This read-only value identifies how the units in a Paradyne stack are physically interconnected, either daisyChain(1) or star(2) topology. An admin checks this to understand the stack's cabling arrangement, which affects how failures propagate and how units should be added or removed from the stack. For example, seeing pdnStackMethod report star(2) tells the admin each unit connects independently to a central point rather than in a chained sequence, which matters when planning maintenance that avoids taking down the whole stack.