It depends on the kind of switch you’re using and the nodes that you are connecting to. For example, if you are using a softswitch you have an option of using M2UA, M3UA or simply TDM based ss7. If you are also connecting to some nodes that also use sigtran then you can also use the above signalling protocols as well to connect to those. In the event that you have an IN system (or a RTBS) then you might need CAMEL as well.
I hope that gives you a rough idea of what to check for.