How Is a non voip phone call routed to a gateway unit ?

[Reprovoid]

Hi.

  I understand how a voip phone can call a non voip phone but I don't understand how It knows to reach a specific gateway unit to convert to analog.

   How does It find the route to the gateway ?

[paolo bevilacqua · Accepted solution]

Because the call signalling  protocol (sccp, sip or whatelse) conveys this information.

[Reprovoid]

Thank you , I'll read up on sip and sscp!