Netgear GSM7212P GSM5212P/GSM7212P/GSM7212F/GSM7224P User Manual - Page 31

Web Management User Guide Field Neighbor State Last Updated Description The state of the neighboring switch: • reachable(1) - The neighbor is reachable by this switch. • stale(2) - Information about the neighbor is scheduled for deletion. • delay(3) - No information has been received from neighbor during delay period. • probe(4) - Switch is attempting to probe for this neighbor. • unknown(6) - Unknown status. The last sysUpTime that this neighbor has been updated. Time ProSafe® Managed Switches software supports the Simple Network Time Protocol (SNTP). You can also set the system time manually SNTP assures accurate network device clock time synchronization up to the millisecond. Time synchronization is performed by a network SNTP server. ProSafe® Managed Switches software operates only as an SNTP client and cannot provide time services to other systems. Time sources are established by Stratums. Stratums define the accuracy of the reference clock. The higher the stratum (where zero is the highest), the more accurate the clock. The device receives time from stratum 1 and above since it is itself a stratum 2 device. The following is an example of stratums: • Stratum 0: A real-time clock is used as the time source, for example, a GPS system. • Stratum 1: A server that is directly linked to a Stratum 0 time source is used. Stratum 1 time servers provide primary network time standards. • Stratum 2: The time source is distanced from the Stratum 1 server over a network path. For example, a Stratum 2 server receives the time over a network link, via NTP, from a Stratum 1 server. Information received from SNTP servers is evaluated based on the time level and server type. SNTP time definitions are assessed and determined by the following time levels: • T1: Time at which the original request was sent by the client. • T2: Time at which the original request was received by the server. • T3: Time at which the server sent a reply. • T4: Time at which the client received the server's reply. The device can poll Unicast server types for the server time. 31