NETGEAR ProSAFE SRX5308 Reference Manual page 73

ProSAFE Gigabit Quad WAN SSL VPN Firewall SRX5308
Figure 46.
4. Enter the settings as described in the following table:
Table 13. WAN Advanced Options screen settings
Setting
MTU Size
Make one of the following selections:
Default
Custom
Description
Select the Default radio button for the normal maximum transmit unit (MTU)
value. For most Ethernet networks, this value is 1500 bytes, or 1492 bytes for
PPPoE connections.
Select the Custom radio button, and enter an MTU value in the Bytes field. For
some ISPs, you might need to reduce the MTU. This is rarely required, and
should not be done unless you are sure that it is necessary for your ISP
connection.
IPv4 and IPv6 Internet and WAN Settings
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