3Com 2928 User Guide - Page 323
Application Environment of Trusted Ports, Configuring a trusted port connected to a DHCP server
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Application Environment of Trusted Ports Configuring a trusted port connected to a DHCP server Figure 3-1 Configure trusted and untrusted ports As shown in Figure 3-1, a DHCP snooping device's port that is connected to an authorized DHCP server should be configured as a trusted port to forward reply messages from the DHCP server, so that the DHCP client can obtain an IP address from the authorized DHCP server. Configuring trusted ports in a cascaded network In a cascaded network involving multiple DHCP snooping devices, the ports connected to other DHCP snooping devices should be configured as trusted ports. To save system resources, you can disable the trusted ports, which are indirectly connected to DHCP clients, from recording clients' IP-to-MAC bindings upon receiving DHCP requests. Figure 3-2 Configure trusted ports in a cascaded network Table 3-1 describes roles of the ports shown in Figure 3-2. 3-2
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