Bonjour missing from list of services

Yesterday I updated the system software (10.12.6) and today I cannot connect using bonjour. There was a hint that bonjour has been bundled with iTunes 12.7.1 so I performed that update but it bonjour still doesn't show in the list of services. Anyone know how I can fix this? I have an iTunes app that uses bonjour.

BTW, the only discussion involving bonjour that I could find was listed under Windows. Has Apple discontinued bonjour in Sierra? or have they just abandoned supporting it?