The Local Server Set
Local servers reside on the same LAN and maintain their clocks by synchronizing with each other. Due to the high throughput on this type of network, the skews between the local servers on a LAN are normally maintained at under 200 milliseconds. If at least one of the servers in the local set synchronizes with an accurate time-provider, inaccuracies at each server may be less.
When a server is first initialized, it exports its binding to its entry in the namespace and adds its name entry to the LAN profile. Every server is automatically entered in the LAN profile for the related portion of the network. Local servers also import bindings from the LAN profile to build lists of servers with which they can synchronize.
Local servers perform time interval computations, adjust their clocks, and provide time values to each other for synchronization purposes. Each server attempts to synchronize with every other server in the local set at periodic intervals. At longer intervals, clerks request time values from the local servers. Clerks, however, need only to request intervals from the number of servers determined by the minservers attribute, which is usually a subset of all the local servers.