Do all switches run Spanning Tree Protocol by default?

Spanning Tree Protocol (STP) is a network protocol that ensures a loop-free topology for computer networks. By default, most switches, particularly managed switches, have STP enabled to prevent broadcast storms and to maintain a stable environment in the case of redundant paths between devices. This default behavior helps to automatically detect and block redundant paths that could create loops.

Managed switches, which are more complex and capable of advanced configurations, typically come with STP enabled. While some basic or unmanaged switches may not support STP, the question targets the general behavior of switches used in most networking environments where managed switches predominate, and thus they usually run STP by default.

Only specific types of switches, such as unmanaged switches, may not support STP at all, and certain environments might require additional configuration to fully leverage STP or other variants. Hence, the understanding that "Yes, all switches run Spanning Tree Protocol by default" applies broadly in the context of managed switch behavior in typical network setups.