis units).
balance ist <addr>	IST token balance (smallest units + human IST with 2 decimals).
native <to> <whole>	Native DepCoin transfer of whole units from the current signer.
transfer <to> <amount>	IST transfer — amount like 10.0 (2 decimals).
approve <spender> <amount>	IST approve (after mitigations: non-zero → non-zero may require allowance reset; see tests).
transferFrom <from> <to> <amount>	IST transferFrom — current signer must be the approved spender (typical flow: use 1 to act as spender).
quit / exit	Leave the REPL.

Suggested walkthrough (with members running):

Demo accounts: 0 = 0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266, 1 = 0x70997970C51812dc3A010C7d01b50e0d17dc79C8.

1. use 0 → balance dep 0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266 (positive; pays gas) → balance ist 0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266 (large; IST minted to deployer in genesis).
2. transfer 0x70997970C51812dc3A010C7d01b50e0d17dc79C8 10.0 → expect IST transfer -> index N with (N \ge 0).
3. balance ist 0x7099…79C8 → expect 10.00 IST (1000 smallest units).
4. use 0 → approve 0x7099…79C8 5.0 → allowance for account 1 as spender.
5. use 1 → transferFrom 0xf39F…92266 0x7099…79C8 2.0 → spender pulls IST; re-check balance ist on both addresses as needed.

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Tests

Full suite

mvn clean test

Stage 2

These classes focus on invalid/forged client traffic, leader/mempool integration, faulty replicas, and Besu-side IST approve rules:

mvn test -Dtest=ClientProtocolByzantineTest,VerifiedBatchLeaderInjectionTest,ByzantineClientIntegrationTest,ByzantineTest,ReplicaFailingTest,ISTCoinBesuExecutionTest

Individual test classes (examples)

Command	What it exercises
mvn test -Dtest=AuthenticatedPerfectLinkTest	APL: send/receive, reject corrupted messages, deduplication.
mvn test -Dtest=HotStuffIntegrationTest	Consensus: 4 replicas decide; view change after leader timeout.
mvn test -Dtest=ByzantineTest	One replica sends bad votes; others still decide.
mvn test -Dtest=IntrusiveNetworkTest	Injectable message loss / retries / view change.
mvn test -Dtest=ClientIntegrationTest	Client broadcast → leader proposes → decide → client response.
mvn test -Dtest=MultiProcessConfigIntegrationTest	Key file → four members → client append.