PPPop creates a Server menu with a list of PPP configurations it finds in the PPP Preferences file maintained by Config PPP (or FreePPP Setup) or the Remote Access Connections file maintained by OT/PPP. Underneath the PPP configurations, PPPop will list your TCP/IP configurations if you have more than one of them. And, if you use OT/PPP and have more than one modem configuration, PPPop will list them too below your TCP/IP configurations.
You can directly select another PPP, TCP/IP or modem configuration from PPPop's Server menu - no need to open another control panel. To avoid conflicts, the Server menu is disabled when a PPP connection is open or when your PPP setup control panel is open.
Typically, you would create a PPP configuration for each dialup number available to you. Several of these would be associated with the TCP/IP configuration of one Internet Service Provider. If you change TCP/IP configurations, you would usually need to change the PPP configuration also. I suggest that you create your configurations with descriptive names to make it easier for you to recognize them.
Note: it is possible to select combinations of PPP and TCP/IP configurations which do not work with each other. One way to avoid this error is to use Profiles to accomplish your switching.
If you use more than one type of PPP software, you can assign each to a different TCP/IP configuration. The TCP/IP control panel allows you to select a specific PPP software for each TCP/IP configuration. For example, I have both OT/PPP and FreePPP installed on my system. To change from one to the other, I just change TCP/IP configurations. PPPop then displays the PPP configurations used by the current PPP software.
There are a few things to look out for, though...
When you switch to a different Internet Service Provider while switching TCP/IP configurations, your Internet applications won't be aware of it. For example, an email program will now need to use a different mail server with a different network address and password. You would normally have to manually change those in your email program each time you switch TCP/IP configurations.
The solution to this problem is Internet Config 2.0. With Internet Config 2.0, you can now change "Sets" quickly. Do this switching with the Internet Config application, the Internet Config control strip module, or automatically with Location Manger. Read the chapter "More than one Account?" for some further discussion.
For many applications, however - such as Eudora - you will actually have to quit and relaunch it to properly use the new "Set".
Important: Back up "PPP Preferences" in your System's Preferences folder. It is possible that PPPop could trash it, since it must open and write to it.
OT/PPP or ARA users should also backup "Remote Access Connections".
Remember Server with Profile
If you choose to have PPPop "Remember Server with Profile", it will automatically switch to the PPP, TCP/IP, and modem configuration you were last using with a Profile. If you do not check "Remember Server with Profile", then the Server menu's items will not be changed when you switch between Profiles.
If you use Location Manager however, it would be best not to use "Remember Server with Profile". Let Location Manager do the account switching for you.