SMC Networks SMC2804WBR V.2 - Manual (Page 51)

Advanced Setup
49
Point-to-Point Over Ethernet (PPPoE)
Enter the PPPoE User Name and Password assigned by your
Service Provider. The Service Name is normally optional, but
may be required by some service providers.
The MTU (Maximum Transmission Unit) governs the maximum
size of the data packets. Leave this on the default value (1454)
unless you have a particular reason to change it.
Enter a Maximum Idle Time (in minutes) to define a maximum
period of time for which the Internet connection is maintained
during inactivity. If the connection is inactive for longer than the
Maximum Idle Time, it will be dropped. (Default: 10 minutes).
Enable the Auto-reconnect option to automatically re-establish
the connection as soon as you attempt to access the Internet again.
Note: Please be aware that the setting of [Maximum Idle
Time] to "0" and/or [Auto-Reconnect] enabled can
cause an increase of your telephone bill if you don't
have signed a flatrate.