D-Link xStack DGS-3426P User Manual - Cpu Interface Filtering

xStack DGS-3400 Series Layer 2 Gigabit Ethernet Managed Switch 

CPU Interface Filtering 

Due to a chipset limitation and needed extra switch security, the xStack DGS-3400 Series switch incorporates CPU Interface 

filtering. This added feature increases the running security of the Switch by enabling the user to create a list of access rules for 

packets destined for the Switch’s CPU interface. Employed similarly to the Access Profile feature previously mentioned, CPU 

interface filtering examines Ethernet, IP and Packet Content Mask packet headers destined for the CPU and will either forward 

them or filter them, based on the user’s implementation. As an added feature for the CPU Filtering, the xStack DGS-3400 Series 

switch allows the CPU filtering mechanism to be enabled or disabled globally, permitting the user to create various lists of rules 

without immediately enabling them. 

Creating an access profile for the CPU is divided into two basic parts. The first is to specify which part or parts of a frame the 

Switch will examine, such as the MAC source address or the IP destination address. The second part is entering the criteria the 

Switch will use to determine what to do with the frame. The entire process is described below. 

CPU Interface Filtering State Settings 

In the following window, the user may globally enable or disable the CPU Interface Filtering mechanism by using the pull-down 

menu to change the running state. To access this window, click 

ACL > CPU Interface Filtering > CPU Interface Filtering 

State

. Choose 

Enabled

 to enable CPU packets to be scrutinized by the Switch and 

Disabled

 to disallow this scrutiny. 

Figure 9- 18. CPU Interface Filtering State Settings window 

CPU Interface Filtering Table 

The 

CPU Interface Filtering Table

 displays the CPU Access Profile Table entries created on the Switch. To view the 

configurations for an entry, click the hyperlinked 

Profile ID

 number. To view this window click 

ACL

 > 

CPU Interface Filtering

> 

CPU Interface Filtering Table

. 

Figure 9- 19. CPU Interface Filtering Table 

To add an entry to the 

CPU Interface Filtering Table

, click the 

Add Profile 

button. This will open the 

CPU Interface Filtering 

Configuration

 page, as shown below. To remove all CPU Interface Filtering Table entries, click the 

Clear All

 button. There are 

three 

Access Profile Configuration

 pages; one for 

Ethernet

 (or MAC address-based) profile configuration, one for 

IP

 address-

based profile configuration and one for the 

Packet Content Mask

. You can switch between the three 

Access Profile 

Configuration

 pages by using the 

Type

 drop-down menu. The page shown below is the 

Ethernet CPU Interface Filtering 

Configuration

 page. 

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