[Shorewall-users] pppoe and /etc/shorewall/interfaces

[hans <ha...@yo...>]

I am a newbie to linux and shorewall. I am reading the shoreall
quickstart guides. I am a bit confused about the following statement:
----------- quote --------------
The firewall has two network interfaces. Where Internet connectivity
is through a cable or DSL "Modem", the External Interface will be the
ethernet adapter that is connected to that "Modem" (e.g., eth0)
unless you connect via Point-to-Point Protocol over Ethernet (PPPoE)
or Point-to-Point Tunneling Protocol (PPTP) in which case the External
Interface will be a ppp interface (e.g., ppp0). If you connect via a
regular modem, your External Interface will also be ppp0. If you
connect via ISDN, your external interface will be ippp0.

     If your external interface is ppp0 or ippp0  then you will want
to set CLAMPMSS=3Dyes in /etc/shorewall/shorewall.conf.
-------- unquote --------------------------------------

The point I am confused about is this:
If my DSL isp (SBC) uses pppoe for connection, what do I put in
/etc/shorewall/interfaces?
net ppp0 detect or net eth0 detect or both?

hans