Is RSTP compatible with classic STP?

Yes, RSTP (Rapid Spanning Tree Protocol) is indeed compatible with classic STP (Spanning Tree Protocol) because RSTP was designed to be an evolution of STP, allowing for faster convergence while maintaining backward compatibility. This means that RSTP can operate in a network that includes STP devices.

For RSTP to function effectively in such mixed environments, administrators need to ensure that specific configurations are applied to the interfaces. This may involve using port roles and states that are compatible with both protocols. RSTP recognizes the legacy bridge (which runs classic STP) and can co-exist in a network by maintaining proper communication and operation between the two protocols.

In scenarios where both RSTP and STP are present, RSTP will adapt to the slower convergence times of STP devices, so configurations may require careful management to optimize network performance while ensuring stability. Such implementations enable organizations to upgrade their networks incrementally without needing to replace all existing STP devices at once.