18 CHAPTER 1: OVERVIEW AND INSTALLATION OF THE MANAGEMENT MODULEHow the Management Module Can Be UsedThe management module can be fitted into either of the transceivermodule slots in the Dual Speed Hub 500; refer to “Installing theManagement Module” on page 20 for information on how to dothis.When multiple Dual Speed Hub 500 units are connected togetherwith cascade cables, they form a single hub (called a stack). Themanagement module can be fitted into any one of the units andprovides management for the whole stack.Management ResilienceProtection Against Unit FailureThe cascade cables that carry the network and managementcommunication between the units in the stack, have resilience builtinto them which protects the communication channel should a unitfail. You can further this resilience by using Hot Swap Cascade Units,which allow you to remove and replace units in the stack, withoutaffecting the other units in the stack.For more information about Hot Swap Cascade Units, contact yoursupplier.Protection Against Losing ManagementIf the stack splits in two (if one of the cascade cables becomesdisconnected), one half of the stack will lose connection to themanagement module if there is just one management module in thestack. You can protect against this by having multiple managementmodules in the same stack (for example one in the top unit and onein the bottom unit). Then, if the stack does split, both halves can bemanaged because they both have access to a management module.
