A server starting a client?

Question

I just got a project in my Computer Science class. We got the assignment to use a Password Decryption solution provided by our teachers, and adapt it to be used across our network in a Master/Slave relationship.

This means that a Master (Server) have to contact "dormant" Slaves (Client(s)). We are kind of confused here, as we want to use multiple slaves to decrypt the encrypted passwords we got, but we can't design a system in which the Server is the one to initiate connection to the clients rather than the clients initiating connection to the server.

We have to send the Slaves a list of Encrypted Passwords and make them send back results by comparing them to an encrypted version of a dictionary.

We discussed treating the Master as a Client and the Slaves as Servers, but this would be a problem since you can't stream to different servers through the same port. You would have to change the ports. If this is the only solution then so be it. Any help?

Answer 1

Sounds kind of like what hackers call a 'botnet'.

Basically, a lightweight daemon process is installed into each 'slave' that awaits an instructional message from the master, who sends commands to its entire list of slaves. Upon receipt of this message, the slave executes some other code installed by the hacker based on the instructions received.

In that sense, it is as if the slaves are 'servers'... the master is a client with many servers.

Why stream? Why not datagram?

Answer 2

in JMS (Java Messaging Service) you will have thing call Topic here you will have message producer and multiple consumers.

I preper to use ActiveMq as messaging broker

You could check this also