Set up trunk groups first. Parameters such as the location are assigned to these trunk groups. All trunks belonging to a trunk group then have common parameters, e.g. a common location.

Then set up individual trunks, specifying the corresponding trunk group to which each individual trunk belongs. If there is not yet a trunk group with the appropriate parameters, then while setting up a trunk you can also set up a further trunk group.

For details of which group parameters you need for which trunk type, please see the chapter on the relevant trunk type.

Once you have set up a trunk group, you can set up the individual trunks. An individual trunk can be e.g. an ISDN line with two B channels, or an SIP connection to a provider.

For details of which parameters you need for which trunk type, please see the chapter on the relevant trunk type.