This optional attribute specifies the value of the id attribute for another Sottoprocesso Arbortext PE pool that can take overflow of processing requests. The cascade attribute allows one pool to take the overflow from another to improve servicing requests. If the Sottoprocesso Arbortext PE pool being queried determines that it can accept an HTTP request, but no Sottoprocessi Arbortext PE are available and no additional Sottoprocessi Arbortext PE can be started, the pool will pass the request to the pool identified by its cascade attribute. You can configure a series of pools to cascade from one to another, where pool A can cascade to pool B, pool B can cascade to pool C, and so on.