Cabletron Systems bridges Manuel D’Utilisation

The Workgroup Approach

3-4

Stackables

To cope with the limited flexibility and expandability of standalones, the 
stackable hub, or stackable, was developed. The stackable design allowed a series 
of devices to act as a single device. With a stackable hub system, five separate 
devices could act as a single device. From the point of view of network design, 
this was a master stroke. A single stack, which operated as one big device, could 
support as many users as four or five standalone repeaters. To the network, the 
separate devices appeared to be a single device, as shown in Figure 3-2.

Figure 3-2. Physical and Logical Views of Stackables

The stackable has a smaller network footprint than an equivalent number of 
standalone devices. In effect, the stack fools the network into thinking that the 
users connected to the stack are in a single repeater or concentrator.

By placing stackables together in a collection called a stack, the available options 
for user connections at individual workgroup locations grew dramatically. Also, 
the ability to simply add stackables to the stack in order to accommodate new 
users gave some measure of an upgrade path to users of stackable devices.

Stackables, being less expensive than modular hubs and more flexible and 
expandable than standalones, helped to fill in the chasm between the high-end 
and low-end network strategies.

Stackable hubs of different technologies cannot be mixed. Each 
stack must use a single networking technology. For example, 
you cannot combine Ethernet and Fast Ethernet stackables in a 
single stack.

physical organization

logical organization

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