BFT-Banking

Bisantine Fault Tolerant System for Banking

Demo

In this Demo we will exemplify the different functionalities of the developed project.

###Key Generation: We will now create a couple of keys for our client to use and for the accounts:

cd client

First Client:

./keystore.sh (When asked insert your alias and password)

alias: client_1 clientID: 1 password = password

First Account (for client 1): ./keystore.sh (When asked insert your alias and password)

alias: acc_1 clientID: 1 password: password

Second Account (for client 1): ./keystore.sh (When asked insert your alias and password)

alias: acc_2 clientID: 1 password: password

Server keys:

Go to the Home directory ( cd .. )

And create 3 server keys

cd server

./keystore

alias: server1 password: password

./keystore

alias: server2 password: password

./keystore

alias: server3 password: password

Next Steps:

Execute the following commands in the project Home Directory:

cd server-contract

mvn clean install

cd ..

mvn clean compile

mvn clean install

Initializing Server

We will now initialize the necessary servers (on different terminals):

• starting on localhost port 8080 (make sure this address is not already in use);
• the name of the keystore
• the integer representing the number of servers in this case 3

mvn clean compile exec:java -Dexec.args="localhost 8080 server1.p12 3"

mvn clean compile exec:java -Dexec.args="localhost 8081 server2.p12 3"

mvn clean compile exec:java -Dexec.args="localhost 8082 server3.p12 3"

As we can start more than one server, after the initialization, we must press the enter key to proceed with the broadcast of public keys across servers.

After all servers are up and running press "enter" on each server

Initializing Client1

We will now initialize Client 1 .

Open a new terminal.

Change to the Home Directory ( cd .. )

Change to the Client Directory ( cd client )

Run the following command to start a client:

mvn clean compile exec:java -Dexec.args="localhost 8080 1"

The integer that follows the port represents the maximum number of servers that can be down at any given time. In this case since we have 3 server's running we can only tolerate 1 server to be down in other to guarantee the security properties of our system.

When asked insert "1 password" ( corresponds to clientId=1 and password=password)

Creating Client1's accounts

IMPORTANT! DENIAL OF SERVICE - In order to prevent DDOS attack we implemented a POW system in our servers. As such after each operation in the client, the user will be prompted a simple question (random everytime) to solve. Make sure to type the anwser to this question whenever prompted and press enter.

IMPORTANT! Fault tolerance - In order to test how our system works with servers we suggesting utilizing signals such as SIGTSTP (ctrl+z) to stop the servers and the command fg to resume the servers.

Run the commands to create 2 accounts:

1 acc_1 password

1 acc_2 password

Some examples / tests / operations:

• Lets check the balance of account 1 by running:

3 acc_1 password 

//The value should be 50.

• Lets audit account 2 by running:

5 acc_2 password
    
//There should be no transactions yet

• Lets transfer 25 units from acc_1 to acc_2:

2 acc_1 acc_2 25 password

//Money should be awaiting confirmation from acc_2

• Lets accept the incoming transfer:

4 acc_2 password

//Money should have entered our account

• Lets check the balance of both accounts and audit them:

//(account 1)
3 acc_1 password
5 acc_1 password 

//there should be 25 units
//there should be 1 transaction)


//(account 2)
3 acc_2 password
5 acc_2 password 

//there should be 75 units 
//there should be 1 transaction

• Lets try sending too much money from acc_1 to acc_2:

2 acc_1 acc_2 1000 password

//there should be an error message

• Lets try to stop the server abruptly and restart it to check if it keeps the same state:

(Control-C on Server) Send the interrupt (terminate) signal SIGINT
    
// Restart both the client and the server as done previously

// Do the following commands on the client

2 acc_1 password

// balance should still be 25

• Shutdown the Client gracefully:

6

• If you wish to reset the state of the servers delete the following file:

PROJECT_HOME_DIR/server/server1.txt PROJECT_HOME_DIR/server/server2.txt PROJECT_HOME_DIR/server/server3.txt