Networking
Configuring the WAN
Cisco ISA500 Series Integrated Security Appliance Administrator Guide
106
4
Configuring the Network Addressing Mode
The security appliance supports five types of network addressing modes.
Specify the network addressing mode for the primary WAN and the secondary
WAN depending on your ISP requirements.
Network
Addressing
Mode
Configurations
DHCPC
DHCP is the default settting. If you use DHCP, the WAN port will
be the DHCP client and get the IP address from your ISP or the
peer router. Choose DHCP for most of Internet service providers
that use the cable modem.
Choose this option if your ISP automatically assigns you a
dynamic IP address, and enter the following information:
•
MTU:
The Maximum Transmission Unit is the size, in
bytes, of the largest packet that can be passed on.
Choose
Auto
to use the default MTU size, or choose
Manual
if you want to specify another size.
•
MTU Value:
If you choose
Manual
, enter the custom MTU
size in bytes.
NOTE
Unless a change is required by your ISP, it is recommended
that the MTU values be left as is.