Avaya 4500 Series Installation Manual page 60

Installing the Avaya Ethernet Routing Switch
to number in this manner throughout the stack. In this configuration, the base unit discovers
the stack in a cascade down (stack down) direction. The following illustration demonstrates a
typical cascade down (stack down) configuration.
Figure 20: Cascade Down (Stack Down) configuration
1. Base Unit
2. Last Unit
3. Cascade Cable
4. Cascade Cable
Important:
Because many network management software packages assume a cascade down (stack
down) configuration, Avaya recommends that you use a cascade down configuration.
Cascade up
In a cascade up (stack up) configuration, the base unit is physically the top unit in the stack.
The cable connected to the Cascade Down connector of the base unit terminates in the
Cascade Up connector physically at the bottom of the stack. This next unit is designated unit
2. The stack is wired upward through the units and the system continues to number in this
manner throughout the stack. In this configuration, the base unit discovers the stack in a
60 Installation November 2010