I'm trying to configure an ATA 188 but I am unsure of which image to use. Currently I have 2 2811's with FXS modules and analog phones attached that I am able to make calls between one router and the other without any problems. But I am unsure of how to setup the ATA and I don't have cisco call manager. This is just a lab setup, so it is not connected to the PSTN. I tried setting up the SIP image and plugging it into an etherswitch on one of the routers, but I don't get a dial-tone. I know this is a basic Voip question, but if someone could assist.
Is the number local to this router? Is there an outgoing dial peer for 555000.? You can turn on "debug voip dialpeer" to see what dial peers are being matched.