I'm pretty new to the IPT part of Cisco. I'm planning on buying a Voip router, but am not sure if what I want is possible. See attachment for the setup I'm planning on building.
The Cisco 881 should register itself by the VOIP provider. One telephone number is online that way. Also there is a PSTN line in the house with a different number.
Outgoing calls from the phone in the house should use the VOIP line, unless that's down, then they should be routed to the PSTN line.
Outgoing calls from the fax should use the PSTN line.
Incomming calls on the PSTN line should be routed to the fax.
Incoming calls on the VOIP line should go to the house phone.
Is this possible (standalone) without any additional software/servers?
Thanks for helping!
It depends on what you want to learn. You probably won't be able to do any transcoding or conferencing on that amount of DSPs.
As well, a 1751-V is going to be limited to 12.4(15)T and previous releases, and won't have access to the newer features in 12.4(20)T or later.
As far as plugging an analog telephone in, plugging a line from your provider in, and registering a few IP phones that should be all you need.
I would plug the cards into the DSP calculator to make sure it can run the 4 FXO/FXS ports you want to put into the router.