Advanced Settings; Ip Level Settings - D-Link DFL-1660 User Manual

Chapter 13. Advanced Settings
This chapter describes the additional configurable advanced settings for NetDefendOS that are not
already described in the manual. In the Web Interface these settings are found under System >

Advanced Settings.

The settings are divided up into the following categories:
• IP Level Settings, page 552
• TCP Level Settings, page 556
• ICMP Level Settings, page 561
• State Settings, page 562
• Connection Timeout Settings, page 564
• Length Limit Settings, page 566
• Fragmentation Settings, page 568
• Local Fragment Reassembly Settings, page 572
• Miscellaneous Settings, page 573

13.1. IP Level Settings

Log Checksum Errors
Logs occurrences of IP packets containing erroneous checksums. Normally, this is the result of the
packet being damaged during network transport. All network units, both routers and workstations,
drop IP packets that contain checksum errors. However, it is highly unlikely for an attack to be
based on illegal checksums.
Default: Enabled
Log non IPv4/IPv6
Logs occurrences of IP packets that are not IPv4 or IPv6.
Default: Enabled
Log Received TTL 0
Logs occurrences of IP packets received with the "Time To Live" (TTL) value set to zero. Under no
circumstances should any network unit send packets with a TTL of 0.
Default: Enabled
Note: Activating setting changes
After any advanced setting is changed, the new NetDefendOS configuration must be
activated in order for the new value to take effect.
552