The V100 Door / Reader Interface connects two access control card readers via Wiegand or Clock-and-Data interface controlling either one or two doors. The V100 features on-board flash memory, allowing program updates to be downloaded via the network. The V100 connects to the V1000 through a high speed RS-485 network. The V1000, in turn, communicates with the system host via industry standard TCP/IP protocol over 10/100 Mbps Ethernet or the Internet. This architecture minimizes the impact on corporate LANs by using only one TCP/IP address for every 32 interfaces and by handling low-level transactions on the RS-485 network.