I am searching for registration and call set-up call flows in a single operator domain of IMS (i.e. when both users are in their home network) but I haven't found any in available standards and articles.
Available documents concentrate on the situation when at least one user is outside his/her home network. In such situation I-CSCF is used for registration and call set-up.
Do you know how registration and call set-up call flows will look like when both users are in their home network? Is I-CSCF going to be used?
Thank you in advance for any help.