1. A machine readable medium on which instructions are stored, comprising instructions that when executed cause a machine to: collect, by a local trusted network device, local trust data related to behavior of the local trusted network device; receive, from one or more remote trusted network devices, additional trust data for the local trusted network device; calculate a combined trust score for the local trusted network device based on the local trust data and additional trust data; and modify activity of the local trusted network device based on the combined trust score.