Configuring VoIP [ Cisco Vs Maipu]

In the VoIP (Voice over IP) configuration, there is a conception dial-peer
that is used to distinguish different types of session segments. There are
two kinds of dial-peers:
POTS — A traditional telephone network peer, such as commonly used
telephone interfaces, PSTN telephone line interface (Z interface), etc.
VoIP — IP network peers (passing via the IP network, related with the
remote telephone segment.)
Seeing the two kinds of dial-peers at the caller: