The value of the object tmnxLudbHostPppL2tpSvcId specifies the
service ID of the service from where to take the tunnel group
(tmnxLudbHostPppL2tpTunnelGroup) to use to setup an L2TP LAC
tunnel/session.
If the value of this object is 0, L2TP tunneling will be done from
the base router context.