Set this policy to specify an arbitrary group ID that the device belongs to. Use this if you need to: 1. Limit the #of devices participating in peering in a domain network with many users. 2. Create a single group for Local Network Peering for branches that are on different domains or are not on the same NAT. Note: this is a best effort optimization and should not be relied on for an authentication of identity. You must use a GUID as the group ID.