Operation Manual – NTPH3C S3610&S5510 Series Ethernet Switches Chapter 1 NTP Configuration1-151.6 Configuring NTP AuthenticationThe NTP authentication feature should be enabled for a system running NTP in anetwork where there is a high security demand. This feature enhances the networksecurity by means of client-server key authentication, which prohibits a client fromsynchronizing with a device that has failed authentication.1.6.1 Configuration PrerequisitesThe configuration NTP authentication involves configuration tasks to be implementedon the client and on the server.When configuring the NTP authentication feature, pay attention to the followingprinciples:z For all synchronization modes, when you enable the NTP authentication feature,you should configure an authentication key and specify it as a trusted key. Namely,the ntp-service authentication enable command must work together with thentp-service authentication-keyid command and the ntp-service reliableauthentication-keyid command. Otherwise, the NTP authentication functioncannot be normally enabled.z For the server/client mode or symmetric mode, you need to associate thespecified authentication key on the client (symmetric-active peer if in thesymmetric peer mode) with the corresponding NTP server (symmetric-passivepeer if in the symmetric peer mode). Otherwise, the NTP authentication featurecannot be normally enabled.z For the broadcast server mode or multicast server mode, you need to associatethe specified authentication key on the broadcast server or multicast server withthe corresponding NTP server. Otherwise, the NTP authentication feature cannotbe normally enabled.z For the server/client mode, if the NTP authentication feature has not been enabledfor the client, the client can synchronize with the server regardless the NTPauthentication feature has been enabled for the server or not.z For all synchronization modes, the server side and the client side must beconsistently configured.z If the NTP authentication is enabled on a client, the client can be synchronizedonly to a server that can provide a trusted authentication key.1.6.2 Configuration ProcedureI. Configuring NTP authentication for a clientFollow these steps to configure NTP authentication for a client:
