We have a customer with some grandfather'd pots line as Analog Trunks in their MCD 4.1 SP2 CXI controller. The quality on these lines are lousy because of their age and the sensitivity of the digital. I was thinking that using SIP trunking we can set up a test trunk to my home office to show the difference in quality using a PRI vs Analog trunks. So is it possible at some scale to use the public internet to support sip trunking?