Dhcp Server Screening Settings; Dhcp Screening Port Settings - D-Link DES-3528 User Manual

xStack DES-3528 Series Layer 2 Stackable Fast Ethernet Managed Switch User Manual
Figure 9- 10. Port Security FDB Entries window

DHCP Server Screening Settings

This function allows the user to not only restrict all DHCP Server packets but also to receive any specified DHCP
server packet by any specified DHCP client, it is useful when one or more DHCP servers are present on the network
and both provide DHCP services to different distinct groups of clients. The first time the DHCP filter is enabled it will
create both an access profile entry and an access rule per port entry, it will also create other access rules. These
rules are used to block all DHCP server packets. In addition to a permit DHCP entry it will also create one access
profile and one access rule entry the first time the DHCP client MAC address is used as the client MAC address. The
Source IP address is the same as the DHCP server's IP address (UDP port number 67). These rules are used to
permit the DHCP server packets with specific fileds, which the user has configured.
When DHCP Server filter function is enabled all DHCP Server packets will be filtered from a specific port.

DHCP Screening Port Settings

The following window will allow users to enable ports on the switch to be used in DHCP Server Screening. To view
this window, click Security > DHCP Server Screening > DHCP Screening Port Settings:
Figure 9- 11. DHCP Screening Port Settings window
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