Your company has a branch location that uses a Juniper Networks EX Series Switch.

This scenario describes end hosts — virtualization hosts running software switches or virtual bridging stacks — unexpectedly generating and transmitting BPDUs on ports that are supposed to be pure edge (host-facing) ports where no BPDUs should ever legitimately be received. BPDU protection (BPDU guard) is the Junos feature purpose-built for exactly this situation: when applied to an edge-designated interface, it continuously monitors that port for any incoming BPDU, and the moment one is detected, it immediately and automatically disables the port, preventing the unexpected BPDU source from ever participating in or influencing the spanning-tree topology calculation, thereby protecting the stable, intended topology from disruption caused by unauthorized or accidental BPDU generation at the access edge. This directly and precisely resolves the described problem at its source, since the root cause is illegitimate BPDUs arriving on ports that were never meant to see them. Increasing the max-age timer only adjusts how long stale topology information is retained before being aged out and has no effect on preventing rogue BPDUs from being processed in the first place. Disabling RSTP outright on access interfaces would eliminate spanning tree's loop-prevention protection on those ports entirely, introducing a much more severe risk of undetected Layer 2 loops. Root protection (root guard) defends specifically against a port attempting to become the root port by receiving a superior BPDU claiming a better path to root; it addresses a different threat model than blocking any BPDU outright on a true edge port. Reference topics: Junos Enterprise Switching – Spanning Tree Protocols, BPDU Protection on Edge Interfaces.