As far as I know, in order to get similar functionality from socket.io you'd have to run it in websocket-only mode in order to use proper load-balancing, use an adapter like socket.io-redis for cross-node messaging and channel subscription / broadcasting.

It looks like SocketCkuster does this plus add another layer of managed load-balancing and handshaking, i.e it's designed around being clustered rather than socket.io which seems to be designed for single server.

I'd love to hear if this is correct and see some performance comparisons of SocketCluster vs Socket.io configured similarly (as above).

Does that mean that I could have any node send a socket message to any client now?