| ### Designating Global and Courier Servers If your network has WAN links or is an extended LAN, you may need to use global and courier servers to synchronize the nodes in separate network segments. To synchronize nodes across a network, you assign global roles to some servers and courier roles to selected local servers. (See Introduction to the DCE Distributed Time Service for advice on planning the location of global and local courier servers.) To assign server roles, follow the instructions in the following subtopics. More: Advertising Global Servers Assigning the Courier Role to Servers ####