Using another $ connection:
var connection1 = $.connection('/first');
connection1.start();
var connection2 = $.connection('/second');
connection2.start();
Subscription to several hubs:
var connection1 = $.hubConnection("'http://server1.net/signalr");
var connection2 = $.hubConnection("http://server2.net/signalr");
var Hub1= connection1.createHubProxy('Hub1');
var Hub2= connection2.createHubProxy('Hub2');
connection1.start();
connection2.start();
More details here:
here in the section Define a method on the client (without a generated proxy or when added after calling the start method)