[tophat9000]

Question: Because this is for a POS Credit Card system there may be more involved then just rolling to a new isp during an outage..(I do PCI...Payment Card Industry...compliant networks) you going to need to contact you pos vendor to get a handle on the data flows and security in place...Bottom line the point of the connection and your need for a stable link is for your Business POS..so start with your POS vendor first so your solution works with POS system requirements..they probably have address this types of issues in the past and might have a simpler solution for redundancy backup..plus addressing being pci compliant.