1-6NTP implementation mode Configuration on S4200G series switchesMulticast modez Configure the local S4200G Ethernet switch to work inNTP multicast server mode. In this mode, the local switchsends multicast NTP messages through the VLANinterface configured on the switch.z Configure the local S4200G Ethernet switch to work inNTP multicast client mode. In this mode, the local switchreceives multicast NTP messages through the VLANinterface configured on the switch.z When a 3Com S4200G Ethernet switch works in server mode or symmetric passive mode, youneed not to perform related configurations on this switch but do that on the client or thesymmetric-active peer.z The NTP server mode, NTP broadcast mode, or NTP multicast mode takes effect only after thelocal clock of the 3Com S4200G Ethernet switch has been synchronized.z When symmetric peer mode is configured on two Ethernet switches, to synchronize the clock of thetwo switches, make sure at least one switch’s clock has been synchronized.NTP Configuration Task ListComplete the following tasks to configure NTP:Task RemarksConfiguring NTP Implementation Modes RequiredConfiguring Access Control Right OptionalConfiguring NTP Authentication OptionalConfiguring Optional NTP Parameters OptionalDisplaying NTP Configuration OptionalConfiguring NTP Implementation ModesAn S4200G Ethernet switch can work in one of the following NTP modes:z Configuring NTP Server/Client Modez Configuring the NTP Symmetric Peer Modez Configuring NTP Broadcast Modez Configuring NTP Multicast ModeTo protect unused sockets against attacks by malicious users and improve security, 3Com S4200Gseries Ethernet switches provide the following functions:
