On some Windows NT networks, collecting Security Accounts Manager (SAM) information from the domain’s Primary Domain Controller (PDC) may not be suited to all situations. For example, if the PDC is situated on the other side of a slow link (WAN or LAN), collecting SAM information can be time consuming.In Windows NT environments, you can use a local BDC as the source for data collection to improve the speed of data collection as well as network browsing.