Bonjour Fencing

Bonjour Fencing provides a mechanism to limit the scope of Bonjour (mDNS) service discovery in the physical/spatial domain.

While Bonjour Fencing is related to Bonjour Gateway, they are two separate features designed for different purposes. Bonjour Gateway bridges mDNS services across VLANs, and is useful because Bonjour is designed as a same-VLAN protocol. Bonjour Fencing limits the range of Bonjour service discovery within physical space, which is useful because logical network boundaries (e.g. VLANs) do not always correlate well to physical boundaries within a building/floor.

The following considerations should be taken into account before deploying Bonjour fencing policies:

  • Bonjour fencing is not supported on Mesh APs.
  • Switch interfaces to which APs are connected must be configured in VLAN trunk mode so that Bonjour traffic gets forwarded across VLANs based on Bonjour Gateway Policies.
  • Bonjour fencing is implemented at the AP, not at the controller.
  • Fencing policies can be applied on a zone level only, and cannot be configured per AP group.
  • In order for a wired fencing policy to work properly, wireless fencing for the same mDNS service should also be enabled. If wired fencing is enabled but wireless is disabled, APs that are not the "closest AP" will be unable to determine whether the source of the mDNS advertisement was wired or wireless.
Parent topic: Bonjour