Quick Reference Guide

ProSafe VPN Firewall 50 FVS338 Reference Manual
Connecting the VPN Firewall to the Internet 2-17
v1.0, January 2010
3. Edit the default information that you want to change in the following sections of the screen:
• MTU Size. The normal MTU (Maximum Transmit Unit) value for most Ethernet
networks is 1500 Bytes, or 1492 Bytes for PPPoE connections. For some ISPs you may
have to reduce the MTU. But this is rarely required, and should not be done unless you are
sure it is necessary for your ISP connection.
• Speed. In most cases, your VPN firewall can automatically determine the connection
speed of the Internet (WAN) port. If you cannot establish an Internet connection and the
Internet LED blinks continuously, you may have to manually select the port speed.
AutoSense is the default.
If you know that the Ethernet port on your broadband modem supports 100BaseT, select
100BaseT Half_Duplex; otherwise, select 10BaseT Half_Duplex. Use the half-duplex
settings unless you are sure you need full duplex.
• Router's MAC Address. Each computer or router on your network has a unique 32-bit
local Ethernet address. This is also referred to as the computer's MAC (Media Access
Control) address. The default is Use Default Address. However, if your ISP requires
MAC authentication, then select either
– Use this Computer’s MAC address to enable the VPN firewall to use the MAC
address of the computer you are now using, or
– Use This MAC Address to manually type in the MAC address that your ISP expects.
The format for the MAC address is XX:XX:XX:XX:XX:XX (numbers 0-9 and either
uppercase or lowercase letters A-F). If you select Use This MAC Address and then type
in a MAC address, your entry will be overwritten.
4. Click Apply to save your settings.
To configure the dial-up advanced WAN options:
1. Select Network Configuration from the main menu and Dial-up ISP Settings from the
submenu.
2. Click the Advanced link. The Dial-up Advanced Options screens displays.
3. If required, change the standard MTU value for the dial-up modem. This is the only settings
that you can change on this screen. The standard value for the MTU is 576 bytes, but some
ISPs may require that you reduce the MTU. However, this is rarely required, and should not be
done unless specifically required by the ISP.
4. Click Apply to save your settings.