The Arbiter process runs on duplex servers to:

• Decide which server is in good condition and more able to be active

• Coordinate data shadowing between servers under the control of Duplication Manager

At the physical and data-link layers, three links may serve as redundant inter-arbiter UDP communication paths: the control network A link, the control network B link (if present), or an Ethernet-based duplication link. Two of these links must be present. The redundant inter-arbiter UDP communication paths perform the following functions:

• Enable arbitration between the active and standby servers

• Provide the necessary status signaling for memory refreshes

All inter-arbiter communication links use triple DES encryption for secure communication and control.