No relevant resource is found in the selected language.

This site uses cookies. By continuing to browse the site you are agreeing to our use of cookies. Read our privacy policy>Search


To have a better experience, please upgrade your IE browser.


Configuration Guide - Security

S7700 and S9700 V200R011C10

This document describes the configurations of Security, including ACL, reflective ACL, local attack defense, MFF, attack defense, traffic suppression and storm control, ARP security, port security, DHCP snooping, ND snooping, PPPoE+, IPSG, SAVI, URPF, keychain, separating the management plane from the service plane, security risks.
Rate and give feedback:
Huawei uses machine translation combined with human proofreading to translate this document to different languages in order to help you better understand the content of this document. Note: Even the most advanced machine translation cannot match the quality of professional translators. Huawei shall not bear any responsibility for translation accuracy and it is recommended that you refer to the English document (a link for which has been provided).
Defense Against Bogus DHCP Server Attacks

Defense Against Bogus DHCP Server Attacks


Because DHCP servers and DHCP clients lack authentication mechanisms between them, each DHCP server newly configured on a network assigns IP addresses and other network parameters to DHCP clients. If the assigned IP addresses and other network parameters are incorrect, errors may occur on the network.

In Figure 9-4, authorized and unauthorized DHCP servers can receive DHCP Discover messages broadcast by DHCP clients.

Figure 9-4  DHCP client sending DHCP Discover messages

If a bogus DHCP server sends a bogus DHCP Reply message with an incorrect gateway address, Domain Name System (DNS) server address, or IP address to a DHCP client, as shown in Figure 9-5, the DHCP client cannot obtain the correct IP address and required information. The authorized user then fails to access the network and user information security is compromised.

Figure 9-5  Bogus DHCP server attack


To prevent attacks from a bogus DHCP server, configure the trusted interface and untrusted interfaces on the device.

You can configure the interface directly or indirectly connected to the authorized DHCP server as the trusted interface and other interfaces as untrusted interfaces. The device then discards DHCP Reply messages received on untrusted interfaces, preventing bogus DHCP server attacks, as shown in Figure 9-6.

Figure 9-6  Trusted interface and untrusted interfaces
Updated: 2019-04-01

Document ID: EDOC1000178319

Views: 146194

Downloads: 79

Average rating:
This Document Applies to these Products
Related Documents
Related Version
Previous Next